25 results on '"Sampson, John H"'
Search Results
2. Bone marrow-derived dendritic cells pulsed with tumor homogenate induce immunity against syngeneic intracerebral glioma
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Heimberger, Amy B, Crotty, Laura E, Archer, Gary E, McLendon, Roger E, Friedman, Allan, Dranoff, Glenn, Bigner, Darell D, and Sampson, John H
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- 2000
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3. Hyaluronic acid based low viscosity hydrogel as a novel carrier for Convection Enhanced Delivery of CAR T cells.
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Atik, Ahmet F., Suryadevara, Carter M., Schweller, Ryan M., West, Jennifer L., Healy, Patrick, Herndon II, James E., Congdon, Kendra L., Sanchez-Perez, Luis, McLendon, Roger E., Archer, Gerald E., Fecci, Peter, and Sampson, John H.
- Abstract
Highlights • Obstacles for CED of CAR T cells are sedimentation, tube clogging, low viability. • LV Hydrogel is a biodegradable hyaluronic acid based biomaterial. • LV Hydrogel provides 20-fold increase in the delivery rate of CAR T cells. • Migration capacity and cytotoxicity of CAR T cells remain the same after infusion. • LV hydrogel has no toxic effect on rodent brain and fully disintegrated after 2 weeks. Abstract Convection Enhanced Delivery (CED) infuses therapeutic agents directly into the intracranial area continuously under pressure. The convection improves the distribution of therapeutics such as those aimed at brain tumors. Although CED successfully delivers small therapeutic agents, this technique fails to effectively deliver cells largely due to cell sedimentation during delivery. To overcome this limitation, we have developed a low viscosity hydrogel (LVHydrogel), which is capable of retaining cells in suspension. In this study, we evaluated whether LVHydrogel can effectively act as a carrier for the CED of tumor-specific chimeric antigen receptor (CAR) T cells. CAR T cells were resuspended in saline or LVHydrogel carriers, loaded into syringes, and passed through the CED system for 5 h. CAR T cells submitted to CED were counted and the efficiency of delivery was determined. In addition to delivery, the ability of CAR T cells to migrate and induce cytotoxicity was evaluated. Our studies demonstrate that LVHydrogel is a superior carrier for CED in comparison to saline. The efficiency of cell delivery in saline carrier was only ∼3–5% of the total cells whereas delivery by the LVHydrogel carrier was much higher, reaching ∼45–75%. Migration and Cytotoxicity was similar in both carriers in non-infused samples but we found superior cytotoxicity in LVHydrogel group post-infusion. We demonstrate that LVHydrogel, a biodegradable biomaterial which does not cause acute toxicity on preclinical animal models, prevents cellular sedimentation during CED and presents itself as a superior carrier to the current carrier, saline, for the CED of CAR T cells. [ABSTRACT FROM AUTHOR]
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- 2018
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4. Recurrent Malignant Gliomas.
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Kirkpatrick, John P. and Sampson, John H.
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In almost all patients, malignant glioma recurs following initial treatment with maximal safe resection, conformal radiotherapy, and temozolomide. This review describes the many options for treatment of recurrent malignant gliomas, including reoperation, alternating electric field therapy, chemotherapy, stereotactic radiotherapy or radiosurgery, or some combination of these modalities, presenting the evidence for each approach. No standard of care has been established, though the antiangiogenic agent, bevacizumab; stereotactic radiotherapy or radiosurgery; and, perhaps, combined treatment with these 2 modalities appear to offer modest benefits over other approaches. Clearly, randomized trials of these options would be advantageous, and novel, more efficacious approaches are urgently needed. [ABSTRACT FROM AUTHOR]
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- 2014
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5. Complete response to steroids in dural inflammatory pseudotumor associated with Still’s disease.
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Batich, Kristen A., William St. Clair, E., McLendon, Roger E., and Sampson, John H.
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Abstract: We report a unique case of a dural-based inflammatory pseudotumor (IPT) arising in the left cavernous sinus of a patient with a history of juvenile Still’s disease. The patient presented with hemi-facial paresthesias, dull, constant headaches, and transient episodes of sharp pain along the temporalis region. Treatment with oral steroid therapy resulted in complete regression of the lesion and accompanied neuralgia symptoms. Because intracranial IPT can mimic meningiomas both clinically and radiographically and can be associated with systemic arthritic diseases, neurosurgeons should be familiar with this entity in order to avoid unnecessary radical surgery and alternatively consider a tapering course of steroid therapy. [Copyright &y& Elsevier]
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- 2013
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6. Therapeutic approaches for HER2-positive brain metastases: circumventing the blood-brain barrier.
