41 results on '"Young Hyun Cho"'
Search Results
2. Impact of clinicopathologic features on leptomeningeal metastasis from lung adenocarcinoma and treatment efficacy with epidermal growth factor receptor tyrosine kinase inhibitor
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Young Hyun Cho, Chang-Min Choi, Shin Kyo Yoon, Byoung Soo Kwon, Do Hoon Kwon, Sang We Kim, Jae Cheol Lee, and Dae Ho Lee
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Male ,0301 basic medicine ,Oncology ,Lung Neoplasms ,medicine.medical_treatment ,Metastasis ,0302 clinical medicine ,Interquartile range ,Carcinoma, Non-Small-Cell Lung ,Neoplasm Metastasis ,EGFR‐TKI ,Hazard ratio ,General Medicine ,Middle Aged ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,ErbB Receptors ,Survival Rate ,Treatment Outcome ,030220 oncology & carcinogenesis ,Adenocarcinoma ,Female ,Original Article ,Meningeal Carcinomatosis ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Adenocarcinoma of Lung ,lcsh:RC254-282 ,03 medical and health sciences ,leptomeningeal metastasis ,Internal medicine ,Biomarkers, Tumor ,medicine ,Ommaya reservoir ,Humans ,Lung cancer ,Protein Kinase Inhibitors ,Aged ,Retrospective Studies ,Chemotherapy ,Performance status ,business.industry ,intrathecal (IT) ,Original Articles ,medicine.disease ,lung cancer ,030104 developmental biology ,Mutation ,business ,Follow-Up Studies - Abstract
Background We investigated the risk factors for leptomeningeal carcinomatosis (LMC) and compared clinical efficacies of various treatment modalities including intrathecal (IT) chemotherapy in patients with lung adenocarcinoma harboring epidermal growth factor receptor (EGFR) mutations. Methods Using clinical research data from the Asan Medical Center, we retrospectively analyzed data of patients diagnosed with LMC, confirmed via cerebrospinal fluid (CSF) analysis from January 2008 to December 2017. Results We identified 1189 patients with lung adenocarcinoma harboring EGFR mutations. Among these, 9.8% had a median duration of 13.5 (interquartile range [IQR] 6.8–23.6) months from the initial lung cancer diagnosis to LMC occurrence. Younger age (hazard ratio [HR] 1.043, P
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- 2020
3. Thirty-year clinical experience in gamma knife radiosurgery for trigeminal schwannomas
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Dong-Won Shin, Chunseng Ju, Hyun Seok Lee, Hee Jun Yoo, Sang Woo Song, Young Hyun Cho, Chang-Ki Hong, Seok Ho Hong, Do Heui Lee, Jeong Hoon Kim, and Young-Hoon Kim
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Multidisciplinary ,Treatment Outcome ,Facial Pain ,Trigeminal Nerve Diseases ,Humans ,Cranial Nerve Neoplasms ,Radiosurgery ,Neurilemmoma ,Follow-Up Studies ,Retrospective Studies ,Tumor Burden - Abstract
We aimed to evaluate the radiographic and clinical outcomes after gamma knife radiosurgery (GKRS) for trigeminal schwannomas (TSs). A total of 87 patients who underwent GKRS for TSs between 1990 and 2020 were enrolled. The mean tumor volume was 4.3 cm3. The median prescribed dose for the margins of the tumor was 13 Gy. The median follow-up duration was 64.3 months (range 12.0–311.5 months). The overall local tumor control rate was 90%, and the symptom response rate was 93%. The response rate for each symptom was 88% for facial pain, 97% for facial sensory change, and 86% for cranial nerve deficits. Nineteen (22%) patients showed transient swelling, which had regressed at the time of the last follow-up. Cystic tumors were associated with transient swelling (p = 0.04). A tumor volume of 3 was associated with local tumor control in univariable analysis. Transient swelling was associated with symptom control failure in both univariable and multivariable analyses (p = 0.04, odds ratio 14.538). GKRS is an effective treatment for TSs, both for local control and symptom control.
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- 2022
4. Single- and hypofractionated stereotactic radiosurgery for large ( 2 cm) brain metastases: a systematic review
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Eun Jung, Lee, Kyu-Sun, Choi, Eun Suk, Park, and Young Hyun, Cho
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Treatment Outcome ,Brain Neoplasms ,Humans ,Radiosurgery - Abstract
Since frameless stereotactic radiosurgery (SRS) techniques have been recently introduced, hypofractionated SRS (HF-SRS) for large brain metastases (BMs) is gradually increasing. To verify the efficacy and safety of HF-SRS for large BMs, we aimed to perform a systematic review and compared them with SF-SRS.We systematically searched the studies regarding SF-SRS or HF-SRS for large ( 2 cm) BM from databases including PubMed, Embase, and the Cochrane Library on July 31, 2018. Biologically effective dose with the α/β ratio of 10 (BEDThe 15 studies with 1049 BMs that described 1-year LC and RN were included. HF-SRS tended to be performed in larger tumors; however, higher mean BEDHF-SRS results in better LC of large BMs while simultaneously reducing RN compared to SF-SRS. Thus, HF-SRS should be considered a priority for SF-SRS in patients with large BMs who are not suitable to undergo surgical resection.
