88 results on '"Silverman JS"'
Search Results
2. Predictors of Hydrocephalus Risk After Stereotactic Radiosurgery for Vestibular Schwannomas: Utility of the Evans Index.
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Santhumayor BA, Mashiach E, Meng Y, Rotman L, Golub D, Bernstein K, Vasconcellos FN, Silverman JS, Harter DH, Golfinos JG, and Kondziolka D
- Abstract
Background and Objectives: Hydrocephalus after Gamma Knife® stereotactic radiosurgery (SRS) for vestibular schwannomas is a rare but manageable occurrence. Most series report post-SRS communicating hydrocephalus in about 1% of patients, thought to be related to a release of proteinaceous substances into the cerebrospinal fluid. While larger tumor size and older patient age have been associated with post-SRS hydrocephalus, the influence of baseline ventricular anatomy on hydrocephalus risk remains poorly defined., Methods: A single-institution retrospective cohort study examining patients who developed symptomatic communicating hydrocephalus after undergoing Gamma Knife® SRS for unilateral vestibular schwannomas from 2011 to 2021 was performed. Patients with prior hydrocephalus and cerebrospinal fluid diversion or prior surgical resection were excluded. Baseline tumor volume, third ventricle width, and Evans Index (EI)-maximum width of the frontal horns of the lateral ventricles/maximum internal diameter of the skull-were measured on axial postcontrast T1-weighted magnetic resonance imaging., Results: A total of 378 patients met the inclusion criteria; 14 patients (3.7%) developed symptomatic communicating hydrocephalus and 10 patients (2.6%) underwent shunt placement and 4 patients (1.1%) were observed with milder symptoms. The median age of patients who developed hydrocephalus was 69 years (IQR, 67-72) and for patients younger than age 65 years, the risk was 1%. For tumor volumes <1 cm3, the risk of requiring shunting was 1.2%. The odds of developing symptomatic hydrocephalus were 5.0 and 7.7 times higher in association with a baseline EI > 0.28 (P = .024) and tumor volume >3 cm3 (P = .007), respectively, in multivariate analysis. Fourth ventricle distortion on pre-SRS imaging was significantly associated with hydrocephalus incidence (P < .001)., Conclusion: Patients with vestibular schwannoma with higher baseline EI, larger tumor volumes, and fourth ventricle deformation are at increased odds of developing post-SRS hydrocephalus. These patients should be counseled regarding risk of hydrocephalus and carefully monitored after SRS., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)
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- 2024
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3. Improved outcomes for triple negative breast cancer brain metastases patients after stereotactic radiosurgery and new systemic approaches.
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Mashiach E, Alzate JD, De Nigris Vasconcellos F, Adams S, Santhumayor B, Meng Y, Schnurman Z, Donahue BR, Bernstein K, Orillac C, Bollam R, Kwa MJ, Meyers M, Oratz R, Novik Y, Silverman JS, Harter DH, Golfinos JG, and Kondziolka D
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- Humans, Female, Middle Aged, Aged, Prospective Studies, Adult, Survival Rate, Follow-Up Studies, Prognosis, Treatment Outcome, Registries, Radiosurgery, Brain Neoplasms secondary, Brain Neoplasms mortality, Triple Negative Breast Neoplasms pathology, Triple Negative Breast Neoplasms mortality, Triple Negative Breast Neoplasms therapy
- Abstract
Purpose: Although ongoing studies are assessing the efficacy of new systemic therapies for patients with triple negative breast cancer (TNBC), the overwhelming majority have excluded patients with brain metastases (BM). Therefore, we aim to characterize systemic therapies and outcomes in a cohort of patients with TNBC and BM managed with stereotactic radiosurgery (SRS) and delineate predictors of increased survival., Methods: We used our prospective patient registry to evaluate data from 2012 to 2023. We included patients who received SRS for TNBC-BM. A competing risk analysis was conducted to assess local and distant control., Results: Forty-three patients with 262 tumors were included. The median overall survival (OS) was 16 months (95% CI 13-19 months). Predictors of increased OS after initial SRS include Breast GPA score > 1 (p < 0.001) and use of immunotherapy such as pembrolizumab (p = 0.011). The median time on immunotherapy was 8 months (IQR 4.4, 11.2). The median time to new CNS lesions after the first SRS treatment was 17 months (95% CI 12-22). The cumulative rate for development of new CNS metastases after initial SRS at 6 months, 1 year, and 2 years was 23%, 40%, and 70%, respectively. Thirty patients (70%) underwent multiple SRS treatments, with a median time of 5 months (95% CI 0.59-9.4 months) for the appearance of new CNS metastases after second SRS treatment., Conclusions: TNBC patients with BM can achieve longer survival than might have been previously anticipated with median survival now surpassing one year. The use of immunotherapy is associated with increased median OS of 23 months., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2024
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4. Evaluation of the SSTR2-targeted Radiopharmaceutical 177Lu-DOTATATE and SSTR2-specific 68Ga-DOTATATE PET as Imaging Biomarker in Patients with Intracranial Meningioma.
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Kurz SC, Zan E, Cordova C, Troxel AB, Barbaro M, Silverman JS, Snuderl M, Zagzag D, Kondziolka D, Golfinos JG, Chi AS, and Sulman EP
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- Adult, Humans, Male, Female, Middle Aged, Aged, Radiopharmaceuticals, Positron-Emission Tomography methods, Biomarkers, Positron Emission Tomography Computed Tomography, Meningioma diagnostic imaging, Meningioma radiotherapy, Meningioma drug therapy, Organometallic Compounds adverse effects, Meningeal Neoplasms diagnostic imaging, Meningeal Neoplasms radiotherapy, Meningeal Neoplasms drug therapy, Neuroendocrine Tumors pathology, Octreotide analogs & derivatives, Receptors, Somatostatin
- Abstract
Purpose: There are no effective medical therapies for patients with meningioma who progress beyond surgical and radiotherapeutic interventions. Somatostatin receptor type 2 (SSTR2) represents a promising treatment target in meningiomas. In this multicenter, single-arm phase II clinical study (NCT03971461), the SSTR2-targeting radiopharmaceutical 177Lu-DOTATATE is evaluated for its feasibility, safety, and therapeutic efficacy in these patients., Patients and Methods: Adult patients with progressive intracranial meningiomas received 177Lu-DOTATATE at a dose of 7.4 GBq (200 mCi) every eight weeks for four cycles. 68Ga-DOTATATE PET-MRI was performed before and six months after the start of the treatment. The primary endpoint was progression-free survival (PFS) at 6 months (PFS-6). Secondary endpoints were safety and tolerability, overall survival (OS) at 12 months (OS-12), median PFS, and median OS., Results: Fourteen patients (female = 11, male = 3) with progressive meningiomas (WHO 1 = 3, 2 = 10, 3 = 1) were enrolled. Median age was 63.1 (range 49.7-78) years. All patients previously underwent tumor resection and at least one course of radiation. Treatment with 177Lu-DOTATATE was well tolerated. Seven patients (50%) achieved PFS-6. Best radiographic response by modified Macdonald criteria was stable disease (SD) in all seven patients. A >25% reduction in 68Ga-DOTATATE uptake (PET) was observed in five meningiomas and two patients. In one lesion, this corresponded to >50% reduction in bidirectional tumor measurements (MRI)., Conclusions: Treatment with 177Lu-DOTATATE was well tolerated. The predefined PFS-6 threshold was met in this interim analysis, thereby allowing this multicenter clinical trial to continue enrollment. 68Ga-DOTATATE PET may be a useful imaging biomarker to assess therapeutic outcome in patients with meningioma., (©2023 American Association for Cancer Research.)
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- 2024
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5. Volumetric growth rate of incidentally found meningiomas on immunotherapy.
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Berger A, Mullen R, Bernstein K, Mashiach E, Meng Y, Silverman JS, Sulman EP, Golfinos JG, and Kondziolka D
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- Humans, Nivolumab therapeutic use, Ipilimumab, Retrospective Studies, Prospective Studies, Immunotherapy, Meningioma diagnostic imaging, Meningioma therapy, Meningioma pathology, Carcinoma, Non-Small-Cell Lung, Lung Neoplasms, Meningeal Neoplasms diagnostic imaging, Meningeal Neoplasms therapy, Meningeal Neoplasms pathology
- Abstract
Purpose: The expression of PD-L1 in high-grade meningiomas made it a potential target for immunotherapy research in refractory cases. Several prospective studies in this field are still on going. We sought to retrospectively investigate the effects of check-point inhibitors (CI) on meningiomas that had been naïve to either surgical or radiation approaches by following incidental meningiomas found during treatment with CI for various primary metastatic cancers., Methods: We used the NYU Perlmutter Cancer Center Data Hub to find patients treated by CI for various cancers, who also had serial computerized-tomography (CT) or magnetic-resonance imaging (MRI) reports of intracranial meningiomas. Meningioma volumetric measurements were compared between the beginning and end of the CI treatment period. Patients treated with chemotherapy during this period were excluded., Results: Twenty-five patients were included in our study, of which 14 (56%) were on CI for melanoma, 5 (20%) for non-small-cell lung cancer and others. CI therapies included nivolumab (n = 15, 60%), ipilimumab (n = 11, 44%) and pembrolizumab (n = 9, %36), while 9 (36%) were on ipilimumab/nivolumab combination. We did not find any significant difference between tumor volumes before and after treatment with CI (1.31 ± 0.46 vs. 1.34 ± 0.46, p=0.8, respectively). Among patients beyond 1 year of follow-up (n = 13), annual growth was 0.011 ± 0.011 cm
3 /year. Five patients showed minor volume reduction of 0.12 ± 0.10 cm3 (21 ± 6% from baseline). We did not find significant predictors of tumor volume reduction., Conclusion: Check-point inhibitors may impact the natural history of meningiomas. Additional research is needed to define potential clinical indications and treatment goals., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)- Published
- 2024
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6. Long-term Survival From Breast Cancer Brain Metastases in the Era of Modern Systemic Therapies.
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Mashiach E, Alzate JD, De Nigris Vasconcellos F, Bernstein K, Donahue BR, Schnurman Z, Gurewitz J, Rotman LE, Adams S, Meyers M, Oratz R, Novik Y, Kwa MJ, Silverman JS, Sulman EP, Golfinos JG, and Kondziolka D
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- Humans, Female, Central Nervous System, Retrospective Studies, Breast Neoplasms radiotherapy, Brain Neoplasms secondary, Radiosurgery methods
- Abstract
Background and Objectives: Median survival for all patients with breast cancer with brain metastases (BCBMs) has increased in the era of targeted therapy (TT) and with improved local control of intracranial tumors using stereotactic radiosurgery (SRS) and surgical resection. However, detailed characterization of the patients with long-term survival in the past 5 years remains sparse. The aim of this article is to characterize patients with BCBM who achieved long-term survival and identify factors associated with the uniquely better outcomes and to find predictors of mortality for patients with BCBM., Methods: We reviewed 190 patients with breast cancer with 931 brain tumors receiving SRS who were followed at our institution with prospective data collection between 2012 and 2022. We analyzed clinical, molecular, and imaging data to assess relationship to outcomes and tumor control., Results: The median overall survival from initial SRS and from breast cancer diagnosis was 25 months (95% CI 19-31 months) and 130 months (95% CI 100-160 months), respectively. Sixteen patients (17%) achieved long-term survival (survival ≥5 years from SRS), 9 of whom are still alive. Predictors of long-term survival included HER2+ status ( P = .041) and treatment with TT ( P = .046). A limited number of patients (11%) died of central nervous system (CNS) causes. A predictor of CNS-related death was the development of leptomeningeal disease after SRS ( P = .025), whereas predictors of non-CNS death included extracranial metastases at first SRS ( P = .017), triple-negative breast cancer ( P = .002), a Karnofsky Performance Status of <80 at first SRS ( P = .002), and active systemic disease at last follow-up ( P = .001). Only 13% of patients eventually needed whole brain radiotherapy. Among the long-term survivors, none died of CNS progression., Conclusion: Patients with BCBM can achieve long-term survival. The use of TT and HER2+ disease are associated with long-term survival. The primary cause of death was extracranial disease progression, and none of the patients living ≥5 years died of CNS-related disease., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)
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- 2024
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7. Low-Dose Radiosurgery for Brain Metastases in the Era of Modern Systemic Therapy.