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Mehta, Ankit I, Brufsky, Adam M, and Sampson, John H
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We aim to summarize data from studies of trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) and brain metastasis and to describe novel methods being developed to circumvent the blood-brain barrier (BBB). A literature search was conducted to obtain data on the clinical efficacy of trastuzumab and lapatinib in patients with HER2-positive MBC and brain metastasis, as well as the transport of therapeutic molecules across the BBB. Trastuzumab-based therapy is the standard of care for patients with HER2-positive MBC. Post hoc and retrospective analyses show that trastuzumab significantly prolongs overall survival when given after the diagnosis of central nervous system (CNS) metastasis; this is probably attributable to its control of extracranial disease, although trastuzumab may have a direct effect on CNS disease in patients with local or general perturbation of the BBB. In patients without a compromised BBB, trastuzumab is thought to have limited access to the brain, because of its relatively large molecular size. Several approaches are being developed to enhance the delivery of therapeutic agents to the brain. These include physical or pharmacologic disruption of the BBB, direct intracerebral drug delivery, drug manipulation, and coupling drugs to transport vectors. Available data suggest that trastuzumab extends survival in patients with HER2-positive MBC and brain metastasis. Novel methods for delivery of therapeutic agents into the brain could be used in the future to enhance access to the CNS by trastuzumab, thereby improving its efficacy in this setting. [ABSTRACT FROM AUTHOR]
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- 2013
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7. Toward Effective Immunotherapy for the Treatment of Malignant Brain Tumors
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Mitchell, Duane A. and Sampson, John H.
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IMMUNOTHERAPY ,BRAIN tumor treatment ,TREATMENT effectiveness ,CANCER vaccines ,DENDRITIC cells ,IMMUNOSUPPRESSIVE agents ,GLIOMA treatment ,VACCINES ,T cells ,ANIMAL experimentation ,BRAIN tumors ,CELL physiology ,EPIDERMAL growth factor ,GLIOMAS ,IMMUNIZATION ,INTERLEUKIN-2 ,RESEARCH funding ,LYMPHOPENIA ,PHYSIOLOGY - Abstract
Summary: The immunologic treatment of cancer has long been heralded as a targeted molecular therapeutic with the promise of eradicating tumor cells with minimal damage to surrounding normal tissues. However, a demonstrative example of the efficacy of immunotherapy in modulating cancer progression is still lacking for most human cancers. Recent breakthroughs in our understanding of the mechanisms leading to full T-cell activation, and recognition of the importance of overcoming tumor-induced immunosuppressive mechanisms, have shed new light on how to generate effective anti-tumor immune responses in humans, and sparked a renewed and enthusiastic effort to realize the full potential of cancer immunotherapy. The immunologic treatment of invasive malignant brain tumors has not escaped this re-invigorated endeavor, and promising therapies are currently under active investigation in dozens of clinical trials at several institutions worldwide. This review will focus on some of the most important breakthroughs in our understanding of how to generate potent anti-tumor immune responses, and some of the clear challenges that lie ahead in achieving effective immunotherapy for the majority of patients with malignant brain tumors. A review of immunotherapeutic strategies currently under clinical evaluation, as well as an outline of promising novel approaches on the horizon, is included to provide perspective on the active and stalwart progress toward effective immunotherapy for the treatment of malignant brain tumors. [Copyright &y& Elsevier]
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- 2009
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8. Enhanced Oncolytic Virotherapy Through Oxidative Stress Inhibition.
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Congdon, Kendra L and Sampson, John H
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GENE therapy , *ONCOLOGY , *OXIDATIVE stress , *CANCER , *GLIOBLASTOMA multiforme - Abstract
The article offers information on oncolytic virotherapy (OV) using an oxidative stress inhibition. It informs that OV is the manipulation of replication-competent virus to selectively infect and lyse malignant cells while leaving normal cells untouched. OV represents a novel, tumor-targeted therapy for a variety of cancers intractable to current multimodality standards of care. Glioblastoma (GBM), the most aggressive of brain tumors.
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- 2013
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9. Utility of Routine Preoperative Urinalysis in the Prevention of Surgical Site Infections.
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Haskell-Mendoza, Aden P., Radhakrishnan, Senthil, Nardin, Ana Lisa, Eilbacher, Kristina, Yang, Lexie Zidanyue, Jackson, Joshua D., Lee, Hui-Jie, Sampson, John H., and Fecci, Peter E.