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- 2021
5. Malignant Transformation of a Rosette-Forming Glioneuronal Tumor to Glioblastoma
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Jeong Hoon Kim, Chang Jin Kim, Young Hoon Kim, Young Hyun Cho, Joonho Byun, Seok Ho Hong, and Sae Min Kwon
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Male ,medicine.medical_specialty ,Rosette Formation ,Brain tumor ,Malignant transformation ,03 medical and health sciences ,0302 clinical medicine ,Glioneuronal tumor ,Cerebellar hemisphere ,medicine ,Humans ,Favorable outcome ,Fourth Ventricle ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Neoplasms, Neuroepithelial ,Gross Total Resection ,030220 oncology & carcinogenesis ,Surgery ,Neurology (clinical) ,Radiology ,Neoplasm Recurrence, Local ,Glioblastoma ,business ,Cerebral Ventricle Neoplasms ,030217 neurology & neurosurgery - Abstract
Background A rosette-forming glioneuronal tumor (RGNT), a rare brain tumor, presents as a benign feature with a favorable outcome. To date, a few cases with aggressive behaviors, such as recurrence or dissemination, but none with malignant transformation, have been reported. We describe 1 case that recurred as glioblastoma after complete resection of the benign RGNT. Case Description A man aged 58 years presented with headache and dizziness without neurologic symptoms. Magnetic resonance imaging showed a 4 × 2.5 cm, well-demarcated mass in the left cerebellar hemisphere. The patient underwent gross total resection of the tumor and a diagnosis of RGNT was made. There was no evidence of recurrence on serial follow-up. However, a recurrent heterogeneous enhancing mass in the previous surgical cavity was observed on a 7-year postoperative magnetic resonance imaging scan. Reoperation was performed and a histopathological study revealed a glioblastoma. Conclusions To the best of our knowledge, this is the first case of spontaneous malignant transformation of an RGNT. Our case may be helpful in better understanding the biological behavior and clinical outcome of RGNT. We emphasize the malignant potential of this rare tumor and the necessity of future large-scaled research for most appropriate therapeutic strategies.
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- 2019
6. Growth rate and fate of untreated hemangioblastomas: clinical assessment of the experience of a single institution
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Joonho Byun, Seok Ho Hong, Young Hyun Cho, Young Hoon Kim, Chang Jin Kim, Hee Jun Yoo, and Jeong Hoon Kim
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Adult ,Male ,Cancer Research ,medicine.medical_specialty ,von Hippel-Lindau Disease ,Adolescent ,Gastroenterology ,Wait and scan ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,Internal medicine ,Hemangioblastoma ,Outcome Assessment, Health Care ,medicine ,Humans ,Tumor growth ,Growth rate ,Single institution ,Cerebellar Neoplasms ,Child ,Aged ,Retrospective Studies ,business.industry ,Mean age ,Odds ratio ,Middle Aged ,medicine.disease ,Tumor Burden ,Survival Rate ,Natural history ,Neurology ,Oncology ,030220 oncology & carcinogenesis ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
The growth rate and natural history of untreated hemangioblastomas remain unclear. This study investigated the natural history of untreated intracranial hemangioblastomas and predictors of tumor growth using volumetric assessment. This study retrospectively enrolled 31 patients with untreated hemangioblastomas between 2004 and 2017 who were followed up for at least 12 months. The 31 patients had a total of 52 hemangioblastomas. The 31 patients included 11 (35.5%) men and 20 (64.5%) women, of mean age 42.5 years. Seventeen (54.8%) patients were genetically diagnosed with Von Hippel-Lindau (VHL) disease. Of the 52 lesions, 33 (63.5%) grew during the follow-up period, whereas 19 (36.5%) remained stable. Overall mean actual growth rate (AGR) was 1.94 cm3/year, 2.38 cm3/year in the VHL and 1.79 cm3/year in the non-VHL group (p = 0.31). Overall mean relative growth rate (RGR) was 21%/year, 26%/year in the VHL and 19%/year in the non-VHL group. Time to 50% treatment probability was 34 months. The 1, 3, 5, and 7-year treatment probabilities were 11.5%, 50.1%, 52.7%, and 73%, respectively. The presence of only symptomatic lesions was significantly predictive of the growth of intracranial hemangioblastoma (odds ratio: 5.0, p = 0.02). The overall growth rate of intracranial hemangioblastoma was faster than that of other benign intracranial tumors, with symptomatic lesions being the only meaningful predictor of tumor growth. Because of their rapid growth rate and high probability of treatment, a wait and scan management strategy should be carefully applied to intracranial hemangioblastomas.
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- 2019
7. Comparison of Survival Outcomes Between Partial Resection and Biopsy for Primary Glioblastoma: A Propensity Score-Matched Study
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Seok Ho Hong, Young Hyun Cho, Ho Sung Kim, Ji Eun Park, Jeong Hoon Kim, Joonho Byun, Sang Joon Kim, Young Hoon Kim, Soo Jung Nam, and Chang Jin Kim
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Adult ,Male ,medicine.medical_specialty ,Biopsy ,Gastroenterology ,Neurosurgical Procedures ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,In patient ,Propensity Score ,DNA Modification Methylases ,Aged ,Aged, 80 and over ,Primary Glioblastoma ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,Tumor Suppressor Proteins ,Hazard ratio ,DNA Methylation ,Middle Aged ,Partial resection ,medicine.disease ,Magnetic Resonance Imaging ,Gross Total Resection ,Progression-Free Survival ,DNA Repair Enzymes ,Treatment Outcome ,030220 oncology & carcinogenesis ,Propensity score matching ,Female ,Surgery ,Neurology (clinical) ,Glioblastoma ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Gross total resection for glioblastoma (GBM) has been associated with better prognosis. However, it is not always feasible, and the threshold for the extent of resection required for better prognosis has been controversial. Therefore, we compared the survival and clinical outcomes of patients with GBM who had undergone partial resection (PR) or biopsy.Of the 110 patients, 32 and 78, who had undergone PR and biopsy, respectively, were enrolled to identify any differences in clinical outcomes. No differences were found in patient demographics between the 2 groups, except for tumor location and mean tumor volume (P = 0.02 and P0.01, respectively). Propensity score matching between the PR and biopsy groups was performed, in which 20 patients each in the PR and biopsy groups were matched.The overall survival (OS) and progression-free survival (PFS) did not differ significantly between the PR and biopsy groups (P = 0.84 and P = 0.48, respectively). After propensity score matching, the differences in OS and PFS between the 2 groups were still not statistically significant (P = 0.51 and P = 0.75, respectively). The hazard ratios for OS and PFS for the PR group compared with biopsy were 0.98 and 0.73, respectively; however, the difference was not statistically significant (P = 0.96 and P = 0.39, respectively). The surgical complication rate was greater in the PR group (14 of 32; 43.7%) than in the biopsy group (9 of 78; 11.5%; P0.01).PR failed to improve survival compared with biopsy for patients with GBM. Moreover, the surgical complication rate in the PR group was greater than that in the biopsy group.