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Alzate JD, Mashiach E, Berger A, Bernstein K, Mullen R, Nigris Vasconcellos F, Qu T, Silverman JS, Donahue BR, Cooper BT, Sulman EP, Golfinos JG, and Kondziolka D
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- Humans, Brain pathology, Retrospective Studies, Treatment Outcome, Longitudinal Studies, Brain Neoplasms pathology, Melanoma secondary, Radiosurgery adverse effects
- Abstract
Background and Objectives: Dose selection for brain metastases stereotactic radiosurgery (SRS) classically has been based on tumor diameter with a reduction of dose in the settings of prior brain irradiation, larger tumor volumes, and critical brain location. However, retrospective series have shown local control rates to be suboptimal with reduced doses. We hypothesized that lower doses could be effective for specific tumor biologies with concomitant systemic therapies. This study aims to report the local control (LC) and toxicity when using low-dose SRS in the era of modern systemic therapy., Methods: We reviewed 102 patients with 688 tumors managed between 2014 and 2021 who had low-margin dose radiosurgery, defined as ≤14 Gy. Tumor control was correlated with demographic, clinical, and dosimetric data., Results: The main primary cancer types were lung in 48 (47.1%), breast in 31 (30.4%), melanoma in 8 (7.8%), and others in 15 patients (11.7%). The median tumor volume was 0.037cc (0.002-26.31 cm 3 ), and the median margin dose was 14 Gy (range 10-14). The local failure (LF) cumulative incidence at 1 and 2 years was 6% and 12%, respectively. On competing risk regression analysis, larger volume, melanoma histology, and margin dose were predictors of LF. The 1-year and 2-year cumulative incidence of adverse radiation effects (ARE: an adverse imaging-defined response includes increased enhancement and peritumoral edema) was 0.8% and 2%., Conclusion: It is feasible to achieve acceptable LC in BMs with low-dose SRS. Volume, melanoma histology, and margin dose seem to be predictors for LF. The value of a low-dose approach may be in the management of patients with higher numbers of small or adjacent tumors with a history of whole brain radio therapy or multiple SRS sessions and in tumors in critical locations with the aim of LC and preservation of neurological function., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)
- Published
- 2023
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8. Quantitative Analysis of Parenchymal Effects and Flow of Large Arteriovenous Malformations Managed With Stereotactic Radiosurgery.
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Alzate JD, Mashiach E, Bernstein K, De Nigris Vasconcellos F, Qu T, Silverman JS, Shapiro M, Nelson PK, Raz E, Riina HA, and Kondziolka D
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- Humans, Treatment Outcome, Retrospective Studies, Brain surgery, Follow-Up Studies, Radiosurgery adverse effects, Intracranial Arteriovenous Malformations diagnostic imaging, Intracranial Arteriovenous Malformations radiotherapy, Intracranial Arteriovenous Malformations surgery
- Abstract
Background and Objectives: Stereotactic radiosurgery (SRS) of larger arteriovenous malformations (AVM) is associated with an elevated incidence of adverse radiation effects (ARE). To date, volume-response and dose-response models have been used to predict such effects. To understand radiological outcomes and their hemodynamic effects on the regional brain., Methods: A retrospective analysis was conducted at our institution using a prospective registry of patients managed between 2014 and 2020. We included patients with AVM with a nidus larger than 5 cc who received either single-session or volume-staged Gamma Knife radiosurgery. AVM volume changes, volumes of parenchymal response, and obliteration were analyzed and correlated with transit times and diameters of feeding arteries and draining veins., Results: Sixteen patients underwent single-session SRS, and 9 patients underwent volume-staged SRS. The average AVM volume was 12.6 cc (5.5-23). The AVM locations were predominantly lobar (80%) and 17 (68%) were in critical locations. The mean margin dose was 17.2 Gy (15-21), and the median V12Gy was 25.5 cc. Fourteen (56%) AVMs had a transit time shorter than 1 second. The median vein-artery ratio (sum diameter of the veins/sum diameter of feeding arteries) was 1.63 (range, 0.60-4.19). Asymptomatic parenchymal effects were detected in 13 (52%) patients and were symptomatic in 4 (16%) patients. The median time to ARE was 12 months (95% CI 7.6-16.4). On univariate analysis, significant predictors of ARE were lower vein-artery ratio ( P = .024), longer transit time ( P = .05), higher mean dose ( P = .028), and higher D95 ( P = .036)., Conclusion: Transit times and vessel diameters are valuable predictors of the subsequent parenchymal response after SRS. A more quantitative understanding of blood flow is critical for predicting the effects on the regional brain after AVM radiosurgery., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)
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- 2023
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9. EGFR-mutated non-small lung cancer brain metastases and radiosurgery outcomes with a focus on leptomeningeal disease.
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Alzate JD, Mullen R, Mashiach E, Bernstein K, De Nigris Vasconcellos F, Rotmann L, Berger A, Qu T, Silverman JS, Golfinos JG, Donahue BR, and Kondziolka D
- Abstract
Purpose: Patients with EGFR-mutated NSCLC represent a unique subset of lung cancer patients with distinct clinical and molecular characteristics. Previous studies have shown a higher incidence of brain metastases (BM) in this subgroup of patients, and neurologic death has been reported to be as high as 40% and correlates with leptomeningeal disease (LMD)., Methods: Between 2012 and 2021, a retrospective review of our prospective registry identified 606 patients with BM from NSCLC, with 170 patients having an EGFR mutation. Demographic, clinical, radiographic, and treatment characteristics were correlated to the incidence of LMD and survival., Results: LMD was identified in 22.3% of patients (n = 38) at a median follow-up of 19 (2-98) months from initial SRS. Multivariate regression analysis showed targeted therapy and a cumulative number of metastases as significant predictors of LMD (p = 0.034, HR = 0.44), (p = .04, HR = 1.02). The median survival time after SRS of the 170 patients was 24 months (CI 95% 19.1-28.1). In a multivariate Cox regression analysis, RPA, exon 19 deletion, and osimertinib treatment were significant predictors of overall survival. The cumulative incidence of neurological death at 2 and 4 years post initial stereotactic radiosurgery (SRS) was 8% and 11%, respectively, and correlated with LMD., Conclusion: The study shows that current-generation targeted therapy for EGFR-mutated NSCLC patients may prevent the development and progression of LMD, leading to improved survival outcomes. Nevertheless, LMD is associated with poor outcomes and neurologic death, making innovative strategies to treat LMD essential., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2023
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10. Extended Survival in Patients With Non-Small-Cell Lung Cancer-Associated Brain Metastases in the Modern Era.
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Berger A, Mullen R, Bernstein K, Alzate JD, Silverman JS, Sulman EP, Donahue BR, Chachoua A, Shum E, Velcheti V, Sabari J, Golfinos JG, and Kondziolka D
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- Humans, Aged, Retrospective Studies, Carcinoma, Non-Small-Cell Lung therapy, Lung Neoplasms pathology, Radiosurgery methods, Brain Neoplasms pathology
- Abstract
Background: Brain metastases (BM) have long been considered a terminal diagnosis with management mainly aimed at palliation and little hope for extended survival. Use of brain stereotactic radiosurgery (SRS) and/or resection, in addition to novel systemic therapies, has enabled improvements in overall and progression-free (PFS) survival., Objective: To explore the possibility of extended survival in patients with non-small-cell lung cancer (NSCLC) BM in the current era., Methods: During the years 2008 to 2020, 606 patients with NSCLC underwent their first Gamma Knife SRS for BM at our institution with point-of-care data collection. We reviewed clinical, molecular, imaging, and treatment parameters to explore the relationship of such factors with survival., Results: The median overall survival was 17 months (95% CI, 13-40). Predictors of increased survival in a multivariable analysis included age <65 years ( P < .001), KPS ≥80 ( P < .001), absence of extracranial metastases ( P < .001), fewer BM at first SRS (≤3, P = .003), and targeted therapy ( P = .005), whereas chemotherapy alone was associated with shorter survival ( P = .04). In a subgroup of patients managed before 2016 (n = 264), 38 (14%) were long-term survivors (≥5 years), of which 16% required no active cancer treatment (systemic or brain) for ≥3 years by the end of their follow-up., Conclusion: Long-term survival in patients with brain metastases from NSCLC is feasible in the current era of SRS when combined with the use of effective targeted therapeutics. Of those living ≥5 years, the chance for living with stable disease without the need for active treatment for ≥3 years was 16%., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)
- Published
- 2023
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11. How many brain metastases can be treated with stereotactic radiosurgery before the radiation dose delivered to normal brain tissue rivals that associated with standard whole brain radiotherapy?
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Becker SJ, Lipson EJ, Jozsef G, Molitoris JK, Silverman JS, Presser J, and Kondziolka D
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- Humans, Brain, Cranial Irradiation methods, Quality of Life, Radiation Dosage, Retrospective Studies, Brain Neoplasms radiotherapy, Brain Neoplasms surgery, Brain Neoplasms secondary, Radiosurgery methods
- Abstract
Introduction: Clinical trial data comparing outcomes after administration of stereotactic radiosurgery (SRS) or whole-brain radiotherapy (WBRT) to patients with brain metastases (BM) suggest that SRS better preserves cognitive function and quality of life without negatively impacting overall survival. Here, we estimate the maximum number of BM that can be treated using single and multi-session SRS while limiting the dose of radiation delivered to normal brain tissue to that associated with WBRT., Methods: Multiple-tumor SRS was simulated using a Monte Carlo - type approach and a pre-calculated dose kernel method. Tumors with diameters ≤36 mm were randomly placed throughout the contoured brain parenchyma until the brain mean dose reached 3 Gy, equivalent to the radiation dose delivered during a single fraction of a standard course of WBRT (a total dose of 30 Gy in 10 daily fractions of 3 Gy). Distribution of tumor sizes, dose coverage, selectivity, normalization, and maximum dose data used in the simulations were based on institutional clinical metastases data., Results: The mean number of tumors treated, mean volume of healthy brain tissue receiving > 12 Gy (V12) per tumor, and total tumor volume treated using mixed tumor size distributions were 12.7 ± 4.2, 2.2 cc, and 12.9 cc, respectively. Thus, we estimate that treating 12-13 tumors per day over 10 days would deliver the dose of radiation to healthy brain tissue typically associated with a standard course of WBRT., Conclusion: Although in clinical practice, treatment with SRS is often limited to patients with ≤15 BM, our findings suggest that many more lesions could be targeted while still minimizing the negative impacts on quality of life and neurocognition often associated with WBRT. Results from this in silico analysis require clinical validation., (© 2022 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)
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- 2023
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12. Readmission with acute kidney injury following ileostomy: patterns and predictors of a common phenomenon.
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Pencovich N, Silverman JS, Horesh N, Nevo N, Eshkenazy R, Kent I, Ram E, and Nachmany I
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- Humans, Ileostomy adverse effects, Kidney, Albumins, Patient Readmission, Acute Kidney Injury epidemiology, Acute Kidney Injury etiology
- Abstract
Purpose: Ileostomy is associated with various complications, often necessitating rehospitalization. High-output ileostomy is common and may lead to acute kidney injury (AKI). Here we describe the temporal pattern of readmission with AKI following ileostomy formation and identify risk factors., Methods: Patients that underwent formation of ileostomy between 2008 and 2021 were included in this study. Readmission with AKI with high output ileostomy was defined as readmission with serum creatinine > 1.5-fold compared to the level at discharge or latest baseline (at least stage-1 AKI according to Kidney Disease: Improving Global Outcome (KDIGO) criteria), accompanied by ileostomy output > 1000 ml in 24 h. Patient characteristics and perioperative course were assessed to identify predictors for readmission with AKI., Results: Of 1191 patients who underwent ileostomy, 198 (16.6%) were readmitted with a high output stoma and AKI. The mean time to readmission with AKI was 98.97 ± 156.36 days. Eighty-six patients (43.4%) had early readmission (within 30 days), and 66 (33%) were readmitted after more than 90 days. Over 90% of patients had more than one readmission, and 110 patients (55%) had 5 or more. Patient-related predictors for readmission with AKI were age > 65, body mass index > 30 kg/m
2 , and hypertension. Factors related to the postoperative course were AKI with creatinine > 2 mg/dl, postoperative hemoglobin < 8 g/dl or blood transfusion, albumin < 20 g/dl, high output stoma and need for loperamide, and length of hospital stay > 20 days. Factors related to early versus late readmissions and multiple readmissions were also analyzed., Conclusions: Readmission with AKI following ileostomy formation is a consequential event with distinct risk factors. Acknowledging these risk factors is the foundation for designing interventions aiming to reduce frequency of AKI readmissions in predisposed patient populations., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2023
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13. Modern Hearing Preservation Outcomes After Vestibular Schwannoma Stereotactic Radiosurgery.