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SURGICAL site infections , *URINARY tract infections , *URINALYSIS , *CONFIDENCE intervals , *WOUND infections , *STEREOTAXIC techniques - Abstract
Preoperative assessment is important for neurosurgical risk stratification, but the level of evidence for individual screening tests is low. In preoperative urinalysis (UA), testing may significantly increase costs and lead to inappropriate antibiotic treatment. We prospectively evaluated whether eliminating preoperative UA was noninferior to routine preoperative UA as measured by 30-day readmission for surgical site infection in adult elective neurosurgical procedures. A single-institution prospective, pragmatic study of patients receiving elective neurosurgical procedures from 2018 to 2020 was conducted. Patients were allocated based on same-day versus preoperative admission status. Rates of preoperative UA and subsequent wound infection were measured along with detailed demographic, surgical, and laboratory data. The study included 879 patients. The most common types of surgery were cranial (54.7%), spine (17.4%), and stereotactic/functional (19.5%). No preoperative UA was performed in 315 patients, while 564 underwent UA. Of tested patients, 103 (18.3%) met criteria for suspected urinary tract infection, and 69 (12.2%) received subsequent antibiotic treatment. There were 14 patients readmitted within 30 days (7 without UA [2.2%] vs. 7 with UA [1.2%]) for subsequent wound infection with a risk difference of 0.98% (95% confidence interval −0.89% to 2.85%). The upper limit of the confidence interval exceeded the preselected noninferiority margin of 1%. In this prospective study of preoperative UA for elective neurosurgical procedures using a pragmatic, real-world design, risk of readmission due to surgical site infection was very low across the study cohort, suggesting a limited role of preoperative UA for elective neurosurgical procedures. [ABSTRACT FROM AUTHOR]
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- 2023
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10. Intracerebral delivery of a third generation EGFRvIII-specific chimeric antigen receptor is efficacious against human glioma.
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Choi, Bryan D., Suryadevara, Carter M., Gedeon, Patrick C., Herndon II, James E., Sanchez-Perez, Luis, Bigner, Darell D., and Sampson, John H.
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Abstract: Chimeric antigen receptors (CAR)-transduced T cells hold great promise in the treatment of malignant disease. Here, we demonstrate that intracerebral injection with a human, epidermal growth factor receptor variant III (EGFRvIII)-specific, third generation CAR successfully treats glioma in mice. Importantly, these results endorse clinical translation of this CAR in patients with EGFRvIII-expressing brain tumors. [Copyright &y& Elsevier]
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- 2014
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11. The limitations of imaging response criteria
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Mehta, V Ankit I and Sampson, John H
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- 2012
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12. Effective effectors: How T cells access and infiltrate the central nervous system.
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Congdon, Kendra L., Sanchez-Perez, Luis A., and Sampson, John H.
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VACCINE effectiveness , *CENTRAL nervous system , *T cells , *CENTRAL nervous system diseases , *BRAIN tumors ,CENTRAL nervous system tumors - Abstract
Several Phase II and III clinical trials have demonstrated that immunotherapy can induce objective responses in otherwise refractory malignancies in tumors outside the central nervous system. In large part, effector T cells mediate much of the antitumor efficacy in these trials, and potent antitumor T cells can be generated through vaccination, immune checkpoint blockade, adoptive transfer, and genetic manipulation. However, activated T cells must still traffic to, infiltrate, and persist within tumor in order to mediate tumor lysis. These requirements for efficacy pose unique challenges for brain tumor immunotherapy, due to specific anatomical barriers and populations of specialized immune cells within the central nervous system that function to constrain immunity. Both autoimmune and infectious diseases of the central nervous system provide a wealth of information on how T cells can successfully migrate to the central nervous system and then engender sustained immune responses. In this review, we will examine the commonalities in the efferent arm of immunity to the brain for autoimmunity, infection, and tumor immunotherapy to identify key factors underlying potent immune responses. [ABSTRACT FROM AUTHOR]
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- 2019
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13. Accuracy of Novel Computed Tomography–Guided Frameless Stereotactic Drilling and Catheter System in Human Cadavers.
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Sankey, Eric W., Butler, Eric, and Sampson, John H.