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- 2019
8. Tumor-infiltrating immune cell subpopulations and programmed death ligand 1 (PD-L1) expression associated with clinicopathological and prognostic parameters in ependymoma
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Soo Jeong Nam, Young Hoon Kim, Chang Ohk Sung, Young-Shin Ra, Shin Kwang Khang, Young Hyun Cho, Jeong Hoon Kim, and Ji Eun Park
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Adult ,Male ,Ependymoma ,Cancer Research ,Adolescent ,medicine.medical_treatment ,Immunology ,Kaplan-Meier Estimate ,B7-H1 Antigen ,Young Adult ,03 medical and health sciences ,Lymphocytes, Tumor-Infiltrating ,0302 clinical medicine ,Immune system ,T-Lymphocyte Subsets ,Biomarkers, Tumor ,Tumor Microenvironment ,Humans ,Immunology and Allergy ,Medicine ,Child ,Aged ,CD20 ,Tumor microenvironment ,biology ,business.industry ,Tumor-infiltrating lymphocytes ,Infant, Newborn ,Infant ,FOXP3 ,Immunotherapy ,Middle Aged ,Prognosis ,medicine.disease ,Oncology ,Child, Preschool ,biology.protein ,Cancer research ,Female ,business ,CD8 ,030215 immunology - Abstract
Ependymomas are biologically and clinically heterogeneous tumors of the central nervous system that have variable clinical outcomes. The status of the tumor immune microenvironment in ependymoma remains unclear. Immune cell subsets and programmed death ligand 1 (PD-L1) expression were measured in 178 classical ependymoma cases by immunohistochemistry using monoclonal antibodies that recognized tumor-infiltrating lymphocyte subsets (TILs; CD3, CD4, CD8, FOXP3, and CD20), tumor-associated macrophages (TAMs; CD68, CD163, AIF1), indoleamine 2,3-dioxygenase (IDO)+ cells and PD-L1-expressing tumor cells. Increases in CD3+ and CD8+ cell numbers were associated with a prolonged PFS. In contrast, increased numbers of FOXP3+ and CD68+ cells and a ratio of CD163/AIF1+ cells were significantly associated with a shorter PFS. An increase in the IDO+ cell number was associated with a significantly longer PFS. To consider the quantities of TILs, TAMs, and IDO+ cells together, the cases were clustered into 2 immune cell subgroups using a k-means clustering analysis. Immune cell subgroup A, which was defined by high CD3+, low CD68+ and high IDO+ cell counts, predicted a favorable PFS compared to subgroup B by univariate and multivariate analyses. We found six ependymoma cases expressing PD-L1. All these cases were supratentorial ependymoma, RELA fusion-positive (ST-RELA). PD-L1 expression showed no prognostic significance. This study showed that the analysis of tumor-infiltrating immune cells could aid in predicting the prognosis of ependymoma patients and in determining therapeutic strategies to target the tumor microenvironment. PD-L1 expression in the ST-RELA subgroup suggests that this marker has a potential added value for future immunotherapy treatments.
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- 2018
9. Tumor habitat analysis by magnetic resonance imaging distinguishes tumor progression from radiation necrosis in brain metastases after stereotactic radiosurgery
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Seo Young Park, Young Hyun Cho, Ho Sung Kim, Young Hoon Kim, Ji Eun Park, NakYoung Kim, and Da Hyun Lee
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medicine.medical_specialty ,Receiver operating characteristic ,medicine.diagnostic_test ,business.industry ,Brain Neoplasms ,medicine.medical_treatment ,Area under the curve ,Magnetic resonance imaging ,General Medicine ,Radiosurgery ,Magnetic Resonance Imaging ,Targeted therapy ,Necrosis ,Tumor progression ,medicine ,Effective diffusion coefficient ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiology ,business ,Radiation Injuries ,Neuroradiology - Abstract
The identification of viable tumor after stereotactic radiosurgery (SRS) is important for future targeted therapy. This study aimed to determine whether tumor habitat on structural and physiologic MRI can distinguish viable tumor from radiation necrosis of brain metastases after SRS. Multiparametric contrast-enhanced T1- and T2-weighted imaging, apparent diffusion coefficient (ADC), and cerebral blood volume (CBV) were obtained from 52 patients with 69 metastases, showing enlarging enhancing masses after SRS. Voxel-wise clustering identified three structural MRI habitats (enhancing, solid low-enhancing, and nonviable) and three physiologic MRI habitats (hypervascular cellular, hypovascular cellular, and nonviable). Habitat-based predictors for viable tumor or radiation necrosis were identified by logistic regression. Performance was validated using the area under the curve (AUC) of the receiver operating characteristics curve in an independent dataset with 24 patients. None of the physiologic MRI habitats was indicative of viable tumor. Viable tumor was predicted by a high-volume fraction of solid low-enhancing habitat (low T2-weighted and low CE-T1-weighted values; odds ratio [OR] 1.74, p
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- 2021
10. Risk Factors for High-Grade Meningioma in Brain and Spine: Systematic Review and Meta-analysis
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Jeong Hoon Kim, Young Hyun Cho, Jin Hoon Park, Seok Ho Hong, Sung Woo Roh, Young Hoon Kim, Hong Kyung Shin, and Sang Ryong Jeon
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Male ,medicine.medical_specialty ,Meningioma ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,Histologic grade ,otorhinolaryngologic diseases ,medicine ,Meningeal Neoplasms ,Humans ,Spinal Cord Neoplasms ,Risk factor ,neoplasms ,Sex Characteristics ,business.industry ,Brain Neoplasms ,Odds ratio ,medicine.disease ,Confidence interval ,nervous system diseases ,030220 oncology & carcinogenesis ,Meta-analysis ,Surgery ,Female ,Neurology (clinical) ,Radiology ,Outcome data ,Neoplasm Grading ,Neoplasm Recurrence, Local ,business ,030217 neurology & neurosurgery ,Grade I Meningioma - Abstract
Histologic grade has important implications for the management in meningioma. It is important to understand the risk of high-grade meningioma (grades II and III). In this article, we systematically reviewed the histologic grade of meningioma depending on the location and sex and its relationship with recurrence.The PubMed and Embase databases were systematically searched until February 4, 2020. We included studies that were not restricted to specific anatomic locations, histologic grade, or the sizes of the tumors. The proportion of high-grade meningiomas depending on the location and sex and the odds ratio (OR) of recurrence were pooled using a random-effects model.Outcome data were analyzed for 20,336 tumors from 34 studies. We found different proportions of high-grade meningiomas in the brain (12.8%) (95% confidence interval [CI], 10.5%-15.1%) versus the spine (2.4%) (95% CI, 1.0%-3.7%) (P0.01). Skull base meningiomas (8.7%) (95% CI, 5.8%-11.6%) had a lower proportion of high-grade meningiomas than non-skull base meningiomas (16.5%) (95% CI, 11.9%-21.1%) (P0.01). In addition, high-grade meningiomas were more likely to occur in male patients (18.0%) (95% CI, 10.1%-25.9%) than female patients (7.0%) (95% CI, 3.5%-10.6%) (P = 0.01). Higher rates of recurrence (OR = 13.83) were confirmed for high-grade meningiomas than grade I meningiomas (95% CI, 4.10-46.65) (P0.01).This meta-analysis found that intracranial, nonskull base, and male sex are risk factors for high-grade meningioma, and high-grade meningioma had a much higher recurrence rate as compared with grade I meningioma.