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Berger A, Alzate JD, Bernstein K, Mullen R, McMenomey S, Jethanemest D, Friedmann DR, Smouha E, Sulman EP, Silverman JS, Roland JT, Golfinos JG, and Kondziolka D
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- Follow-Up Studies, Hearing, Hearing Tests, Humans, Middle Aged, Retrospective Studies, Treatment Outcome, Hearing Loss etiology, Hearing Loss prevention & control, Hearing Loss surgery, Neuroma, Acoustic complications, Neuroma, Acoustic radiotherapy, Neuroma, Acoustic surgery, Radiosurgery adverse effects
- Abstract
Background: For patients with vestibular schwannoma (VS), stereotactic radiosurgery (SRS) has proven effective in controlling tumor growth while hearing preservation remains a key goal., Objective: To evaluate hearing outcomes in the modern era of cochlear dose restriction., Methods: During the years 2013 to 2018, 353 patients underwent Gamma knife surgery for VS at our institution. We followed 175 patients with pre-SRS serviceable hearing (Gardner-Robertson Score, GR 1 and 2). Volumetric and dosimetry data were collected, including biological effective dose, integral doses of total and intracanalicular tumor components, and hearing outcomes., Results: The mean age was 56 years, 74 patients (42%) had a baseline GR of 2, and the mean cochlear dose was 3.5 Gy. The time to serviceable hearing loss (GR 3-4) was 38 months (95% CI 26-46), with 77% and 62% hearing preservation in the first and second years, respectively. Patients optimal for best hearing outcomes were younger than 58 years with a baseline GR of 1, free canal space ≥0.041 cc (diameter of 4.5 mm), and mean cochlear dose <3.1 Gy. For such patients, hearing preservation rates were 92% by 12 months and 81% by 2 years, staying stable for >5 years post-SRS, significantly higher than the rest of the population., Conclusion: Hearing preservation after SRS for patients with VS with serviceable hearing is correlated to the specific baseline GR score (1 or 2), age, cochlear dose, and biological effective dose. Increased tumor-free canal space correlates with better outcomes. The most durable hearing preservation correlates with factors commonly associated with smaller tumors away from the cochlea., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)
- Published
- 2022
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14. Preoperative flow analysis of arteriovenous malformations and obliteration response after stereotactic radiosurgery.
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Alzate JD, Berger A, Bernstein K, Mullen R, Qu T, Silverman JS, Shapiro M, Nelson PK, Raz E, Jafar JJ, Riina HA, and Kondziolka D
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- Humans, Treatment Outcome, Follow-Up Studies, Retrospective Studies, Radiosurgery adverse effects, Radiosurgery methods, Intracranial Arteriovenous Malformations diagnostic imaging, Intracranial Arteriovenous Malformations radiotherapy, Intracranial Arteriovenous Malformations surgery
- Abstract
Objective: Morphological and angioarchitectural features of cerebral arteriovenous malformations (AVMs) have been widely described and associated with outcomes; however, few studies have conducted a quantitative analysis of AVM flow. The authors examined brain AVM flow and transit time on angiograms using direct visual analysis and a computer-based method and correlated these factors with the obliteration response after Gamma Knife radiosurgery., Methods: A retrospective analysis was conducted at a single institution using a prospective registry of patients managed from January 2013 to December 2019: 71 patients were analyzed using a visual method of flow determination and 38 were analyzed using a computer-based method. After comparison and validation of the two methods, obliteration response was correlated to flow analysis, demographic, angioarchitectural, and dosimetric data., Results: The mean AVM volume was 3.84 cm3 (range 0.64-19.8 cm3), 32 AVMs (45%) were in critical functional locations, and the mean margin radiosurgical dose was 18.8 Gy (range 16-22 Gy). Twenty-seven AVMs (38%) were classified as high flow, 37 (52%) as moderate flow, and 7 (10%) as low flow. Complete obliteration was achieved in 44 patients (62%) at the time of the study; the mean time to obliteration was 28 months for low-flow, 34 months for moderate-flow, and 47 months for high-flow AVMs. Univariate and multivariate analyses of factors predicting obliteration included AVM nidus volume, age, and flow. Adverse radiation effects were identified in 5 patients (7%), and 67 patients (94%) remained free of any functional deterioration during follow-up., Conclusions: AVM flow analysis and categorization in terms of transit time are useful predictors of the probability of and the time to obliteration. The authors believe that a more quantitative understanding of flow can help to guide stereotactic radiosurgery treatment and set accurate outcome expectations.
- Published
- 2022
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15. Significant survival improvements for patients with melanoma brain metastases: can we reach cure in the current era?
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Berger A, Bernstein K, Alzate JD, Mullen R, Silverman JS, Sulman EP, Donahue BR, Pavlick AC, Gurewitz J, Mureb M, Mehnert J, Madden K, Palermo A, Weber JS, Golfinos JG, and Kondziolka D
- Subjects
- Aged, Female, Humans, Immunotherapy, Male, Middle Aged, Molecular Targeted Therapy, Retrospective Studies, Brain Neoplasms pathology, Melanoma pathology, Radiosurgery methods
- Abstract
Purpose: New therapies for melanoma have been associated with increasing survival expectations, as opposed to the dismal outcomes of only a decade ago. Using a prospective registry, we aimed to define current survival goals for melanoma patients with brain metastases (BM), based on state-of-the-art multimodality care., Methods: We reviewed 171 melanoma patients with BM receiving stereotactic radiosurgery (SRS) who were followed with point-of-care data collection between 2012 and 2020. Clinical, molecular and imaging data were collected, including systemic treatment and radiosurgical parameters., Results: Mean age was 63 ± 15 years, 39% were female and 29% had BRAF-mutated tumors. Median overall survival after radiosurgery was 15.7 months (95% Confidence Interval 11.4-27.7) and 25 months in patients managed since 2015. Thirty-two patients survived [Formula: see text] 5 years from their initial SRS. BRAF mutation-targeted therapies showed a survival advantage in comparison to chemotherapy (p = 0.009), but not to immunotherapy (p = 0.09). In a multivariable analysis, both immunotherapy and the number of metastases at 1
st SRS were predictors of long-term survival ([Formula: see text] 5 years) from initial SRS (p = 0.023 and p = 0.018, respectively). Five patients (16%) of the long-term survivors required no active treatment for [Formula: see text] 5 years., Conclusion: Long-term survival in patients with melanoma BM is achievable in the current era of SRS combined with immunotherapies. For those alive [Formula: see text] 5 years after first SRS, 16% had been also off systemic or local brain therapy for over 5 years. Given late recurrences of melanoma, caution is warranted, however prolonged survival off active treatment in a subset of our patients raises the potential for cure., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)- Published
- 2022
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16. Just Because You Can Does Not Mean That You Should….
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Silverman JS
- Published
- 2022
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17. Stereotactic body radiation therapy for an unresectable FGF23-secreting tumor of the cervical spine: A case report and literature review.
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Hockemeyer K, Purswani JM, Kim JK, Givi B, Zan E, Pacione D, Shapiro M, Laufer I, Feffer JB, and Silverman JS
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We present the case of a 65-year-old male with tumor-induced osteomalacia (TIO) caused by an FGF23-secreting phosphaturic tumor of C2 treated definitively with stereotactic body radiation therapy (SBRT) and kyphoplasty. The patient exhibited notable reduction in FGF23 6 weeks following radiotherapy. He also received a dose of the FGF23 monoclonal antibody, burosumab. We discuss the case with emphasis on radiation in the management of TIO. This case demonstrates SBRT as a well-tolerated local treatment option for the management of unresectable FGF23-producing tumors., Competing Interests: Authors’ disclosure of potential conflicts of interest Ilya Laufer receives royalties from Globus and SpineWave, and has received travel support from the AO Foundation. The other authors have nothing to disclose., (© 2023 Old City Publishing, Inc.)
- Published
- 2022
18. The incidence and predictors of new brain metastases in patients with non-small cell lung cancer following discontinuation of systemic therapy.
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London D, Patel DN, Donahue B, Navarro RE, Gurewitz J, Silverman JS, Sulman E, Bernstein K, Palermo A, Golfinos JG, Sabari JK, Shum E, Velcheti V, Chachoua A, and Kondziolka D
- Abstract
Objective: Patients with non-small cell lung cancer (NSCLC) metastatic to the brain are living longer. The risk of new brain metastases when these patients stop systemic therapy is unknown. The authors hypothesized that the risk of new brain metastases remains constant for as long as patients are off systemic therapy., Methods: A prospectively collected registry of patients undergoing radiosurgery for brain metastases was analyzed. Of 606 patients with NSCLC, 63 met the inclusion criteria of discontinuing systemic therapy for at least 90 days and undergoing active surveillance. The risk factors for the development of new tumors were determined using Cox proportional hazards and recurrent events models., Results: The median duration to new brain metastases off systemic therapy was 16.0 months. The probability of developing an additional new tumor at 6, 12, and 18 months was 26%, 40%, and 53%, respectively. There were no additional new tumors 22 months after stopping therapy. Patients who discontinued therapy due to intolerance or progression of the disease and those with mutations in RAS or receptor tyrosine kinase (RTK) pathways (e.g., KRAS, EGFR) were more likely to develop new tumors (hazard ratio [HR] 2.25, 95% confidence interval [CI] 1.33-3.81, p = 2.5 × 10-3; HR 2.51, 95% CI 1.45-4.34, p = 9.8 × 10-4, respectively)., Conclusions: The rate of new brain metastases from NSCLC in patients off systemic therapy decreases over time and is uncommon 2 years after cessation of cancer therapy. Patients who stop therapy due to toxicity or who have RAS or RTK pathway mutations have a higher rate of new metastases and should be followed more closely.
- Published
- 2021
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19. Predicting local failure of brain metastases after stereotactic radiosurgery with radiomics on planning MR images and dose maps.
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Wang H, Xue J, Qu T, Bernstein K, Chen T, Barbee D, Silverman JS, and Kondziolka D
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- Humans, Magnetic Resonance Imaging, ROC Curve, Retrospective Studies, Brain Neoplasms diagnostic imaging, Brain Neoplasms radiotherapy, Brain Neoplasms surgery, Radiosurgery
- Abstract
Purpose: Stereotactic radiosurgery (SRS) has become an important modality in the treatment of brain metastases. The purpose of this study is to investigate the potential of radiomic features from planning magnetic resonance (MR) images and dose maps to predict local failure after SRS for brain metastases., Materials/methods: Twenty-eight patients who received Gamma Knife (GK) radiosurgery for brain metastases were retrospectively reviewed in this IRB-approved study. 179 irradiated tumors included 42 that locally failed within one-year follow-up. Using SRS tumor volumes, radiomic features were calculated on T1-weighted contrast-enhanced MR images acquired for treatment planning and planned dose maps. 125 radiomic features regarding tumor shape, dose distribution, MR intensities and textures were extracted for each tumor. Logistic regression with automatic feature selection was built to predict tumor progression from local control after SRS. Feature selection and model evaluation using receiver operating characteristic (ROC) curves were performed in a nested cross validation (CV) scheme. The associations between selected radiomic features and treatment outcomes were statistically assessed by univariate analysis., Results: The logistic model with feature selection achieved ROC AUC of 0.82 ± 0.09 on 5-fold CV, providing 83% sensitivity and 70% specificity for predicting local failure. A total of 10 radiomic features including 1 shape feature, 6 MR images and 3 dose distribution features were selected. These features were significantly associated with treatment outcomes (p < 0.05). The model was validated on independent holdout data with an AUC of 0.78., Conclusions: Radiomic features from planning MR images and dose maps provided prognostic information in SRS for brain metastases. A model built on the radiomic features shows promise for early prediction of tumor local failure after treatment, potentially aiding in personalized care for brain metastases., (© 2021 American Association of Physicists in Medicine.)