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STEREOTAXIC techniques , *CATHETERS , *MEDICAL cadavers , *BRAIN tomography , *INTRAOPERATIVE care - Abstract
Objective To evaluate accuracy of a computed tomography (CT)–guided frameless stereotactic drilling and catheter system. Methods A prospective, single-arm study was performed using human cadaver heads to evaluate placement accuracy of a novel, flexible intracranial catheter and stabilizing bone anchor system and drill kit. There were 20 catheter placements included in the analysis. The primary endpoint was accuracy of catheter tip location on intraoperative CT. Secondary endpoints included target registration error and entry and target point error before and after drilling. Measurements are reported as mean ± SD (median, range). Results Target registration error was 0.46 mm ± 0.26 (0.50 mm, −1.00 to 1.00 mm). Two (10%) target point trajectories were negatively impacted by drilling. Intracranial catheter depth was 59.8 mm ± 9.4 (60.5 mm, 38.0–80.0 mm). Drilling angle was 22° ± 9 (21°, 7°–45°). Deviation between planned and actual entry point on CT was 1.04 mm ± 0.38 (1.00 mm, 0.40–2.00 mm). Deviation between planned and actual target point on CT was 1.60 mm ± 0.98 (1.40 mm, 0.40–4.00 mm). No correlation was observed between intracranial catheter depth and target point deviation (accuracy) (Pearson coefficient 0.018) or between technician experience and accuracy (Pearson coefficient 0.020). There was no significant difference in accuracy with trajectories performed for different cadaver heads ( P = 0.362). Conclusions Highly accurate catheter placement is achievable using this novel flexible catheter and bone anchor system placed via frameless stereotaxy, with an average deviation between planned and actual target point of 1.60 mm ± 0.98 (1.40 mm, 0.40–4.00 mm). [ABSTRACT FROM AUTHOR]
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- 2017
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14. Local production of TGF β1 inhibits cerebral edema, enhances TNF- α induced apoptosis and improves survival in a murine glioma model
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Ashley, David M, Sampson, John H, Archer, Gary E, Hale, Laura P, and Bigner, Darell D
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- 1998
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15. A genetically modified allogeneic cellular vaccine generates MHC class I-restricted cytotoxic responses against tumor-associated antigens and protects against CNS tumors in vivo
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Ashley, David M, Sampson, John H, Archer, Gary E, Batra, Surinder K, Bigner, Darell D, and Hale, Laura P
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- 1997
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16. Defining the Optimal Planning Target Volume in Image-Guided Stereotactic Radiosurgery of Brain Metastases: Results of a Randomized Trial.
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Kirkpatrick, John P., Wang, Zhiheng, Sampson, John H., McSherry, Frances, IIHerndon, James E., Allen, Karen J., Duffy, Eileen, Hoang, Jenny K., Chang, Zheng, Yoo, David S., Kelsey, Chris R., and Yin, Fang-Fang
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STEREOTACTIC radiosurgery , *BRAIN metastasis , *RANDOMIZED controlled trials , *KARNOFSKY Performance Status , *COGNITION , *FOLLOW-up studies (Medicine) - Abstract
Purpose To identify an optimal margin about the gross target volume (GTV) for stereotactic radiosurgery (SRS) of brain metastases, minimizing toxicity and local recurrence. Methods and Materials Adult patients with 1 to 3 brain metastases less than 4 cm in greatest dimension, no previous brain radiation therapy, and Karnofsky performance status (KPS) above 70 were eligible for this institutional review board–approved trial. Individual lesions were randomized to 1- or 3- mm uniform expansion of the GTV defined on contrast-enhanced magnetic resonance imaging (MRI). The resulting planning target volume (PTV) was treated to 24, 18, or 15 Gy marginal dose for maximum PTV diameters less than 2, 2 to 2.9, and 3 to 3.9 cm, respectively, using a linear accelerator–based image-guided system. The primary endpoint was local recurrence (LR). Secondary endpoints included neurocognition Mini-Mental State Examination, Trail Making Test Parts A and B, quality of life (Functional Assessment of Cancer Therapy-Brain), radionecrosis (RN), need for salvage radiation therapy, distant failure (DF) in the brain, and overall survival (OS). Results Between February 2010 and November 2012, 49 patients with 80 brain metastases were treated. The median age was 61 years, the median KPS was 90, and the predominant histologies were non–small cell lung cancer (25 patients) and melanoma (8). Fifty-five, 19, and 6 lesions were treated to 24, 18, and 15 Gy, respectively. The PTV/GTV ratio, volume receiving 12 Gy or more, and minimum dose to PTV were significantly higher in the 3-mm group (all P <.01), and GTV was similar ( P =.76). At a median follow-up time of 32.2 months, 11 patients were alive, with median OS 10.6 months. LR was observed in only 3 lesions (2 in the 1 mm group, P =.51), with 6.7% LR 12 months after SRS. Biopsy-proven RN alone was observed in 6 lesions (5 in the 3-mm group, P =.10). The 12-month DF rate was 45.7%. Three months after SRS, no significant change in neurocognition or quality of life was observed. Conclusions SRS was well tolerated, with low rates of LR and RN in both cohorts. However, given the higher potential risk of RN with a 3-mm margin, a 1-mm GTV expansion is more appropriate. [ABSTRACT FROM AUTHOR]
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- 2015
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17. Safety and Efficacy of Stereotactic Radiosurgery and Adjuvant Bevacizumab in Patients With Recurrent Malignant Gliomas
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Cuneo, Kyle C., Vredenburgh, James J., Sampson, John H., Reardon, David A., Desjardins, Annick, Peters, Katherine B., Friedman, Henry S., Willett, Christopher G., and Kirkpatrick, John P.