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- 2021
11. Intracranial solitary fibrous tumor/hemangiopericytoma: tumor reclassification and assessment of treatment outcome via the 2016 WHO classification
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Seok Ho Hong, Young Hyun Cho, Dong-Won Shin, Sang Woo Song, Sangjoon Chong, Jeong Hoon Kim, Soo Jeong Nam, and Young Hoon Kim
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Male ,Cancer Research ,medicine.medical_specialty ,Solitary fibrous tumor ,Neurology ,medicine.medical_treatment ,World Health Organization ,Radiosurgery ,medicine ,Humans ,Retrospective Studies ,Hemangiopericytoma ,Clinical pathology ,business.industry ,Hazard ratio ,Retrospective cohort study ,Guideline ,medicine.disease ,Treatment Outcome ,Oncology ,Solitary Fibrous Tumors ,Female ,Neurology (clinical) ,Radiology ,business - Abstract
As per the 2016 World Health Organization (WHO) guidelines on the classification of central nervous system tumors, solitary fibrous tumors (SFTs) and hemangiopericytomas (HPCs) constitute a single disease entity, known as SFT/HPC. This study provides a clinical analysis of these tumors and describes the treatment outcomes of SFT/HPCs. This retrospective study included 76 patients with histopathologically proven SFT/HPC. Reclassification according to the 2016 WHO guideline was done for patients who were diagnosed with SFT or HPC based on the 2007 WHO classification. Recurrence-free survival (RFS) and overall survival (OS) were evaluated for all patients and subgroups. The median follow-up period was 77.9 months. The median RFS and OS were 126.5 and 136.8 months, respectively. The 1-, 5-, 10-, and 15-year RFS rates were 93%, 72%, 40%, and 40%, respectively. The 1-, 5-, 10- and 15-year OS rates were 97%, 89%, 54%, and 35%, respectively. In multivariable analyses, stereotactic radiosurgery (SRS; p = 0.009, hazard ratio [HR] 6.986), female sex (p = 0.023, HR 1.76), and age over 45 (p = 0.037, HR 2.74) were associated with shorter RFS. Patients who underwent SRS as initial treatment had a shorter OS than that of patients who underwent primary resection (p
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- 2021
12. Survival outcome and prognostic factors in anaplastic oligodendroglioma: a single-institution study of 95 cases
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Dong-Won Shin, Young Hyun Cho, Seok Ho Hong, Sang Woo Song, Ji Eun Park, Seungjoo Lee, Soo Jeong Nam, Jeong Hoon Kim, Ho Sung Kim, and Young Hoon Kim
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Adult ,Male ,medicine.medical_specialty ,IDH1 ,Oligodendroglioma ,Anaplastic oligodendroglioma ,lcsh:Medicine ,Subgroup analysis ,Gastroenterology ,Survival outcome ,Disease-Free Survival ,Article ,Young Adult ,Internal medicine ,medicine ,Humans ,Single institution ,lcsh:Science ,Aged ,Cancer ,Univariate analysis ,Multidisciplinary ,business.industry ,Brain Neoplasms ,lcsh:R ,Chemoradiotherapy, Adjuvant ,Middle Aged ,medicine.disease ,Prognosis ,Isocitrate Dehydrogenase ,CNS cancer ,Isocitrate dehydrogenase ,Chromosomes, Human, Pair 1 ,Mutation ,lcsh:Q ,Female ,Chromosome Deletion ,business - Abstract
The aim of this study was to evaluate prognostic factors including surgical, radiographic, and histopathologic analyses in anaplastic oligodendroglioma (AO) patients. We reviewed the electronic records of 95 patients who underwent surgery and were diagnosed with AO for 20 years. The primary endpoints were progression-free survival (PFS) and overall survival (OS). Univariate and multivariable analyses included clinical, histopathological, and radiographic prognostic factors. Subgroup analysis was performed in isocitrate dehydrogenase (IDH1/2)-mutant and 1p/19q-codeleted patients. The median PFS and OS were 24.7 months and 50.8 months, respectively. The 1-, 3-, 5-, and 10-year PFS were 75.8%, 42.9%, 32.4%, and 16.4%, respectively. Furthermore, the 1-, 3-, 5-, and 10-year OS were 98.9%, 76.9%, 42.9%, and 29.7%, respectively. The median PFS and OS of the IDH1/2-mutant and 1p/19q-codeleted patients were 54.2 and 57.8 months, respectively. In univariate analyses, young age, frontal lobe, weak enhancement, gross total resection (GTR), low Ki-67 index, 1p/19q codeletion, and IDH1/2 mutations were associated with a favorable outcome. In multivariable analyses, IDH1/2 mutation was related to better PFS and OS. In subgroup analysis, GTR was associated with favorable outcomes.