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- 2021
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20. Hippocampal sparing in patients receiving radiosurgery for ≥25 brain metastases.
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Kavi A, Gurewitz J, Benjamin CG, Silverman JS, Bernstein K, Mureb M, Oh C, Sulman EP, Donahue B, and Kondziolka D
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- Hippocampus, Humans, Radiotherapy Dosage, Retrospective Studies, Brain Neoplasms radiotherapy, Brain Neoplasms surgery, Radiosurgery
- Abstract
Purpose/objectives: To report our dosimetric analysis of the hippocampi (HC) and the incidence of perihippocampal tumor location in patients with ≥25 brain metastases who received stereotactic radiosurgery (SRS) in single or multiple sessions., Materials/methods: Analysis of our prospective registry identified 89 patients treated with SRS for ≥25 brain metastases. HC avoidance regions (HA-region) were created on treatment planning MRIs by 5 mm expansion of HC. Doses from each session were summed to calculate HC dose. The distribution of metastases relative to the HA-region and the HC was analyzed., Results: Median number of tumors irradiated per patient was 33 (range 25-116) in a median of 3 (range1-12) sessions. Median bilateral HC D
min (D100 ), D40 , D50 , Dmax , and Dmean (Gy) was 1.88, 3.94, 3.62, 16.6, and 3.97 for all patients, and 1.43, 2.99, 2.88, 5.64, and 3.07 for patients with tumors outside the HA-region. Multivariate linear regression showed that the median HC D40 , D50 , and Dmin were significantly correlated with the tumor number and tumor volume (p < 0.001). Of the total 3059 treated tumors, 83 (2.7%) were located in the HA-region in 57% evaluable patients; 38 tumors (1.2%) abutted or involved the HC itself., Conclusions: Hippocampal dose is higher in patients with tumors in the HA-region; however, even for patients with a high burden of intracranial disease and tumors located in the HA-regions, SRS affords hippocampal sparing. This is particularly relevant in light of our finding of eventual perihippocampal metastases in more than half of our patients., Competing Interests: Conflict of Interest Statement Dr. Kavi has nothing to disclose. Dr. Gurewitz has nothing to disclose. Dr. Benjamin has nothing to disclose. Dr. Silverman has nothing to disclose. Mr. Bernstein has nothing to disclose. Dr. Mureb has nothing to disclose. Dr. Oh has nothing to disclose. Dr. Sulman reports grants, personal fees and non-financial support from Novocure, personal fees and non-financial support from BrainLab, personal fees and non-financial support from Physician's Education Resource, personal fees and non-financial support from Merck, personal fees and non-financial support from Zai Lab, outside the submitted work. Dr. Donahue has nothing to disclose. Dr. Kondziolka reports grants from Brainlab AB, outside the submitted work., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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21. Full automation of spinal stereotactic radiosurgery and stereotactic body radiation therapy treatment planning using Varian Eclipse scripting.
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Teruel JR, Malin M, Liu EK, McCarthy A, Hu K, Cooper BT, Sulman EP, Silverman JS, and Barbee D
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- Automation, Humans, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted, Retrospective Studies, Radiosurgery
- Abstract
The purpose of this feasibility study is to develop a fully automated procedure capable of generating treatment plans with multiple fractionation schemes to improve speed, robustness, and standardization of plan quality. A fully automated script was implemented for spinal stereotactic radiosurgery/stereotactic body radiation therapy (SRS/SBRT) plan generation using Eclipse v15.6 API. The script interface allows multiple dose/fractionation plan requests, planning target volume (PTV) expansions, as well as information regarding distance/overlap between spinal cord and targets to drive decision-making. For each requested plan, the script creates the course, plans, field arrangements, and automatically optimizes and calculates dose. The script was retrospectively applied to ten computed tomography (CT) scans of previous cervical, thoracic, and lumbar spine SBRT patients. Three plans were generated for each patient - simultaneous integrated boost (SIB) 1800/1600 cGy to gross tumor volume (GTV)/PTV in one fraction; SIB 2700/2100 cGy to GTV/PTV in three fractions; and 3000 cGy to PTV in five fractions. Plan complexity and deliverability patient-specific quality assurance (QA) was performed using ArcCHECK with an Exradin A16 chamber inserted. Dose objectives were met for all organs at risk (OARs) for each treatment plan. Median target coverage was GTV V100% = 87.3%, clinical target volume (CTV) V100% = 95.7% and PTV V100% = 88.0% for single fraction plans; GTV V100% = 95.6, CTV V100% = 99.6% and PTV V100% = 97.2% for three fraction plans; and GTV V100% = 99.6%, CTV V100% = 99.1% and PTV V100% = 97.2% for five fraction plans. All plans (n = 30) passed patient-specific QA (>90%) at 2%/2 mm global gamma. A16 chamber dose measured at isocenter agreed with planned dose within 3% for all cases. Automatic planning for spine SRS/SBRT through scripting increases efficiency, standardizes plan quality and approach, and provides a tool for target coverage comparison of different fractionation schemes without the need for additional resources., (© 2020 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.)
- Published
- 2020
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22. Evaluation of First-line Radiosurgery vs Whole-Brain Radiotherapy for Small Cell Lung Cancer Brain Metastases: The FIRE-SCLC Cohort Study.
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Rusthoven CG, Yamamoto M, Bernhardt D, Smith DE, Gao D, Serizawa T, Yomo S, Aiyama H, Higuchi Y, Shuto T, Akabane A, Sato Y, Niranjan A, Faramand AM, Lunsford LD, McInerney J, Tuanquin LC, Zacharia BE, Chiang V, Singh C, Yu JB, Braunstein S, Mathieu D, Touchette CJ, Lee CC, Yang HC, Aizer AA, Cagney DN, Chan MD, Kondziolka D, Bernstein K, Silverman JS, Grills IS, Siddiqui ZA, Yuan JC, Sheehan JP, Cordeiro D, Nosaki K, Seto T, Deibert CP, Verma V, Day S, Halasz LM, Warnick RE, Trifiletti DM, Palmer JD, Attia A, Li B, Cifarelli CP, Brown PD, Vargo JA, Combs SE, Kessel KA, Rieken S, Patel S, Guckenberger M, Andratschke N, Kavanagh BD, and Robin TP
- Subjects
- Aged, Brain Neoplasms secondary, Female, Humans, Lung Neoplasms pathology, Male, Middle Aged, Retrospective Studies, Small Cell Lung Carcinoma pathology, Brain Neoplasms radiotherapy, Cranial Irradiation, Lung Neoplasms radiotherapy, Radiosurgery, Small Cell Lung Carcinoma radiotherapy
- Abstract
Importance: Although stereotactic radiosurgery (SRS) is preferred for limited brain metastases from most histologies, whole-brain radiotherapy (WBRT) has remained the standard of care for patients with small cell lung cancer. Data on SRS are limited., Objective: To characterize and compare first-line SRS outcomes (without prior WBRT or prophylactic cranial irradiation) with those of first-line WBRT., Design, Setting, and Participants: FIRE-SCLC (First-line Radiosurgery for Small-Cell Lung Cancer) was a multicenter cohort study that analyzed SRS outcomes from 28 centers and a single-arm trial and compared these data with outcomes from a first-line WBRT cohort. Data were collected from October 26, 2017, to August 15, 2019, and analyzed from August 16, 2019, to November 6, 2019., Interventions: SRS and WBRT for small cell lung cancer brain metastases., Main Outcomes and Measures: Overall survival, time to central nervous system progression (TTCP), and central nervous system (CNS) progression-free survival (PFS) after SRS were evaluated and compared with WBRT outcomes, with adjustment for performance status, number of brain metastases, synchronicity, age, sex, and treatment year in multivariable and propensity score-matched analyses., Results: In total, 710 patients (median [interquartile range] age, 68.5 [62-74] years; 531 men [74.8%]) who received SRS between 1994 and 2018 were analyzed. The median overall survival was 8.5 months, the median TTCP was 8.1 months, and the median CNS PFS was 5.0 months. When stratified by the number of brain metastases treated, the median overall survival was 11.0 months (95% CI, 8.9-13.4) for 1 lesion, 8.7 months (95% CI, 7.7-10.4) for 2 to 4 lesions, 8.0 months (95% CI, 6.4-9.6) for 5 to 10 lesions, and 5.5 months (95% CI, 4.3-7.6) for 11 or more lesions. Competing risk estimates were 7.0% (95% CI, 4.9%-9.2%) for local failures at 12 months and 41.6% (95% CI, 37.6%-45.7%) for distant CNS failures at 12 months. Leptomeningeal progression (46 of 425 patients [10.8%] with available data) and neurological mortality (80 of 647 patients [12.4%] with available data) were uncommon. On propensity score-matched analyses comparing SRS with WBRT, WBRT was associated with improved TTCP (hazard ratio, 0.38; 95% CI, 0.26-0.55; P < .001), without an improvement in overall survival (median, 6.5 months [95% CI, 5.5-8.0] for SRS vs 5.2 months [95% CI, 4.4-6.7] for WBRT; P = .003) or CNS PFS (median, 4.0 months for SRS vs 3.8 months for WBRT; P = .79). Multivariable analyses comparing SRS and WBRT, including subset analyses controlling for extracranial metastases and extracranial disease control status, demonstrated similar results., Conclusions and Relevance: Results of this study suggest that the primary trade-offs associated with SRS without WBRT, including a shorter TTCP without a decrease in overall survival, are similar to those observed in settings in which SRS is already established.
- Published
- 2020
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23. Stereotactic Radiation for Treating Primary and Metastatic Neoplasms of the Spinal Cord.
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Liu EK, Silverman JS, and Sulman EP
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Stereotactic radiation treatment can be used to treat spinal cord neoplasms in patients with either unresectable lesions or residual disease after surgical resection. While treatment guidelines have been suggested for epidural lesions, the utility of stereotactic radiation for intradural and intramedullary malignancies is still debated. Prior reports have suggested that stereotactic radiation approaches can be used for effective tumor control and symptom management. Treatment-related toxicity has been documented in rare subsets of patients, though the incidences of injury are not directly correlated with higher radiation doses. Further studies are needed to assess the factors that influence the risk of radiation-induced myelopathy when treating spinal cord neoplasms with stereotactic radiation, which can include, but may not be limited to, maximum dose, dose-fractionation, irradiated volume, tumor location, histology and treatment history. This review will discuss evidence for current treatment approaches., (Copyright © 2020 Liu, Silverman and Sulman.)
- Published
- 2020
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24. Letters.
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Silverman JS
- Subjects
- Forensic Psychiatry
- Published
- 2018
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25. The relationship of dose to nerve volume in predicting pain recurrence after stereotactic radiosurgery in trigeminal neuralgia.
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Wolf A, Tyburczy A, Ye JC, Fatterpekar G, Silverman JS, and Kondziolka D
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- Adult, Aged, Aged, 80 and over, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Prospective Studies, Radiosurgery, Recurrence, Treatment Outcome, Trigeminal Nerve diagnostic imaging, Trigeminal Neuralgia diagnostic imaging, Trigeminal Neuralgia radiotherapy
- Abstract
OBJECTIVE Approximately 75%-92% of patients with trigeminal neuralgia (TN) achieve pain relief after Gamma Knife surgery (GKS), although a proportion of these patients will experience recurrence of their pain. To evaluate the reasons for durability or recurrence, this study determined the impact of trigeminal nerve length and volume, the nerve dose-volume relationship, and the presence of neurovascular compression (NVC) on pain outcomes after GKS for TN. METHODS Fifty-eight patients with 60 symptomatic nerves underwent GKS for TN between 2013 and 2015, including 15 symptomatic nerves secondary to multiple sclerosis (MS). High-resolution MRI was acquired the day of GKS. The median maximum dose was 80 Gy for initial GKS and 65 Gy for repeat GKS. NVC, length and volume of the trigeminal nerve within the subarachnoid space of the posterior fossa, and the ratio of dose to nerve volume were assessed as predictors of recurrence. RESULTS Follow-up was available on 55 patients. Forty-nine patients (89.1%) reported pain relief (Barrow Neurological Institute [BNI] Grades I-IIIb) after GKS at a median duration of 1.9 months. The probability of maintaining pain relief (BNI Grades I-IIIb) without requiring resumption or an increase in medication was 93% at 1 year and 84% at 2 years for patients without MS, and 68% at 1 year and 51% at 2 years for all patients. The nerve length, nerve volume, target distance from the brainstem, and presence of NVC were not predictive of pain recurrence. Patients with a smaller volume of nerve (< 35% of the total nerve volume) that received a high dose (≥ 80% isodose) were less likely to experience recurrence of their TN pain after 1 year (mean time to recurrence: < 35%, 32.2 ± 4.0 months; > 35%, 17.9 ± 2.8 months, log-rank test, χ
2 = 4.3, p = 0.039). CONCLUSIONS The ratio of dose to nerve volume may predict recurrence of TN pain after GKS. Prospective studies are needed to determine the optimal dose to nerve volume ratio and whether this will result in longer pain-free outcomes.- Published
- 2018
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26. Osimertinib Dose Escalation Induces Regression of Progressive EGFR T790M-Mutant Leptomeningeal Lung Adenocarcinoma.