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RADIOSURGERY , *STEREOTAXIC techniques , *ADJUVANT treatment of cancer , *BEVACIZUMAB , *GLIOMAS , *CANCER relapse , *DRUG efficacy , *MEDICATION safety - Abstract
Purpose: Patients with recurrent malignant gliomas treated with stereotactic radiosurgery (SRS) and multiagent systemic therapies were reviewed to determine the effects of patient- and treatment-related factors on survival and toxicity. Methods and Materials: A retrospective analysis was performed on patients with recurrent malignant gliomas treated with salvage SRS from September 2002 to March 2010. All patients had experienced progression after treatment with temozolomide and radiotherapy. Salvage SRS was typically administered only after multiple postchemoradiation salvage systemic therapies had failed. Results: 63 patients were treated with SRS for recurrent high-grade glioma; 49 patients had World Health Organization (WHO) Grade 4 disease. Median follow-up was 31 months from primary diagnosis and 7 months from SRS. Median overall survival from primary diagnosis was 41 months for all patients. Median progression-free survival (PFS) and overall survival from SRS (OS-SRS) were 6 and 10 months for all patients, respectively. The 1-year OS-SRS for patients with Grade 4 glioma who received adjuvant (concurrent with or after SRS) bevacizumab was 50% vs. 22% for patients not receiving adjuvant bevacizumab (p = 0.005). Median PFS for patients with a WHO Grade 4 glioma who received adjuvant bevacizumab was 5.2 months vs. 2.1 months for patients who did not receive adjuvant bevacizumab (p = 0.014). Karnofsky performance status (KPS) and age were not significantly different between treatment groups. Treatment-related Grade 3/4 toxicity for patients receiving and not receiving adjuvant BVZ was 10% and 14%, respectively (p = 0.58).On multivariate analysis, the relative risk of death and progression with adjuvant bevacizumab was 0.37 (confidence interval [CI] 0.17–0.82) and 0.45 (CI 0.21–0.97). KPS >70 and age <50 years were significantly associated with improved survival. Conclusions: The combination of salvage radiosurgery and bevacizumab to treat recurrent malignant gliomas is well tolerated and seems to be associated with improved outcomes. Prospective multiinstitutional studies are required to determine efficacy and long-term toxicity with this approach. [ABSTRACT FROM AUTHOR]
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- 2012
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18. Stereotactic Body Radiotherapy for Lesions of the Spine and Paraspinal Regions
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Nelson, John W., Yoo, David S., Sampson, John H., Isaacs, Robert E., Larrier, Nicole A., Marks, Lawrence B., Yin, Fang-Fang, Wu, Q. Jackie, Wang, Zhiheng, and Kirkpatrick, John P.
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STEREOTAXIC techniques , *CANCER radiotherapy , *SPINAL tumors , *TOMOGRAPHY , *SIMULATION methods & models , *RADIATION doses - Abstract
Purpose: To describe our experience and clinical strategy for stereotactic body radiotherapy (SBRT) of spinal lesions. Methods and Materials: Thirty-two patients with 33 spinal lesions underwent computed tomography–based simulation while free breathing. Gross/clinical target volumes included involved portions of the vertebral body and paravertebral/epidural tumor. Planning target volume (PTV) expansion was 6 mm axially and 3 mm radially; the cord was excluded from the PTV. Biologic equivalent dose was calculated using the linear quadratic model with α/β = 3 Gy. Treatment was linear accelerator based with on-board imaging; dose was adjusted to maintain cord dose within tolerance. Survival, local control, pain, and neurologic status were monitored. Results: Twenty-one patients are alive at 1 year (median survival, 14 months). Median follow-up is 6 months for all patients (7 months for survivors). Mean previous radiotherapy dose to 22 patients was 35 Gy, and median interval was 17 months. Renal (31%), breast, and lung (19% each) were the most common histologic sites. Three SBRT fractions (range, one to four fractions) of 7 Gy (range, 5–16 Gy) were delivered. Median cord and target biologic equivalent doses were 70 Gy3 and 34.3 Gy10, respectively. Thirteen patients reported complete and 17 patients reported partial pain relief at 1 month. There were four failures (mean, 5.8 months) with magnetic resonance imaging evidence of in-field progression. No dosimetric parameters predictive of failure were identified. No treatment-related toxicity was seen. Conclusions: Spinal SBRT is effective in the palliative/re-treatment setting. Volume expansion must ensure optimal PTV coverage while avoiding spinal cord toxicity. The long-term safety of spinal SBRT and the applicability of the linear-quadratic model in this setting remain to be determined, particularly the time-adjusted impact of prior radiotherapy. [Copyright &y& Elsevier]
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- 2009
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19. A simple and enzyme-free method for processing infiltrating lymphocytes from small mouse tumors for ELISpot analysis.
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Swartz, Adam M., Reap, Elizabeth, Norberg, Pamela, Schmittling, Robert, Janetzki, Sylvia, Sanchez-Perez, Luis, and Sampson, John H.