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- 2020
13. Hypofractionated stereotactic radiosurgery for large-sized skull base meningiomas
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Doheui Lee, Hyuk-Jin Oh, Young Hyun Cho, KyoungJun Yoon, Do Hoon Kwon, Jeong Hoon Kim, and Chang Jin Kim
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Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Treatment response ,Neurology ,medicine.medical_treatment ,Radiosurgery ,Skull Base Neoplasms ,Meningioma ,03 medical and health sciences ,0302 clinical medicine ,Cyberknife ,parasitic diseases ,medicine ,Meningeal Neoplasms ,Humans ,Aged ,Retrospective Studies ,Aged, 80 and over ,Cumulative dose ,business.industry ,Middle Aged ,medicine.disease ,Prognosis ,Survival Rate ,Skull ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Cavernous sinus ,Female ,Radiation Dose Hypofractionation ,Neurology (clinical) ,Radiology ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Although stereotactic radiosurgery (SRS) has been proven to be effective and safe for treating intracranial meningiomas, concerns have been raised about the use of SRS for large-sized tumors involving the skull base that frequently encroach onto adjacent critical neural structures. The purpose of this study was to investigate the role of hypofractionated SRS as a therapeutic option for large-sized skull base meningiomas. Thirty-one consecutive patients (median age: 55 years, 9 men and 22 women) who had been treated with hypofractionated SRS using CyberKnife for large-sized skull base meningiomas (> 10 cm3 in volume, median of 18.9 cm3, range 11.6–58.2 cm3) were enrolled. All patients harbored middle or posterior skull base tumors, most frequently of cavernous sinus (n = 7, 22.6%), petroclival (n = 6, 19.4%), or tentorial edge (n = 6, 19.4%) locations. SRS was delivered in five daily fractions (range 3–5 fractions) with a median cumulative dose of 27.8 Gy (range 22.6–27.8 Gy). With a median follow-up of 57 months (range 9–98 months), tumor control was achieved for 28 (90.3%) of 31 patients. Treatment response on MRI included partial response (volume decrease > 20%) in 17 (54.8%) patients, stable in 11 (35.5%), and progression (volume increase > 20%) in 3 (9.7%). Of 21 patients with cranial neuropathy, 20 (95.2%) showed improved neurological status. Our current results suggest a promising role of hypofractionated SRS for large-sized skull base megningiomas in terms of tumor control and neurological outcomes. It is a reasonable therapeutic option for select patients.
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- 2020
14. A role of metallothionein-3 in radiation-induced autophagy in glioma cells
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Ha Na Kim, Young Hyun Cho, Jae-Young Koh, Sook-Jeong Lee, and Seunghwan Lee
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Cell Survival ,lcsh:Medicine ,chemistry.chemical_element ,Nerve Tissue Proteins ,Zinc ,Radiation Tolerance ,Article ,Ionizing radiation ,Mice ,Cell Line, Tumor ,Glioma ,Macroautophagy ,Autophagy ,medicine ,Animals ,Humans ,Chelation ,RNA, Small Interfering ,lcsh:Science ,Chelating Agents ,Photons ,Gene knockdown ,Multidisciplinary ,Brain Neoplasms ,Chemistry ,lcsh:R ,Ethylenediamines ,medicine.disease ,Metallothionein 3 ,CNS cancer ,Mechanisms of disease ,Gene Knockdown Techniques ,Cancer research ,Gliogenesis ,Metallothionein ,lcsh:Q ,Lysosomes ,Cancer in the nervous system ,Flux (metabolism) - Abstract
Although metallothionein-3 (MT3), a brain-enriched form of metallothioneins, has been linked to Alzheimer’s disease, little is known regarding the role of MT3 in glioma. As MT3 plays a role in autophagy in astrocytes, here, we investigated its role in irradiated glioma cells. Irradiation increased autophagy flux in GL261 glioma cells as evidenced by increased levels of LC3-II but decreased levels of p62 (SQSTM1). Indicating that autophagy plays a cytoprotective role in glioma cell survival following irradiation, measures inhibiting autophagy flux at various steps decreased their clonogenic survival of irradiated GL261 as well as SF295 and U251 glioma cells. Knockdown of MT3 with siRNA in irradiated glioma cells induced arrested autophagy, and decreased cell survival. At the same time, the accumulation of labile zinc in lysosomes was markedly attenuated by MT3 knockdown. Indicating that such zinc accumulation was important in autophagy flux, chelation of zinc with tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN), induced arrested autophagy in and reduced survival of GL261 cells following irradiation. Suggesting a possible mechanism for arrested autophagy, MT3 knockdown and zinc chelation were found to impair lysosomal acidification. Since autophagy flux plays a cytoprotective role in irradiated glioma cells, present results suggest that MT3 and zinc may be regarded as possible therapeutic targets to sensitize glioma cells to ionizing radiation therapy.
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- 2020
15. Predictive factors for high-grade transformation in benign meningiomas
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Sae Min Kwon, Seok Ho Hong, Chang Jin Kim, Young Hoon Kim, Soo Jeong Nam, Young Hyun Cho, Jeong Hoon Kim, and Hee Jun Yoo
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Adult ,Male ,medicine.medical_specialty ,Multivariate analysis ,Mitotic index ,Meningioma ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,Statistical significance ,otorhinolaryngologic diseases ,medicine ,Meningeal Neoplasms ,Mitotic Index ,Humans ,neoplasms ,Aged ,Retrospective Studies ,business.industry ,General Medicine ,Odds ratio ,Middle Aged ,medicine.disease ,Confidence interval ,nervous system diseases ,Cell Transformation, Neoplastic ,Tumor progression ,030220 oncology & carcinogenesis ,Benign Meningioma ,Surgery ,Female ,Neurology (clinical) ,Radiology ,Neoplasm Recurrence, Local ,business ,030217 neurology & neurosurgery - Abstract
Objective Although they are generally slow-growing benign tumors, meningiomas may recur after surgery with transformation into atypical meningiomas. The purpose of this study was to investigate the radiological and histopathological factors that predict the risk of tumor progression from a benign to an atypical meningioma. Patients and Methods All patients treated for recurrent meningiomas in whom the tumor showed histopathologically confirmed high-grade transformation (HGT) from a benign to an atypical meningioma between 2001 and 2017 were included. To evaluate the predictors of transformation, patient medical records documenting the diagnosis of a benign meningioma at the first surgery prior to second surgery with HGT were reviewed. Each patient was matched with four age- and sex-matched controls who were treated for a benign meningioma. The control group comprised all patients without any recurrence for at least 60 months. Results Fourteen patients with benign meningioma underwent HGT and were included. The median time interval of transformation was 63 months (range, 19–132 months). Multivariate analysis indicated that an increased mitotic index (odds ratio [OR], 10.409; 95 % confidence interval [CI], 1.297–83.549; P = 0.027) was a significant predictor of transformation. Prominent peritumoral edema (OR, 33.822; 95 % CI, 0.935–223.688; P = 0.054) did not reach the statistical significance. Conclusion An increased mitotic index may be used as the predictor for HGT of benign meningiomas. Although these tumors with a high risk for transformation do not meet the diagnostic criteria for atypical meningiomas, they may require more attentive observation and management than other benign meningiomas.