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Cordova C, Chi AS, Chachoua A, Kondziolka D, Silverman JS, Shepherd TM, Jain R, and Snuderl M
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- Acrylamides, Adenocarcinoma pathology, Adenocarcinoma of Lung, Aged, Aniline Compounds, Female, Humans, Lung Neoplasms pathology, Piperazines pharmacology, Protein Kinase Inhibitors pharmacology, Adenocarcinoma drug therapy, ErbB Receptors metabolism, Lung Neoplasms drug therapy, Piperazines therapeutic use, Protein Kinase Inhibitors therapeutic use
- Published
- 2017
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27. Stereotactic radiosurgery for focal leptomeningeal disease in patients with brain metastases.
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Wolf A, Donahue B, Silverman JS, Chachoua A, Lee JK, and Kondziolka D
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- Adult, Aged, Brain Neoplasms diagnostic imaging, Brain Neoplasms secondary, Cranial Irradiation, Female, Follow-Up Studies, Humans, Kaplan-Meier Estimate, Magnetic Resonance Imaging, Male, Meningeal Neoplasms diagnostic imaging, Meninges diagnostic imaging, Middle Aged, Retrospective Studies, Brain Neoplasms complications, Meningeal Neoplasms etiology, Meningeal Neoplasms surgery, Meninges surgery, Radiosurgery methods
- Abstract
Leptomeningeal disease (LMD) is well described in patients with brain metastases, presenting symptomatically in approximately 5% of patients. Conventionally, the presence of LMD is an indication for whole brain radiation therapy (WBRT) and not suitable for stereotactic radiosurgery (SRS). The purpose of the study was to evaluate the local control and overall survival of patients who underwent SRS to focal LMD. We reviewed our prospective registry and identified 32 brain metastases patients with LMD, from a total of 465 patients who underwent SRS between 2013 and 2015. Focal LMD was targeted with SRS in 16 patients. The median imaging follow-up time was 7 months. The median volume of LMD was 372 mm
3 and the median margin dose was 16 Gy. Five patients underwent prior WBRT. Histology included non-small cell lung (8), breast (5), melanoma (1), gastrointestinal (1) and ovarian cancer (1). Follow-up MR imaging was available for 14 patients. LMD was stable in 5 and partially regressed in 8 patients at follow-up. One patient had progression of LMD with hemorrhage 5 months after SRS. Seven patients developed distant LMD at a median time of 7 months. The median actuarial overall survival from SRS for LMD was 10.0 months. The 6-month and 1-year actuarial overall survival was 60% and 26% respectively. Six patients underwent WBRT after SRS for focal LMD at a median time of 6 months. Overall, focal LMD may be may be treated successfully with radiosurgery, potentially delaying WBRT in some patients.- Published
- 2017
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28. Relapsed or refractory primary central nervous system lymphoma radiosurgery: Report of the International Gamma Knife Research Foundation.
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Shin SM, Silverman JS, Bowden G, Mathieu D, Yang HC, Lee CC, Tam M, Szelemej P, Kaufmann AM, Cohen-Inbar O, Sheehan J, Niranjan A, Lunsford LD, and Kondziolka D
- Abstract
Stereotactic radiosurgery (SRS) can be used as part of multimodality management for patients with primary central nervous system lymphoma (PCNSL). The objective of this study is to evaluate outcomes of SRS for this disease. The International Gamma Knife Research Foundation identified 23 PCNSL patients who underwent SRS for either relapsed (intracerebral in-field or out-of-field tumor recurrences) or refractory disease from 1995-2014. All 23 patients presented with RPA Class I or II PCNSL, and were initially treated with a median of 7 cycles of methotrexate-based chemotherapy regimens (range, 3-26 cycles). Ten received prior whole brain radiation (WBRT) to a median dose of 43 Gy (range, 24-55 Gy). Sixteen presented with relapsed PCNSL, and seven presented with refractory disease. Twenty-three received 26 procedures of SRS. The median tumor volume was 4 cm
3 (range, 0.1-26 cm3 ), and the median margin dose was 15 Gy (range, 8-20 Gy). Median follow-up from SRS was 11 months (interquartile range, 5.7-33.2 months). Twenty presented with treatment response to twenty-three tumors (12 complete, 11 partial). Fourteen patients relapsed or were refractory to salvage SRS, and local control was 95%, 91%, and 75% at 3, 6, and 12 months post SRS. Intracranial (in-field and out-of-field) and distant (systemic) PFS was 86%, 81%, and 55% at 3, 6, and 12 months post SRS. Toxicity of SRS was low, with one developing an adverse radiation effect requiring no additional intervention. Although methotrexate-based chemotherapy regimens with or without WBRT is the first-line management option for PCNSL, SRS may be used as an alternative option in properly selected patients with smaller relapsed or refractory PCNSL tumors., Competing Interests: Authors’ disclosure of potential conflicts of interest Dr. Shin reports grants from Feinberg Lymphoma, during the conduct of the study; Dr. Lunsford is a consultant and stockholder for AB Elekta. All other authors reported no conflict of interest.- Published
- 2017
29. INTRAVITREAL BEVACIZUMAB IN THE MANAGEMENT OF BREAST CANCER IRIS METASTASIS.
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Seidman CJ, Finger PT, Silverman JS, and Oratz R
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- Fatal Outcome, Female, Humans, Intravitreal Injections, Middle Aged, Treatment Outcome, Angiogenesis Inhibitors administration & dosage, Bevacizumab administration & dosage, Breast Neoplasms pathology, Glaucoma, Angle-Closure drug therapy, Iris Neoplasms drug therapy, Iris Neoplasms secondary, Neovascularization, Pathologic drug therapy
- Abstract
Purpose: To report a case of neovascular and angle closure glaucoma secondary to breast cancer metastatic to the iris that was successfully treated with injections of intravitreal bevacizumab (Avastin) 1.25 mg/0.05 mL., Methods: Case report., Patients: A 47-year-old woman with metastatic breast cancer presented to The New York Eye Cancer Center with left ocular pain, photosensitivity, vision loss, and multiple iris nodules. Her intraocular pressure was uncontrolled. Gonioscopy revealed neovascularization of the iris and angle; no choroidal neovascularization was noted. Ultrasound biomicroscopy demonstrated tumor invasion of iris stroma with marked anterior uveal thickening and narrowed angles., Results: Three monthly injections of intravitreal bevacizumab resulted in nearly complete resolution of iris neovascularization, reduction of intraocular pressure, and control of tumor (although a small amount of residual tumor remained)., Conclusion: Intravitreal anti-vascular endothelial growth factor therapy for breast cancer metastatic to the iris with secondary neovascular glaucoma provided good local control for a limited follow-up period, because the patient died because of systemic complications of her disease.
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- 2017
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30. Weekly versus every-three-weeks platinum-based chemoradiation regimens for head and neck cancer.
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Melotek JM, Cooper BT, Koshy M, Silverman JS, and Spiotto MT
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- Chicago, Female, Head and Neck Neoplasms mortality, Humans, Male, Middle Aged, Survival Rate, Treatment Outcome, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Carboplatin administration & dosage, Chemoradiotherapy methods, Cisplatin administration & dosage, Head and Neck Neoplasms therapy
- Abstract
Background: The majority of chemoradiation (CRT) trials for locally advanced head and neck squamous cell carcinoma (HNSCC) have relied on platinum-based chemotherapy regimens administered every-3-weeks. However, given the increased utilization of weekly platinum regimens, it remains unclear how different chemotherapy schedules compare regarding efficacy and toxicity., Methods: We retrospectively identified 212 patients with HNSCC who were treated at a single academic medical center with concurrent platinum-based CRT given weekly (N = 68) or every-three-weeks (N = 144). JMP version 10 (SAS Institute) was used for statistical analysis. Discrete variables were compared with the chi-square test and differences in the medians were assessed using the Wilcoxon test. Survival curves were constructed using the Kaplan-Meier method and significance was assessed using the log rank test. For univariate analysis and multivariate analysis, we used Cox proportional hazard or logistic regression models to compare differences in survival or differences in categorical variables, respectively., Results: Patients receiving weekly platinum regimens were more likely to be older (median age 61.4 vs. 55.5 y; P < .001), have high or very high Charlson comorbidity index (45.6% vs. 27.8%; P = .01), and receive carboplatin-based chemotherapy (6.3% vs. 76.5%; P < .001). Weekly and every-3-week platinum regimens had similar locoregional control (HR 1.10; 95% CI 0.63-1.88; P = .72), progression-free survival (HR 1.13; 95% CI 0.75-1.69; P = .55), and overall survival (HR 1.11; 95% CI 0.64-1.86; P = .71). Every-3-weeks platinum regimens were associated with increased days of hospitalization (median: 3 days vs. 0 days; P = .03) and acute kidney injury (AKI) during radiotherapy (50.0% vs. 22.1%; P < .001). On multivariate analysis, AKI was significantly associated with every-3-weeks regimens (OR: 24.38; 95% CI 3.00-198.03; P = .003) and high comorbidity scores (OR: 2.74; 95% CI 2.15-5.99; P = .01)., Conclusions: Our results suggest that every-3-weeks and weekly platinum-containing CRT regimens have similar disease control but weekly platinum regimens are associated with less acute toxicity.
- Published
- 2016
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31. Impact on overall survival of the combination of BRAF inhibitors and stereotactic radiosurgery in patients with melanoma brain metastases.
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Wolf A, Zia S, Verma R, Pavlick A, Wilson M, Golfinos JG, Silverman JS, and Kondziolka D
- Subjects
- Aged, Brain Neoplasms secondary, Brain Neoplasms therapy, Combined Modality Therapy, Female, Follow-Up Studies, Humans, Male, Melanoma pathology, Melanoma therapy, Middle Aged, Mutation genetics, Neoplasm Staging, Prognosis, Prospective Studies, Proto-Oncogene Proteins B-raf genetics, Survival Rate, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Brain Neoplasms mortality, Melanoma mortality, Proto-Oncogene Proteins B-raf antagonists & inhibitors, Radiosurgery mortality
- Abstract
The aim of this study was to evaluate the impact of BRAF inhibitors on survival outcomes in patients receiving stereotactic radiosurgery (SRS) for melanoma brain metastases. We prospectively collected treatment parameters and outcomes for 80 patients with melanoma brain metastases who underwent SRS. Thirty-five patients harbored the BRAF mutation (BRAF-M) and 45 patients did not (BRAF-WT). Univariate and multivariate analyses were performed to identify predictors of overall survival. The median overall survival from first SRS procedure was 6.7, 11.2 months if treated with a BRAF inhibitor and 4.5 months for BRAF-WT. Actuarial survival rates for BRAF-M patients on an inhibitor were 54 % at 6 months and 41 % at 12 months from the time of SRS. In contrast, BRAF-WT had overall survival rates of 28 % at 6 months and 19 % at 12 months. Overall survival was extended for patients on a BRAF inhibitor at or after the first SRS. The median time to intracranial progression was 3.9 months on a BRAF inhibitor and 1.7 months without. The local control rate for all treated tumors was 92.5 %, with no difference based on BRAF status. Patients with higher KPS, fewer treated intracranial metastases, controlled systemic disease, RPA Class 1 and BRAF-M patients had extended overall survival. Overall, patients with BRAF-M treated with both SRS and BRAF inhibitors, at or after SRS, have increased overall survival from the time of SRS. As patients live longer as a result of more effective systemic and local therapies, close surveillance and early management of intracranial disease with SRS will become increasingly important.