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ENZYMES , *LYMPHOCYTES , *BRAIN tumors , *ENZYME-linked immunosorbent assay , *IMMUNE response , *ANTIGEN analysis - Abstract
The ELISpot assay prevails as one of the most sensitive and meaningful assays for the detection of antigen-specific, effector immune responses. Acquisition of cellular analyte for ELISpot analysis is typically not problematic when derived from tissues enriched in lymphocytes (e.g., lymphoid organs and blood); however, cell processing becomes more difficult when lymphocytes represent only a very minor population relative to the source tissue, especially when the source tissue is in limited supply (e.g., small mouse tumors). Traditional enzymatic-based methods for dissociating tumors often result in poor yields, inconsistent lymphocyte enrichment, and can have deleterious effects on lymphocyte phenotype and function. To address these limitations, we have developed an enzyme-free protocol for processing tumor infiltrating lymphocytes (TILs) from small mouse tumors, which enables the enumeration of antigen-specific effector lymphocytes using ELISpot analysis. This procedure is predicated on the dissociation of tumor tissue using gentle agitation with a paddle blender followed by a brief in vitro culture period to remove adherent cells, as well as to revive lymphocytes from a non-responsive state. Although this method is demonstrated with mouse intracerebral tumors, we have found that this protocol is applicable to peripheral tumors and may likely extend to alternative tissue sources wherein lymphocytes exist in low numbers. [ABSTRACT FROM AUTHOR]
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- 2018
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20. Rational design and generation of recombinant control reagents for bispecific antibodies through CDR mutagenesis.
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Choi, Bryan D., Gedeon, Patrick C., Kuan, Chien-Tsun, Sanchez-Perez, Luis, Archer, Gary E., Bigner, Darell D., and Sampson, John H.
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MUTAGENESIS , *BISPECIFIC antibodies , *RECOMBINANT antibodies , *CANCER treatment , *EPIDERMAL growth factor receptors , *MEDICAL sciences , *TUMOR antigens , *LIGANDS (Biochemistry) , *CD3 antigen - Abstract
Abstract: Developments in the field of bispecific antibodies have progressed rapidly in recent years, particularly in their potential role for the treatment of malignant disease. However, manufacturing stable molecules has proven to be costly and time-consuming, which in turn has hampered certain aspects of preclinical evaluation including the unavailability of appropriate “negative” controls. Bispecific molecules (e.g., bispecific tandem scFv) exhibit two specificities, often against a tumor antigen as well as an immune-activation ligand such as CD3. While for IgG antibodies, isotype-matched controls are well accepted, when considering smaller antibody fragments it is not possible to adequately control for their biological activity through the use of archetypal isotypes, which differ dramatically in affinity, size, structure, and design. Here, we demonstrate a method for the rapid production of negative control tandem scFvs through complementarity determining region (CDR) mutagenesis, using a recently described bispecific T-cell engager (BiTE) targeting a tumor-specific mutation of the epidermal growth factor receptor (EGFRvIII) as an example. Four independent control constructs were developed by this method through alteration of residues spanning individual CDR domains. Importantly, while target antigen affinity was completely impaired, CD3 binding affinity was conserved in each molecule. These results have a potential to enhance the sophistication by which bispecific antibodies can be evaluated in the preclinical setting and may have broader applications for an array of alternative antibody-derived therapeutic platforms. [Copyright &y& Elsevier]
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- 2013
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21. Concurrent Stereotactic Radiosurgery and Bevacizumab in Recurrent Malignant Gliomas: A Prospective Trial.
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Cabrera, Alvin R., Cuneo, Kyle C., Desjardins, Annick, Sampson, John H., McSherry, Frances, Herndon, James E., Peters, Katherine B., Allen, Karen, Hoang, Jenny K., Chang, Zheng, Craciunescu, Oana, Vredenburgh, James J., Friedman, Henry S., and Kirkpatrick, John P.