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- 2020
16. Primary central nervous system lymphoma involving the hypothalamic-pituitary axis: a case series and pooled analysis
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Young Hoon Kim, Seok Ho Hong, Jeong Hoon Kim, Young Hyun Cho, and Dong-Won Shin
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Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Neurology ,Adolescent ,Intracranial Neoplasm ,Neurosurgical Procedures ,Central Nervous System Neoplasms ,03 medical and health sciences ,0302 clinical medicine ,hemic and lymphatic diseases ,medicine ,Humans ,Survival rate ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Brain Neoplasms ,Medical record ,Lymphoma, Non-Hodgkin ,Pituitary tumors ,Primary central nervous system lymphoma ,medicine.disease ,Prognosis ,Combined Modality Therapy ,Lymphoma ,Survival Rate ,Oncology ,030220 oncology & carcinogenesis ,Female ,Neurology (clinical) ,Radiology ,Hypothalamic pituitary axis ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Primary central nervous system lymphoma (PCNSL) involving the hypothalamic–pituitary axis (H–P axis) is a rare intracranial neoplasm. We aimed to determine the unique characteristics and treatment outcomes of patients with PCNSL at the H–P axis and review the literature. We retrospectively reviewed the electronic medical records of patients with PCNSL in our institute from 2000 to 2017. We analyzed patient characteristics, clinicopathologic features, imaging results, and treatment outcomes. Furthermore, we searched the PubMed database and gathered more cases from published studies to analyze patient treatment outcomes. A total of 488 patients were diagnosed with central nervous system lymphoma at our institute. Seven (1.4%) patients had H–P axis involvement, five had diffuse large B-cell lymphoma, and two had mucosa-associated lymphoid tissue lymphoma. All patients had anterior pituitary lobe dysfunction, and two had posterior lobe dysfunction. The median progression-free survival (PFS) for seven patients was 29.0 (range: 0.9–48.1) months, and the 3-year survival rate was 42.9%. Pooled analysis included 45 patients. The median PFS for these patients was 7.0 months (0.9–52.0), and the 2-year survival rate was 20%. Univariate and multivariate analyses revealed that the patients with visual field defects had better prognosis (p = 0.0153 and 0.043, respectively). PCNSL at the H–P axis is associated with a higher rate of pituitary dysfunction than other parasellar pathologies. PCNSL at the H–P axis has a worse treatment outcome than PCNSL at other sites. However, visual field defect is related to a favorable prognosis in these patients.
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- 2019
17. Postoperative Neurologic Outcome in Patients with Pituitary Apoplexy After Transsphenoidal Surgery
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Min-Seon Kim, Kyuha Chong, Eun Jung Lee, Chang Jin Kim, Seok Ho Hong, Jeong Hoon Kim, Shin Kwang Khang, Young Hoon Kim, and Young Hyun Cho
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Adenoma ,Adult ,Brain Infarction ,Male ,medicine.medical_specialty ,Visual acuity ,medicine.medical_treatment ,Visual impairment ,Vision Disorders ,030209 endocrinology & metabolism ,Neurosurgical Procedures ,Necrosis ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Full recovery ,Risk Factors ,medicine ,Humans ,Pituitary Neoplasms ,In patient ,Significant risk ,Aged ,Retrospective Studies ,Transsphenoidal surgery ,Palsy ,business.industry ,Pituitary apoplexy ,Recovery of Function ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Treatment Outcome ,Female ,Neurology (clinical) ,medicine.symptom ,business ,Pituitary Apoplexy ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Objective Pituitary apoplexy can cause severe neuro-ophthalmologic or endocrinologic sequelae, requiring timely treatment. The present study was performed to evaluate postoperative neurologic outcomes and to identify their risk factors in patients who underwent transsphenoidal surgery for pituitary apoplexy. Methods Forty-one consecutive patients with pituitary apoplexy who underwent transsphenoidal surgery were reviewed retrospectively. The initial rates of visual acuity (VA) decrease, visual field (VF) defect, and ocular palsy were 34.1%, 46.3%, and 68.3%, respectively. The median maximal diameter and tumoral volume was 2.6 cm (range, 2.0–4.6 cm) and 5.3 cm3 (range, 2.4–38.8 cm3), respectively. Seventeen patients (41.5%) underwent surgery within 7 days. The median follow-up duration was 45 months (range, 12–196 months). Results At the last follow-up, 62.9% (22/35) of patients had made a full recovery from preoperative neurologic deficits, with partial recovery observed in the remaining patients. The rates of improvement and full recovery from VA decrease were 92.9% and 57.1%, respectively; those from VF defect were 94.7% and 36.8%, respectively; and those from ocular palsy were 100.0% and 96.4%, respectively. On multivariate analysis, initial visual impairment score (≥20) was the only significant risk factor for postoperative neurologic sequelae (P Conclusions Ocular palsy was fully recovered in 96.4% patients with pituitary apoplexy after transsphenoidal surgery. Initial visual impairment status was found to be more strongly associated with postoperative neurologic recovery than surgical timing.