- Published
- 2016
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32. Survival but not brain metastasis response relates to lung cancer mutation status after radiosurgery.
- Author
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Shin SM, Cooper BT, Chachoua A, Butler J, Donahue B, Silverman JS, and Kondziolka D
- Subjects
- Adenocarcinoma mortality, Adenocarcinoma pathology, Adenocarcinoma surgery, Adult, Aged, Aged, 80 and over, Brain Neoplasms mortality, Brain Neoplasms secondary, Brain Neoplasms surgery, Carcinoma, Neuroendocrine mortality, Carcinoma, Neuroendocrine pathology, Carcinoma, Neuroendocrine surgery, Carcinoma, Non-Small-Cell Lung mortality, Carcinoma, Non-Small-Cell Lung pathology, Carcinoma, Non-Small-Cell Lung surgery, Carcinoma, Squamous Cell mortality, Carcinoma, Squamous Cell pathology, Carcinoma, Squamous Cell surgery, ErbB Receptors genetics, Female, Follow-Up Studies, Humans, Lung Neoplasms genetics, Lung Neoplasms mortality, Lung Neoplasms pathology, Lung Neoplasms surgery, Male, Middle Aged, Neoplasm Staging, Prognosis, Prospective Studies, Survival Rate, Adenocarcinoma genetics, Brain Neoplasms genetics, Carcinoma, Neuroendocrine genetics, Carcinoma, Non-Small-Cell Lung genetics, Carcinoma, Squamous Cell genetics, Mutation genetics, Radiosurgery mortality
- Abstract
We prospectively addressed whether EGFR and KRAS mutations, EML4-ALK, ROS1 and RET rearrangements, or wild-type (WT), affects radiosurgery outcomes and overall survival (OS) in non-small cell lung cancer (NSCLC) patients with brain metastases (BM). Of 326 patients with BM treated in 2012-2014 with Gamma Knife radiosurgery (GKRS), 112 NSCLC patients received GKRS as their initial intracranial treatment. OS, intracranial progression-free survival, and time to intracranial failure were determined. Univariate and multivariate analysis were performed to determine factors affecting OS. Toxicity of treatment was evaluated. Median follow-up was 9 months. Patients with EGFR mutant BM had improved survival compared to WT. Median time to development of BM was higher in EGFR mutant patients, but this difference was not significant (2.2 vs 0.9 months; p = 0.2). Median time to distant brain failure was independent of EGFR mutation status. Karnofsky performance status (KPS), non-squamous histopathology, targeted therapy, systemic disease control, EGFR mutation, and low tumor volume were predictive of increased OS on univariate analysis. KPS (p = 0.001) and non-squamous histopathology (p = 0.03) continued to be significant on multivariate analysis. Patients with EGFR mutant BM underwent salvage treatment more often than those without (p = 0.04). Treatment-related toxicity was no different in patients treated with GKRS combined with targeted therapies versus GKRS alone (5 vs 7%, p = 0.7). Patients with EGFR mutant BM had improved survival compared to a WT cohort. Intracranial disease control following radiosurgery was similar for all tumor subtypes. Radiosurgery is effective for BM and concurrent treatment with targeted therapy appears to be safe.
- Published
- 2016
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33. Resection Followed by Involved-Field Fractionated Radiotherapy in the Management of Single Brain Metastasis.
- Author
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Shin SM, Vatner RE, Tam M, Golfinos JG, Narayana A, Kondziolka D, and Silverman JS
- Abstract
Introduction: We expanded upon our previous experience using involved-field fractionated radiotherapy (IFRT) as an alternative to whole brain radiotherapy or stereotactic radiosurgery for patients with surgically resected brain metastases (BM)., Materials and Methods: All patients with single BM who underwent surgical resection followed by IFRT at our institution from 2006 to 2013 were evaluated. Local recurrence (LR)-free survival, distant failure (DF)-free survival, and overall survival (OS) were determined. Analyses were performed associating clinical variables with LR and DF. Salvage approaches and toxicity of treatment for each patient were also assessed., Results: Median follow-up was 19.1 months. Fifty-six patients were treated with a median dose of 40.05 Gy/15 fractions with IFRT to the resection cavity. LR-free survival was 91.4%, DF-free survival was 68.4%, and OS was 77.7% at 12 months. No variables were associated with increased LR; however, melanoma histopathology and infratentorial location were associated with DF on multivariate analysis. LRs were salvaged in 5/8 patients, and DFs were salvaged in 24/29 patients. Two patients developed radionecrosis., Conclusion: Adjuvant IFRT is feasible and safe for well-selected patients with surgically resected single BM. Acceptable rates of local control and salvage of distal intracranial recurrences continue to be achieved with continued follow-up.
- Published
- 2015
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34. The biology of radiosurgery and its clinical applications for brain tumors.
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Kondziolka D, Shin SM, Brunswick A, Kim I, and Silverman JS
- Subjects
- Glioma physiopathology, Glioma surgery, Humans, Meningioma physiopathology, Meningioma surgery, Neoplasm Metastasis physiopathology, Neuroectodermal Tumors physiopathology, Neuroectodermal Tumors surgery, Treatment Outcome, Brain Neoplasms physiopathology, Brain Neoplasms surgery, Radiosurgery methods
- Abstract
Stereotactic radiosurgery (SRS) was developed decades ago but only began to impact brain tumor care when it was coupled with high-resolution brain imaging techniques such as computed tomography and magnetic resonance imaging. The technique has played a key role in the management of virtually all forms of brain tumor. We reviewed the radiobiological principles of SRS on tissue and how they pertain to different brain tumor disorders. We reviewed the clinical outcomes on the most common indications. This review found that outcomes are well documented for safety and efficacy and show increasing long-term outcomes for benign tumors. Brain metastases SRS is common, and its clinical utility remains in evolution. The role of SRS in brain tumor care is established. Together with surgical resection, conventional radiotherapy, and medical therapies, patients have an expanding list of options for their care. Clinicians should be familiar with radiosurgical principles and expected outcomes that may pertain to different brain tumor scenarios., (© The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2015
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35. Feasibility and efficacy of local radiotherapy with concurrent novel agents in patients with multiple myeloma.
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Shin SM, Chouake RJ, Sanfilippo NJ, Rapp TB, Cook P, Formenti SC, Mazumder A, and Silverman JS
- Subjects
- Adult, Aged, Aged, 80 and over, Bone Marrow Transplantation, Chemoradiotherapy adverse effects, Combined Modality Therapy, Female, Humans, Immunoglobulin kappa-Chains blood, Male, Middle Aged, Multiple Myeloma blood, Multiple Myeloma pathology, Neoplasm Staging, Radiotherapy Dosage, Treatment Outcome, Multiple Myeloma therapy
- Abstract
Introduction: This study evaluated the safety and efficacy of radiotherapy (RT) with concurrent novel agents (NAs), cytotoxic therapy (CTx), or both in the management of osteolytic bone lesions in multiple myeloma (MM)., Patients and Methods: A total of 39 patients with MM received RT to 64 different bone sites during the 2007-2012 period, with a dose of 8 to 37.5 Gy (mean, 26.8 Gy) delivered in 1 to 15 fractions (median, 10 fractions). Of these patients, 21 also received concurrent NAs or CTx. Pain response, M protein and κ light chain response, and adverse events were evaluated., Results: RT was completed in 35 of 39 patients (89.7%) in this study. Pain relief was observed in 30 of 31 patients (96.7%). Hematologic toxicity (grade 3 or 4 by the Radiation Therapy Oncology Group system) was seen in 43.2% of treated patients, and NA therapy was stopped in 2 patients owing to grade 4 toxicity. RT adverse effects resolved at 4 to 6 weeks posttreatment. Changes in pre- and posttreatment levels of M protein trended toward significance in patients treated with RT + systemic therapy (ST) versus. RT alone (ΔM ProteinRT+ST = 5.6 g/L; ΔM ProteinRT = 0 g/L; P = .089)., Conclusion: Treating MM with RT concurrently with CTx including NAs was safe and well tolerated in the majority of patients (14 of 16 [87.5%] for those taking NAs and 19 of 21 [90.5%] for all patients). Excellent clinical pain response (> 95%) was also seen in patients regardless if they were treated with RT + ST or RT alone., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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36. "Right Here is the Gateway": Mobility, Sex Work Entry and HIV Risk Along the Mexico-U.S. Border.
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Goldenberg S, Silverman J, Engstrom D, Bojorquez-Chapela I, and Strathdee S
- Abstract
Women comprise an increasing proportion of migrants. Many voluntarily migrate for sex work or practice survival sex, while others may be trafficked for sexual exploitation. To investigate how the context of mobility shapes sex work entry and HIV risk, we conducted in-depth interviews with formerly trafficked women currently engaged in sex work (n=31) in Tijuana, Mexico and their service providers (n=7) in Tijuana and San Diego, USA from 2010-2011. Women's experiences of coerced and deceptive migration, deportation as forced migration, voluntary mobility, and migration to a risk environment illustrate that circumstances driving and resulting from migration shape vulnerability to sex trafficking, voluntary sex work entry, and HIV risk. Findings suggest an urgent need for public health and immigration policies that provide integrated support for deported and/or recently arrived female migrants. Policies to prevent sex trafficking and assist trafficked females must also consider the varying levels of personal agency involved in migration and sex work entry.
- Published
- 2014
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37. Characterization of the late endosomal ESCRT machinery in Trypanosoma brucei.
- Author
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Silverman JS, Muratore KA, and Bangs JD
- Subjects
- Lysosomes metabolism, Membrane Glycoproteins metabolism, Membrane Proteins metabolism, Multivesicular Bodies metabolism, Protein Transport, Transport Vesicles metabolism, Trypanosoma brucei brucei physiology, Ubiquitin metabolism, Endosomal Sorting Complexes Required for Transport metabolism, Endosomes metabolism, Trypanosoma brucei brucei metabolism
- Abstract
The multivesicular body (MVB) is a specialized Rab7+ late endosome (LE) containing multiple intralumenal vesicles that function in targeting ubiquitinylated cell surface proteins to the lysosome for degradation. African trypanosomes lack a morphologically well-defined MVB, but contain orthologs of the ESCRT (Endosomal Sorting Complex Required for Transport) machinery that mediates MVB formation. We investigate the role of TbVps23, an early ESCRT component, and TbVps4, the terminal ESCRT ATPase, in lysosomal trafficking in bloodstream form trypanosomes. Both localize to the TbRab7+ LE and RNAi silencing of each rapidly blocks growth. TbVps4 silencing results in approximately threefold accumulation of TbVps23 at the LE, consistent with blocking terminal ESCRT disassembly. Trafficking of endocytic and biosynthetic cargo, but not default lysosomal reporters, is also negatively affected. Others reported that TbVps23 mediates ubiquitin-dependent lysosomal degradation of invariant surface glycoproteins (ISG65) (Leung et al., Traffic 2008;9:1698-1716). In contrast, we find that TbVps23 ablation does not affect ISG65 turnover, while TbVps4 silencing markedly enhances lysosomal degradation. We propose several models to accommodate these results, including that the ESCRT machinery actually retrieves ISG65 from the LE to earlier endocytic compartments, and in its absence ISG65 traffics more efficiently to the lysosome. Overall, these results confirm that the ESCRT machinery is essential in Trypanosoma brucei and plays important and novel role(s) in LE function in trypanosomes., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2013
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38. Form and function in the trypanosomal secretory pathway.