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STEREOTACTIC radiosurgery , *BEVACIZUMAB , *GLIOMA treatment , *CLINICAL trials , *ADJUVANT treatment of cancer , *QUALITY of life - Abstract
Purpose: Virtually all patients with malignant glioma (MG) eventually recur. This study evaluates the safety of concurrent stereotactic radiosurgery (SRS) and bevacizumab (BVZ), an antiangiogenic agent, in treatment of recurrent MG. Methods and Materials: Fifteen patients with recurrent MG, treated at initial diagnosis with surgery and adjuvant radiation therapy/temozolomide and then at least 1 salvage chemotherapy regimen, were enrolled in this prospective trial. Lesions <3 cm in diameter were treated in a single fraction, whereas those 3 to 5 cm in diameter received 5 5-Gy fractions. BVZ was administered immediately before SRS and 2 weeks later. Neurocognitive testing (Mini-Mental Status Exam, Trail Making Test A/B), Functional Assessment of Cancer Therapy-Brain (FACT-Br) quality-of-life assessment, physical exam, and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) were performed immediately before SRS and 1 week and 2 months following completion of SRS. The primary endpoint was central nervous system (CNS) toxicity. Secondary endpoints included survival, quality of life, microvascular properties as measured by DCE-MRI, steroid usage, and performance status. Results: One grade 3 (severe headache) and 2 grade 2 CNS toxicities were observed. No patients experienced grade 4 to 5 toxicity or intracranial hemorrhage. Neurocognition, quality of life, and Karnofsky performance status did not change significantly with treatment. DCE-MRI results suggest a significant decline in tumor perfusion and permeability 1 week after SRS and further decline by 2 months. Conclusions: Treatment of recurrent MG with concurrent SRS and BVZ was not associated with excessive toxicity in this prospective trial. A randomized trial of concurrent SRS/BVZ versus conventional salvage therapy is needed to establish the efficacy of this approach. [Copyright &y& Elsevier]
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- 2013
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22. A comprehensive outlook on intracerebral therapy of malignant gliomas
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Buonerba, Carlo, Di Lorenzo, Giuseppe, Marinelli, Alfredo, Federico, Piera, Palmieri, Giovannella, Imbimbo, Martina, Conti, Pio, Peluso, Gianfranco, De Placido, Sabino, and Sampson, John H.
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GLIOBLASTOMA multiforme treatment , *CANCER chemotherapy , *CANCER radiotherapy , *ONCOLOGIC surgery , *DRUG administration , *BLOOD-brain barrier , *MEDICAL research , *DRUG delivery systems - Abstract
Abstract: Glioblastoma multiforme (GBM) is the most frequent and aggressive malignant glioma (MG), with a median survival time of 12–15 months, despite current best treatment based on surgery, radiotherapy and systemic chemotherapy. Many potentially active therapeutic agents are not effective by systemic administration, because they are unable to cross the blood–brain barrier (BBB). As intracerebral administration bypasses the BBB, it increases the number of drugs that can be successfully delivered to the brain, with the possibility of minor systemic toxicity and better effectiveness. This review summarizes the results of the extensive clinical research conducted on intracerebral therapy. Biodegradable drug carriers, implantable subcutaneous reservoirs and convection-enhanced delivery (CED) represent the main techniques for intracerebral delivery, while conventional chemotherapy agents, radiolabeled antibodies and receptor-targeted toxins are the main classes of drugs for intracerebral therapy. At the present time, biodegradable carmustine wafers, commercialized as Gliadel®, are the only FDA-approved treatment for intracerebral chemotherapy of MG, but intracavitary delivery of mitoxantrone and radiolabeled antitenascin antibodies via implantable reservoirs has yielded promising results in uncontrolled trials. The pressure-driven flow generated by CED can potentially distribute convected drugs over large volumes of the brain, independently on their intrinsic diffusivity. Nevertheless, prominent technical problems, like backflow, are yet to be properly addressed and contributed to the disappointing results of two phase III trials that investigated CED of cintredekin besudotox and TransMid™ in patients with recurrent GBM. [Copyright &y& Elsevier]
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- 2011
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23. Treatment of HER2-positive breast carcinomatous meningitis with intrathecal administration of α-particle-emitting 211At-labeled trastuzumab
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Boskovitz, Abraham, McLendon, Roger E., Okamura, Tatsunori, Sampson, John H., Bigner, Darell D., and Zalutsky, Michael R.
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BREAST cancer treatment , *CANCER radioimmunotherapy , *CANCER radiotherapy , *TRASTUZUMAB , *RADIOLABELING , *ASTATINE , *TARGETED drug delivery , *MONOCLONAL antibodies , *RADIOISOTOPE therapy - Abstract
Abstract: Introduction: Carcinomatous meningitis (CM) is a devastating disease characterized by the dissemination of malignant tumor cells into the subarachnoid space along the brain and spine. Systemic treatment with monoclonal antibody (mAb) trastuzumab can be effective against HER2-positive systemic breast carcinoma but, like other therapies, is ineffective against CM. The goal of this study was to evaluate the therapeutic effect of α-particle emitting 211At-labeled trastuzumab following intrathecal administration in a rat model of breast carcinoma CM. Methods: Athymic rats were injected intrathecally with MCF-7/HER2-18 breast carcinoma cells through a surgically implanted indwelling intrathecal catheter. In Experiment 1, animals received 33 or 66 μCi 211At-labeled trastuzumab, cold trastuzumab or saline. In Experiment 2, animals were inoculated with a lower tumor burden and received 46 or 92 μCi 211At-labeled trastuzumab or saline. In Experiment 3, animals received 28 μCi 211At-labeled trastuzumab, 30 μCi 211At-labeled TPS3.2 control mAb or saline. Histopathological analysis of the neuroaxis was performed at the end of the study. Results: In Experiment 1, median survival increased from 21 days for the saline and cold trastuzumab groups to 45 and 48 days for 33 and 66 μCi 211At-labeled trastuzumab, respectively. In Experiment 2, median survival increased from 23 days for saline controls to 68 and 92 days for 46 and 92 μCi 211At-labeled trastuzumab, respectively. In Experiment 3, median survival increased from 20 days to 29 and 36 days for animals treated with 211At-labeled TPS3.2 and 211At-labeled trastuzumab, respectively. Long-term survivors were observed exclusively in the 211At-trastuzumab-treated groups. Conclusion: Intrathecal 211At-labeled trastuzumab shows promise as a treatment for patients with HER2-positive breast CM. [Copyright &y& Elsevier]
- Published
- 2009
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24. Detection of humoral response in patients with glioblastoma receiving EGFRvIII-KLH vaccines
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Schmittling, Robert J., Archer, Gary E., Mitchell, Duane A., Heimberger, Amy, Pegram, Charles, Herndon, James E., Friedman, Henry S., Bigner, Darell D., and Sampson, John H.