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- 2018
18. Hypofractionated stereotactic radiosurgery for pituitary metastases
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Min-Seon Kim, Chang Jin Kim, Haemin Chon, Do Hoon Kwon, KyoungJun Yoon, and Young Hyun Cho
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Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Lung Neoplasms ,Neurology ,medicine.medical_treatment ,Breast Neoplasms ,Pilot Projects ,Radiosurgery ,Breast Neoplasms, Male ,03 medical and health sciences ,0302 clinical medicine ,Anterior pituitary ,medicine ,Humans ,Pituitary Neoplasms ,Aged ,Retrospective Studies ,Pituitary stalk ,Lung ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Treatment Outcome ,medicine.anatomical_structure ,Oncology ,030220 oncology & carcinogenesis ,Radiological weapon ,Diabetes insipidus ,Female ,Neurology (clinical) ,business ,Nuclear medicine ,030217 neurology & neurosurgery - Abstract
Pituitary metastases (PMs) are uncommon, representing only 1% of pituitary lesions. The diagnosis of PMs can be challenging and an optimal management remains to be determined. Here, we present a pilot clinical study on the efficacy and safety of hypofractionated stereotactic radiosurgery (SRS) with an optimized dosimetric plan in treating PMs. Between June 2013 and December 2014, seven consecutive patients (4 men and 3 women; median age 62 years) had been diagnosed with PMs based on their characteristic clinical and radiological features and subsequently treated using hypofractionated SRS. Primary cancers originated from the lung (n = 5) or the breast (n = 2). All patients presented with diabetes insipidus (DI). Anterior pituitary and visual dysfunction were combined in 4 and 3 patients, respectively. On magnetic resonance imaging (MRI), PMs involved the pituitary stalk and/or the posterior lobe in all patients. SRS of a cumulative marginal dose 31 Gy with dose-volume constraints for the optic apparatus was delivered in 5 daily fractions. As results, tumor was locally controlled in all patients with substantial responses on MRI (including complete remission in 4 patients). The median survival time was 14 months (range, 6-24 months) after SRS. DI and visual dysfunction improved in all patients, although anterior pituitary dysfunction did not recover. No patients experienced any deterioration in visual, pituitary, or other cranial nerve functions. These results suggest a promising role of hypofractionated SRS in treating PMs in terms of both tumor control and functional outcomes.
- Published
- 2017
19. Single-fraction versus hypofractionated stereotactic radiosurgery for medium-sized brain metastases of 2.5 to 3 cm
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Young Hyun Cho, KyoungJun Yoon, Doheui Lee, Do Hoon Kwon, and Haemin Chon
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Male ,Cancer Research ,medicine.medical_treatment ,Radiosurgery ,03 medical and health sciences ,0302 clinical medicine ,Statistical significance ,Neoplasms ,medicine ,Humans ,Prospective Studies ,Adverse effect ,Prospective cohort study ,Aged ,Retrospective Studies ,Cumulative dose ,business.industry ,Brain Neoplasms ,Incidence (epidemiology) ,Prognosis ,Survival Rate ,Radiation necrosis ,Neurology ,Oncology ,030220 oncology & carcinogenesis ,Toxicity ,Female ,Neurology (clinical) ,Dose Fractionation, Radiation ,Nuclear medicine ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Given recently suggested utility of hypofractionated stereotactic radiosurgery (SRS) in treating large brain metastases (BMs) > 3 cm, we sought to prospectively control tumor size variable to investigate the efficacy and safety of hypofractionated SRS for medium-sized BMs (2.5 to 3 cm) compared with single-fraction SRS. Between 2011 and 2015, a total of 100 patients with newly diagnosed BMs (n = 105) of 2.5 to 3 cm had been treated with either single-fraction (n = 67; median dose 20 Gy) or hypofractionated SRS (n = 38; median cumulative dose 35 Gy in 5 daily fractions). No patients received any prior or upfront whole brain radiotherapy. In each patient, treatment outcome was measured by local tumor control (LTC), overall and progression-free survival (OS and PFS), and the occurrence of radiation necrosis (RN). With a median follow-up of 14 months, significant differences were observed between the single-fraction versus hypofractionated SRS groups in the incidence of RN (29.9% vs. 5.3%, P
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- 2019
20. Radiosurgical decompression for benign perioptic tumors causing compressive cranial neuropathies: a feasible alternative to microsurgery?
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Kyoung Jun Yoon, Eun Jung Lee, Byungchul Cho, Eun Suk Park, Chang Jin Kim, Young Hyun Cho, and Sung Woo Roh
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Adult ,Decompression ,Male ,Cancer Research ,medicine.medical_specialty ,Neurology ,Adolescent ,medicine.medical_treatment ,Radiosurgery ,Young Adult ,03 medical and health sciences ,Cranial neuropathies ,0302 clinical medicine ,medicine ,Humans ,Aged ,Hypesthesia ,business.industry ,Optic Nerve Neoplasms ,Dose fractionation ,Middle Aged ,Microsurgery ,Cranial Nerve Diseases ,Surgery ,Conformity index ,Treatment Outcome ,Oncology ,030220 oncology & carcinogenesis ,Female ,Radiation Dose Hypofractionation ,Neurology (clinical) ,Radiology ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Several studies have reported the efficacy and safety of hypofractionated stereotactic radiosurgery (hSRS) in the treatment of benign perioptic tumors. This study went further and evaluated the feasibility of hSRS in the treatment of those causing compressive cranial neuropathies (CCNs) among perioptic tumors with special consideration of functional improvement. Twenty-six patients with CCNs (CN II = 19; CN III/IV/VI = 9; CN V = 3) caused by perioptic tumors underwent hSRS between 2011 and 2015. hSRS was delivered in five fractions with a median marginal dose of 27.8 Gy (≈14 Gy in a single fraction, assuming an α/β of three) to a tumor volume of 8.2 ± 8.3 cm3. All tumors except one shrank after treatment, with a mean volume decrease of 35 % (range 4−84 %) during the mean follow-up period of 20 months. In 19 patients (38 eyes) with compressive optic neuropathy, vision improved in 55.3 % of eyes (n = 21), was unchanged in 36.8 % (n = 14), and worsened in 7.9 % (n = 3) (2.6 % after excluding two eyes deteriorated due to transient tumor swelling). A higher conformity index (p = 0.034) and volume of the optic apparatus receiving >23.0 Gy (p = 0.019) were associated with greater tumor shrinkage. A greater decrease in tumor volume (p = 0.035) was associated with a better improvement in vision. Ophthalmoplegia and facial hypesthesia improved in six of nine (66.7 %) and three of three (100 %) patients, respectively. There was no newly developed neurological deficit. Decompressive SRS for benign perioptic tumors causing CCN is feasible using hypofractionation, representing a useful alternative to microsurgical resection.