- Author
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Silverman JS and Bangs JD
- Subjects
- Animals, Endoplasmic Reticulum metabolism, Golgi Apparatus metabolism, Humans, Lysosomes metabolism, Multivesicular Bodies metabolism, Protein Transport, Trypanosoma brucei brucei ultrastructure, Trypanosomiasis, African metabolism, Variant Surface Glycoproteins, Trypanosoma immunology, Variant Surface Glycoproteins, Trypanosoma metabolism, Secretory Pathway physiology, Trypanosoma brucei brucei metabolism, Trypanosomiasis, African parasitology
- Abstract
Recent advances in secretory biology of African trypanosomes reveal both similarities and striking differences with other model eukaryotic organisms. Secretion is streamlined for rapid and selective transport of the major cargo, VSG. Selectivity in the early and post-Golgi compartments is dependent on glycosylphosphatidyl inositol anchors. Streamlining includes reduced organellar abundance, and close association of ER exit sites with Golgi and with unique flagellar cytoskeletal elements that govern organellar replication and segregation. These elements include a novel centrin containing bilobe structure. Innate signals for post-Golgi sorting of biosynthetic lysosomal cargo trafficking have been defined, as have pathways for both biosynthetic and endocytic trafficking to the lysosome. Less well-defined secretory organelles such as the multivesicular body and acidocalcisomes are receiving closer scrutiny., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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39. SCF ubiquitin ligases in the maintenance of genome stability.
- Author
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Silverman JS, Skaar JR, and Pagano M
- Subjects
- Animals, DNA Damage, Humans, SKP Cullin F-Box Protein Ligases genetics, SKP Cullin F-Box Protein Ligases metabolism, Ubiquitination genetics, Genomic Instability, SKP Cullin F-Box Protein Ligases chemistry
- Abstract
In response to genotoxic stress, eukaryotic cells activate the DNA damage response (DDR), a series of pathways that coordinate cell cycle arrest and DNA repair to prevent deleterious mutations. In addition, cells possess checkpoint mechanisms that prevent aneuploidy by regulating the number of centrosomes and spindle assembly. Among these mechanisms, ubiquitin-mediated degradation of key proteins has an important role in the regulation of the DDR, centrosome duplication and chromosome segregation. This review discusses the functions of a group of ubiquitin ligases, the SCF (SKP1-CUL1-F-box protein) family, in the maintenance of genome stability. Given that general proteasome inhibitors are currently used as anticancer agents, a better understanding of the ubiquitylation of specific targets by specific ubiquitin ligases may result in improved cancer therapeutics., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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40. Late endosomal Rab7 regulates lysosomal trafficking of endocytic but not biosynthetic cargo in Trypanosoma brucei.
- Author
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Silverman JS, Schwartz KJ, Hajduk SL, and Bangs JD
- Subjects
- Endosomes metabolism, Gene Knockdown Techniques, Lectins metabolism, Lysosomes metabolism, Trypanosoma brucei brucei genetics, Trypanosoma brucei brucei metabolism, rab GTP-Binding Proteins genetics, rab7 GTP-Binding Proteins, Endocytosis, Endosomes physiology, Lysosomes physiology, Protozoan Proteins metabolism, Trypanosoma brucei brucei physiology, rab GTP-Binding Proteins metabolism
- Abstract
We present the first functional analysis of the small GTPase, TbRab7, in Trypanosoma brucei. TbRab7 defines discrete late endosomes closely juxtaposed to the terminal p67(+) lysosome. RNAi indicates that TbRab7 is essential in bloodstream trypanosomes. Initial rates of endocytosis were unaffected, but lysosomal delivery of cargo, including tomato lectin (TL) and trypanolytic factor (TLF) were blocked. These accumulate in a dispersed internal compartment of elevated pH, likely derived from the late endosome. Surface binding of TL but not TLF was reduced, suggesting that cellular distribution of flagellar pocket receptors is differentially regulated by TbRab7. TLF activity was reduced approximately threefold confirming that lysosomal delivery is critical for trypanotoxicity. Unexpectedly, delivery of endogenous proteins, p67 and TbCatL, were unaffected indicating that TbRab7 does not regulate biosynthetic lysosomal trafficking. Thus, unlike mammalian cells and yeast, lysosomal trafficking of endocytosed and endogenous proteins occur via different routes and/or are regulated differentially. TbRab7 silencing had no effect on a cryptic default pathway to the lysosome, suggesting that the default lysosomal reporters p67ΔTM, p67ΔCD and VSGΔGPI do not utilize the endocytic pathway as previously proposed. Surprisingly, conditional knockout indicates that TbRab7 may be non-essential in procyclic insect form trypanosomes., (© 2011 Blackwell Publishing Ltd.)
- Published
- 2011
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41. Decreased Posttreatment SUV on PET Scan Is Associated With Improved Local Control in Medically Inoperable Esophageal Cancer.
- Author
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Sharma NK, Silverman JS, Li T, Cheng J, Yu JQ, Haluszka O, Scott W, Meropol NJ, Cohen SJ, Freedman GM, and Konski AA
- Abstract
Background: The relationship between local, regional, or distant disease control (LC, RC, DC) and maximal posttreatment standardized uptake value (SUV(max)) in patients with esophageal cancer has not been elucidated. This study was initiated to explore whether a decrease in SUV on positron emission tomography-computed tomography (PET-CT) scan is associated with LC, RC, or DC in patients with esophageal carcinoma treated with definitive chemoradiotherapy., Methods: Medical records of 40 patients with inoperable esophageal cancer treated with definitive intent and who underwent pre- and posttreatment PET-CT scans were reviewed. The histology, nodal status, tumor location, and radiotherapy (RT) dose were investigated as variables to determine a relationship between SUV(max) and LC, RC, and DC as well as disease-free survival (DFS)., Results: Decreased posttreatment SUV(max) on PET scan (P = .02) and increased RT dose (P = .009) were the only significant predictors of improved LC on univariate analysis. Mean RT doses in patients with no evidence of disease or with local, regional, or distant recurrences were 5,244, 4,580, 5,094, and 4,968, respectively. Decreased posttreatment SUV (P = .03) and increased RT dose (P = .008) were also associated with an improvement in DFS. Furthermore, decreased posttreatment SUV(max) correlated with an improvement in LC (hazard ratio [HR] = 1.3, 95% confidence interval [CI] = 1.03-1.6, P = .03) as well as DFS (HR = 1.3, 95% CI = 1.03-1.6, P = .03). These findings were maintained on multivariate analysis., Conclusions: Posttreatment decrease in SUV is associated with LC and DFS in esophageal cancer patients receiving definitive chemoradiotherapy. RT dose was also associated with both LC and DFS. The prognostic significance of these findings warrants prospective confirmation.
- Published
- 2011
42. A double-blind, randomized, controlled clinical trial evaluating the efficacy and tolerance of a novel phenolic antioxidant skin care system containing Coffea arabica and concentrated fruit and vegetable extracts.
- Author
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Palmer DM and Kitchin JS
- Subjects
- Administration, Topical, Antioxidants adverse effects, Coffea, Double-Blind Method, Emollients, Face, Female, Flavonoids adverse effects, Fruit, Humans, Middle Aged, Phenols adverse effects, Phytotherapy, Plant Extracts adverse effects, Polyphenols, Skin, Skin Care adverse effects, Vegetables, Antioxidants therapeutic use, Flavonoids therapeutic use, Hyperpigmentation drug therapy, Phenols therapeutic use, Plant Extracts therapeutic use, Skin Aging drug effects, Skin Care methods
- Abstract
Objective: This 12-week, double-blinded, randomized, controlled clinical usage study was conducted to evaluate the efficacy and tolerance of a novel topical, multi-ingredient, polyphenol, high antioxidant skin care system (facial wash, day lotion, night crème and eye serum) to reduce the appearance of photoaging., Methods: A total of 40 Caucasian female participants were randomly assigned to apply the test regimen or control regimen for 12 weeks. One group washed with the test antioxidant facial wash twice daily, applied the test antioxidant day lotion each morning and the test antioxidant night creme and eye serum each evening. The second group washed with a control facial wash twice daily and applied a control moisturizer each morning and evening. Clinical evaluations for efficacy were made by a board-certified dermatologist at baseline and after six and 12 weeks of product use. Efficacy was also measured by subjects' self-assessments and via photography and instrumentation., Results and Conclusion: Overall, the results of the study showed that the test regimen produced statistically significant improvements in the appearance of photodamaged skin. Most impressive was the significantly greater improvements produced by the test regimen over the control regimen for nearly every grading parameter. The results from this study demonstrate that this high Total ORACsc scoring antioxidant skin care system was well tolerated, with no adverse events reported by the participants during the course of the study, and improved, significantly greater than a control regimen, the appearance of wrinkles, firmness, hyperpigmentation, blotchy redness, tactile roughness and clarity in photodamaged skin. Post-baseline clinical grading scores, silicone replica parameters, cutometer and corneometer scores were statistically compared to baseline using a paired t test at the P?0.05 significance level.
- Published
- 2010
43. Synthetic lethal screen of an EGFR-centered network to improve targeted therapies.
- Author
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Astsaturov I, Ratushny V, Sukhanova A, Einarson MB, Bagnyukova T, Zhou Y, Devarajan K, Silverman JS, Tikhmyanova N, Skobeleva N, Pecherskaya A, Nasto RE, Sharma C, Jablonski SA, Serebriiskii IG, Weiner LM, and Golemis EA
- Subjects
- Aurora Kinase A, Aurora Kinases, Cytotoxins genetics, ErbB Receptors antagonists & inhibitors, ErbB Receptors genetics, Protein Kinase C metabolism, Protein Serine-Threonine Kinases metabolism, RNA Interference, RNA, Small Interfering genetics, STAT3 Transcription Factor metabolism, Cytotoxins metabolism, Drug Discovery methods, Drug Resistance, Neoplasm genetics, ErbB Receptors metabolism, Neoplasms drug therapy, Protein Interaction Mapping methods, Signal Transduction genetics
- Abstract
Intrinsic and acquired cellular resistance factors limit the efficacy of most targeted cancer therapeutics. Synthetic lethal screens in lower eukaryotes suggest that networks of genes closely linked to therapeutic targets would be enriched for determinants of drug resistance. We developed a protein network centered on the epidermal growth factor receptor (EGFR), which is a validated cancer therapeutic target, and used small interfering RNA screening to comparatively probe this network for proteins that regulate the effectiveness of both EGFR-targeted agents and nonspecific cytotoxic agents. We identified subnetworks of proteins influencing resistance, with putative resistance determinants enriched among proteins that interacted with proteins at the core of the network. We found that clinically relevant drugs targeting proteins connected in the EGFR network, such as protein kinase C or Aurora kinase A, or the transcriptional regulator signal transducer and activator of transcription 3 (STAT3), synergized with EGFR antagonists to reduce cell viability and tumor size, suggesting the potential for a direct path to clinical exploitation. Such a focused approach can potentially improve the coherent design of combination cancer therapies.
- Published
- 2010
- Full Text
- View/download PDF
44. Multiple Functional Variants in cis Modulate PDYN Expression.
- Author
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Babbitt CC, Silverman JS, Haygood R, Reininga JM, Rockman MV, and Wray GA
- Subjects
- Alleles, Binding Sites, Cell Line, Tumor, Genotype, Humans, Polymorphism, Genetic, Reverse Transcriptase Polymerase Chain Reaction, Enkephalins genetics, Genetic Variation, Protein Precursors genetics, Regulatory Sequences, Nucleic Acid genetics
- Abstract
Understanding genetic variation and its functional consequences within cis-regulatory regions remains an important challenge in human genetics and evolution. Here, we present a fine-scale functional analysis of segregating variation within the cis-regulatory region of prodynorphin, a gene that encodes an endogenous opioid precursor with roles in cognition and disease. In order to characterize the functional consequences of segregating variation in cis in a region under balancing selection in different human populations, we examined associations between specific polymorphisms and gene expression in vivo and in vitro. We identified five polymorphisms within the 5' flanking region that affect transcript abundance: a 68-bp repeat recognized in prior studies, as well as two microsatellites and two single nucleotide polymorphisms not previously implicated as functional variants. The impact of these variants on transcription differs by brain region, sex, and cell type, implying interactions between cis genotype and the differentiated state of cells. The effects of individual variants on expression level are not additive in some combinations, implying epistatic interactions between nearby variants. These data reveal an unexpectedly complex relationship between segregating genetic variation and its expression-trait consequences and highlights the importance of close functional scrutiny of natural genetic variation within even relatively well-studied cis-regulatory regions.