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GLIOBLASTOMA multiforme , *TUMORS , *IMMUNOTHERAPY , *VACCINES - Abstract
Abstract: The epidermal growth factor receptor variant III (EGFRvIII) is a consistent tumor-specific mutation that is widely expressed in glioblastoma multiforme (GBM) and other neoplasms. As such it represents a truly tumor-specific target for antitumor immunotherapy. Although endogenous humoral responses to EGFRvIII have been reported in patients with EGFRvIII-expressing breast cancer, it is not known whether de novo responses can be generated or endogenous responses enhanced with an EGFRvIII-specific vaccine. To assess this in clinical trials, we have developed and validated an immunoassay to measure and isolate anti-EGFRvIII and anti-KLH antibodies from the serum of patients vaccinated with an EGFRvIII-specific peptide (PEPvIII) conjugated to keyhole limpet hemocyanin (KLH). Using magnetic beads with immobilized antigen we captured and detected anti-EGFRvIII and anti-KLH antibodies in serum from patients before and after vaccinations. Using this assay, we found that significant levels of antibody for tumor-specific antigen EGFRvIII (>4 µg/mL) and KLH could be induced after vaccination with PEPvIII-KLH. [Copyright &y& Elsevier]
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- 2008
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25. Immunotherapy response assessment in neuro-oncology: a report of the RANO working group.
- Author
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Okada, Hideho, Weller, Michael, Huang, Raymond, Finocchiaro, Gaetano, Gilbert, Mark R, Wick, Wolfgang, Ellingson, Benjamin M, Hashimoto, Naoya, Pollack, Ian F, Brandes, Alba A, Franceschi, Enrico, Herold-Mende, Christel, Nayak, Lakshmi, Panigrahy, Ashok, Pope, Whitney B, Prins, Robert, Sampson, John H, Wen, Patrick Y, and Reardon, David A
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IMMUNOTHERAPY , *INFLAMMATION , *CANCER invasiveness , *IMMUNE response , *FOLLOW-up studies (Medicine) , *ADRENOCORTICAL hormones , *ALGORITHMS , *NERVOUS system tumors , *MEDICAL protocols , *RESEARCH funding , *DISEASE progression , *DIAGNOSIS , *TUMOR treatment - Abstract
Immunotherapy is a promising area of therapy in patients with neuro-oncological malignancies. However, early-phase studies show unique challenges associated with the assessment of radiological changes in response to immunotherapy reflecting delayed responses or therapy-induced inflammation. Clinical benefit, including long-term survival and tumour regression, can still occur after initial disease progression or after the appearance of new lesions. Refinement of the response assessment criteria for patients with neuro-oncological malignancies undergoing immunotherapy is therefore warranted. Herein, a multinational and multidisciplinary panel of neuro-oncology immunotherapy experts describe immunotherapy Response Assessment for Neuro-Oncology (iRANO) criteria based on guidance for the determination of tumour progression outlined by the immune-related response criteria and the RANO working group. Among patients who demonstrate imaging findings meeting RANO criteria for progressive disease within 6 months of initiating immunotherapy, including the development of new lesions, confirmation of radiographic progression on follow-up imaging is recommended provided that the patient is not significantly worse clinically. The proposed criteria also include guidelines for the use of corticosteroids. We review the role of advanced imaging techniques and the role of measurement of clinical benefit endpoints including neurological and immunological functions. The iRANO guidelines put forth in this Review will evolve successively to improve their usefulness as further experience from immunotherapy trials in neuro-oncology accumulate. [ABSTRACT FROM AUTHOR]
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- 2015
- Full Text
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