- Published
- 2010
- Full Text
- View/download PDF
45. Oxidative damage, skin aging, antioxidants and a novel antioxidant rating system.
- Author
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Palmer DM and Kitchin JS
- Subjects
- Administration, Topical, Animals, Antioxidants administration & dosage, Antioxidants chemistry, Antioxidants metabolism, Humans, Light, Oxidation-Reduction, Oxidative Stress drug effects, Oxidative Stress physiology, Reactive Oxygen Species chemistry, Skin chemistry, Skin drug effects, Sunscreening Agents pharmacology, Antioxidants pharmacology, Skin Aging drug effects
- Abstract
It is believed that oxidative stress is caused by an imbalance between the production of reactive oxygen and a biological system's ability to neutralize the reactive intermediates. Oxidative damage occurs because of both intrinsic and extrinsic mechanisms. Together, intrinsic and extrinsic damage are the primary causes of skin aging. The skin uses a series of intrinsic antioxidants to protect itself from free radical damage. Naturally occurring extrinsic antioxidants have also been widely shown to offset and alleviate these changes. Unlike sunscreens, which have an SPF rating system to guide consumers in their purchases, there is no widely accepted method to choose antioxidant anti-aging products. ORAC (Oxygen Radical Absorbance Capacity) and ABEL-RAC (Analysis By Emitted Light-Relative Antioxidant Capacity), are both accepted worldwide as a standard measure of the antioxidant capacity of foods, and are rating systems that could be applied to all antioxidant skincare products. The standardization of antioxidant creams could revolutionize the cosmeceutical market and give physicians and consumers the ability to compare and choose effectively.
- Published
- 2010
46. Role of AP-1 in developmentally regulated lysosomal trafficking in Trypanosoma brucei.
- Author
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Tazeh NN, Silverman JS, Schwartz KJ, Sevova ES, Sutterwala SS, and Bangs JD
- Subjects
- Adaptor Protein Complex 1 genetics, Animals, Gene Silencing, Humans, Lysosomes parasitology, Protein Subunits genetics, Protein Subunits metabolism, Protein Transport, Protozoan Proteins genetics, Trypanosoma brucei brucei genetics, Trypanosomiasis, African parasitology, Adaptor Protein Complex 1 metabolism, Lysosomes metabolism, Protozoan Proteins metabolism, Trypanosoma brucei brucei growth & development, Trypanosoma brucei brucei metabolism, Trypanosomiasis, African metabolism
- Abstract
African trypanosomes are the causative agents of human trypanosomiasis (sleeping sickness). The pathogenic stage of the parasite has unique adaptations to life in the bloodstream of the mammalian host, including upregulation of endocytic and lysosomal activities. We investigated stage-specific requirements for cytoplasmic adaptor/clathrin machinery in post-Golgi apparatus biosynthetic sorting to the lysosome using RNA interference silencing of the Tbmu1 subunit of adaptor complex 1 (AP-1), in conjunction with immunolocalization, kinetic analyses of reporter transport, and quantitative endocytosis assays. Tbmu1 silencing was lethal in both stages, indicating a critical function(s) for the AP-1 machinery. Transport of soluble and membrane-bound secretory cargoes was Tbmu1 independent in both stages. In procyclic parasites, trafficking of the lysosomal membrane protein, p67, was disrupted, leading to cell surface mislocalization. The lysosomal protease trypanopain was also secreted, suggesting a transmembrane-sorting receptor for this soluble hydrolase. In bloodstream trypanosomes, both p67 and trypanopain trafficking were unaffected by Tbmu1 silencing, suggesting that AP-1 is not necessary for biosynthetic lysosomal trafficking. Endocytosis in bloodstream cells was also unaffected, indicating that AP-1 does not function at the flagellar pocket. These results indicate that post-Golgi apparatus sorting to the lysosome is critically dependent on the AP-1/clathrin machinery in procyclic trypanosomes but that this machinery is not necessary in bloodstream parasites. We propose a simple model for stage-specific default secretory trafficking in trypanosomes that is consistent with the behavior of other soluble and glycosylphosphatidylinositol-anchored cargos and which is influenced by upregulation of endocytosis in bloodstream parasites as an adaptation to life in the mammalian bloodstream.
- Published
- 2009
- Full Text
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47. Targeting EGFR resistance networks in head and neck cancer.
- Author
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Ratushny V, Astsaturov I, Burtness BA, Golemis EA, and Silverman JS
- Subjects
- Antibodies, Monoclonal therapeutic use, Apoptosis, Carcinoma, Squamous Cell drug therapy, Cell Cycle, Drug Resistance, Neoplasm, ErbB Receptors metabolism, Head and Neck Neoplasms drug therapy, Humans, Protein Kinase Inhibitors metabolism, Carcinoma, Squamous Cell metabolism, ErbB Receptors antagonists & inhibitors, Head and Neck Neoplasms metabolism
- Abstract
A core set of oncoproteins is overexpressed or functionally activated in many types of cancer, and members of this group have attracted significant interest as subjects for development of targeted therapeutics. For some oncoproteins such as EGFR/ErbB1, both small molecule and antibody agents have been developed and applied in the clinic for over a decade. Analysis of clinical outcomes has revealed an initially unexpected complexity in the response of patients to these agents. Diverse factors, including developmental lineage of the tumor progenitor cell, co-mutation or epigenetic modulation of genes encoding proteins in an extended EGFR signaling network or regulating core survival responses in individual tumors, and environmental factors including inflammatory agents and viral infection, all have been identified as modulating response to treatment with EGFR-targeted drugs. Second and third generation therapeutic strategies increasingly incorporate knowledge of cancer type-specific signaling environments, in a more personalized treatment approach. This review takes squamous cell carcinoma of the head and neck (SCCHN) as a specific example of an EGFR-involved cancer with idiosyncratic biological features that influence design of treatment modalities, with particular emphasis on commonalities and differences with other cancer types.
- Published
- 2009
- Full Text
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48. Identification of functional Tat signal sequences in Mycobacterium tuberculosis proteins.
- Author
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McDonough JA, McCann JR, Tekippe EM, Silverman JS, Rigel NW, and Braunstein M
- Subjects
- Bacterial Proteins genetics, Bacterial Proteins metabolism, Immunoblotting, Membrane Transport Proteins genetics, Membrane Transport Proteins metabolism, Membrane Transport Proteins physiology, Models, Genetic, Mycobacterium tuberculosis genetics, Mycobacterium tuberculosis metabolism, Open Reading Frames genetics, Plasmids genetics, Protein Transport, Signal Transduction, Type C Phospholipases genetics, Type C Phospholipases metabolism, Type C Phospholipases physiology, Arginine metabolism, Bacterial Proteins physiology, Mycobacterium tuberculosis physiology
- Abstract
The twin-arginine translocation (Tat) pathway is a system used by some bacteria to export proteins out from the cytosol to the cell surface or extracellular environment. A functional Tat pathway exists in the important human pathogen Mycobacterium tuberculosis. Identification of the substrates exported by the Tat pathway can help define the role that this pathway plays in the physiology and pathogenesis of M. tuberculosis. Here we used a reporter of Tat export, a truncated beta-lactamase, 'BlaC, to experimentally identify M. tuberculosis proteins with functional Tat signal sequences. Of the 13 proteins identified, one lacks the hallmark of a Tat-exported substrate, the twin-arginine dipeptide, and another is not predicted by in silico analysis of the annotated M. tuberculosis genome. Full-length versions of a subset of these proteins were tested to determine if the native proteins are Tat exported. For three proteins, expression in a Deltatat mutant of Mycobacterium smegmatis revealed a defect in precursor processing compared to expression in the wild type, indicating Tat export of the full-length proteins. Conversely, two proteins showed no obvious Tat export in M. smegmatis. One of this latter group of proteins was the M. tuberculosis virulence factor phospholipase C (PlcB). Importantly, when tested in M. tuberculosis a different result was obtained and PlcB was exported in a twin-arginine-dependent manner. This suggests the existence of an M. tuberculosis-specific factor(s) for Tat export of a proven virulence protein. It also emphasizes the importance of domains beyond the Tat signal sequence and bacterium-specific factors in determining if a given protein is Tat exported.
- Published
- 2008
- Full Text
- View/download PDF
49. Convergent adaptation of human lactase persistence in Africa and Europe.
- Author
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Tishkoff SA, Reed FA, Ranciaro A, Voight BF, Babbitt CC, Silverman JS, Powell K, Mortensen HM, Hirbo JB, Osman M, Ibrahim M, Omar SA, Lema G, Nyambo TB, Ghori J, Bumpstead S, Pritchard JK, Wray GA, and Deloukas P
- Subjects
- Adult, Africa, Animals, Caco-2 Cells, Europe, Evolution, Molecular, Gene Frequency, Haplotypes, Humans, Lactose blood, Lactose Tolerance Test, Milk metabolism, Polymorphism, Single Nucleotide, Selection, Genetic, Adaptation, Biological, Lactase genetics, Lactose metabolism
- Abstract
A SNP in the gene encoding lactase (LCT) (C/T-13910) is associated with the ability to digest milk as adults (lactase persistence) in Europeans, but the genetic basis of lactase persistence in Africans was previously unknown. We conducted a genotype-phenotype association study in 470 Tanzanians, Kenyans and Sudanese and identified three SNPs (G/C-14010, T/G-13915 and C/G-13907) that are associated with lactase persistence and that have derived alleles that significantly enhance transcription from the LCT promoter in vitro. These SNPs originated on different haplotype backgrounds from the European C/T-13910 SNP and from each other. Genotyping across a 3-Mb region demonstrated haplotype homozygosity extending >2.0 Mb on chromosomes carrying C-14010, consistent with a selective sweep over the past approximately 7,000 years. These data provide a marked example of convergent evolution due to strong selective pressure resulting from shared cultural traits-animal domestication and adult milk consumption.
- Published
- 2007
- Full Text
- View/download PDF
50. Detection of attomole quantities [correction of quantitites] of DNA targets on gold microelectrodes by electrocatalytic nucleobase oxidation.
- Author
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Gore MR, Szalai VA, Ropp PA, Yang IV, Silverman JS, and Thorp HH
- Subjects
- Catalysis, DNA genetics, Electrochemistry, Microelectrodes, Oligonucleotide Probes genetics, DNA analysis, Gold analysis, Oligonucleotide Probes analysis
- Abstract
The electrochemical detection of nucleic acid targets at low concentrations has a number of applications in diagnostics and pharmaceutical research. Self-assembled monolayers of alkanethiol-derivatized oligonucleotides on gold electrodes provide a useful platform for such detectors, and the electrocatalytic oxidation of nucleobases included in the DNA targets is a particularly sensitive method of electrochemical detection. A strategy has been developed for combining these two aspects by substituting either 7,8-dihydro-8-oxoguanine (8G) or 5-aminouridine (5U) into DNA targets. Upon hybridization of targets containing these modified nucleobases, electrocatalytic signals at probe-modified gold electrodes are observed in the presence of Os(bpy)(3)(2+), which oxidizes both 8G and 5U upon oxidation to the Os(III) state. Self-assembled monolayers were prepared on both macro (1.6 mm) and micro (25 microm) gold electrodes using published procedures involving C6-terminated alkanethiol oligonucleotides and mercaptohexanol as the diluent. The extent of electrode modification by the modified probe was assessed using radiolabeling and a standard chronocoulometry method; both approaches gave loading levels within expected ranges ((1-6) x 10(12) molecules/cm(2)). Hybridization of the modified targets where the non-native nucleobase was incorporated by solid-phase synthesis produced electrocatalytic signals from strands that were independently detected using radiolabeling and chronocoulometry. This result was used as a basis to develop an on-electrode amplification scheme where Taq polymerase was used to extend the immobilized DNA probes from solution-phase polymeric templates using modified nucleotriphosphates. This reaction produced an electrode that was modified with extended DNA containing the appropriate modified nucleotide. Radiolabeled nucleotide triphosphates were used to confirm the desired on-electrode DNA synthesis. When these electrodes were cycled in the presence of Os(bpy)(3)(2+), electrocatalytic signals were observed when as little as 40 amol (400 fM) of the desired target was present in the hybridization solution.
- Published
- 2003
- Full Text
- View/download PDF
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