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- 2016
21. Concurrent Chemoradiotherapy with Temozolomide Followed by Adjuvant Temozolomide for Newly Diagnosed Glioblastoma Patients: A Retrospective Multicenter Observation Study in Korea
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Youn-Soo Lee, Do Hun Lim, In Ah Kim, Shin Hyuk Kang, Tae-Young Jung, Dong-Sup Chung, Se Hoon Kim, Min Kyu Kang, Seok Gu Kang, Kook-Jin Ahn, Il Han Kim, Young Hyun Cho, Jeong Hoon Kim, Chul-Kee Park, Sun-Hwan Kim, Sang Min Yoon, Sung Jin Cho, Jong Hee Chang, Chae-Yong Kim, Chang Ok Suh, Se-Hoon Lee, Yong-Kil Hong, Tae Min Kim, Do-Hyun Nam, Joon Ho Song, Jinhee Kim, Byung Sup Kim, Eun Young Kim, Ho-Shin Gwak, Ho Jun Seol, Chang-Ki Hong, Eui Hyun Kim, Kyung-Hwa Lee, Sun-Chul Hwang, Heon Yoo, and Sun-Il Lee
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Oncology ,Adult ,Male ,Cancer Research ,medicine.medical_specialty ,medicine.medical_treatment ,Dacarbazine ,Biopsy ,Kaplan-Meier Estimate ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Internal medicine ,medicine ,Temozolomide ,Combined Modality Therapy ,Humans ,Antineoplastic Agents, Alkylating ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Brain Neoplasms ,Chemoradiotherapy ,Middle Aged ,Magnetic Resonance Imaging ,Radiation therapy ,Treatment Outcome ,030220 oncology & carcinogenesis ,Toxicity ,Disease Progression ,Original Article ,Female ,business ,Glioblastoma ,MGMT ,Adjuvant ,030217 neurology & neurosurgery ,medicine.drug - Abstract
PURPOSE The purpose of this study was to investigate the feasibility and survival benefits of combined treatment with radiotherapy and adjuvant temozolomide (TMZ) in a Korean sample. MATERIALS AND METHODS A total of 750 Korean patients with histologically confirmed glioblastoma multiforme, who received concurrent chemoradiotherapy with TMZ (CCRT) and adjuvant TMZ from January 2006 until June 2011, were analyzed retrospectively. RESULTS After the first operation, a gross total resection (GTR), subtotal resection (STR), partial resection (PR), biopsy alone were achieved in 388 (51.7%), 159 (21.2%), 96 (12.8%), and 107 (14.3%) patients, respectively. The methylation status of O6-methylguanine-DNA methyltransferase (MGMT) was reviewed retrospectively in 217 patients. The median follow-up period was 16.3 months and the median overall survival (OS) was 17.5 months. The actuarial survival rates at the 1-, 3-, and 5-year OS were 72.1%, 21.0%, and 9.0%, respectively. The median progression-free survival (PFS) was 10.1 months, and the actuarial PFS at 1-, 3-, and 5-year PFS were 42.2%, 13.0%, and 7.8%, respectively. The patients who received GTR showed a significantly longer OS and PFS than those who received STR, PR, or biopsy alone, regardless of the methylation status of the MGMT promoter. Patients with a methylated MGMT promoter also showed a significantly longer OS and PFS than those with an unmethylated MGMT promoter. Patients who received more than six cycles of adjuvant TMZ had a longer OS and PFS than those who received six or fewer cycles. Hematologic toxicity of grade 3 or 4 was observed in 8.4% of patients during the CCRT period and in 10.2% during the adjuvant TMZ period. CONCLUSION Patients treated with CCRT followed by adjuvant TMZ had more favorable survival rates and tolerable toxicity than those who did not undergo this treatment.
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- 2016
22. A Single-Institution Retrospective Study of Jugular Foramen Schwannoma Management: Radical Resection Versus Subtotal Intracranial Resection Through a Retrosigmoid Suboccipital Approach Followed by Radiosurgery
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Young Hyun Cho, Chang Jin Kim, Jeong Hoon Kim, Jun Bum Park, Seok Ho Hong, Eun Jung Lee, and Eun Suk Park
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Radiosurgery ,Skull Base Neoplasms ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Jugular Foramen Schwannoma ,medicine ,Humans ,Minimally Invasive Surgical Procedures ,Cranial Nerve Neoplasms ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,Magnetic resonance imaging ,Retrospective cohort study ,Middle Aged ,Neuroma ,medicine.disease ,Dysphagia ,Surgery ,Treatment Outcome ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Female ,Occipital Lobe ,Neurology (clinical) ,medicine.symptom ,business ,Neurilemmoma ,030217 neurology & neurosurgery ,Jugular foramen ,Cranial Nerve Neoplasm - Abstract
Background Despite advances in skull base surgery, achieving effective surgical management of jugular foramen schwannomas (JFSs) that avoids postoperative cranial nerve (CN) deficits remains a challenge. Subtotal resection followed by radiosurgery (rather than radical resection) is increasingly being viewed as a better treatment strategy. Here, an institutional database was retrospectively analyzed for outcomes after surgical treatment of JFSs to evaluate the optimal strategy for managing JFSs. Methods Twenty-two patients with JFSs were operated on by either radical resection ( n = 13) or conservative resection plus radiosurgery ( n = 9). These 2 different groups were compared in terms of early (≤4 weeks after surgery) and late postoperative functional outcome and oncologic control. Results No deaths occurred in either group, but there were 3 surgery-related complications in the radical resection group. Postoperative CN deficits and additional procedures related to CN morbidity were generally higher in the radical resection group, but the differences were not statistically significant. The conservative surgery group showed a statistically significant improvement in the level of dysphagia and dysphagia-related functional state in the late postoperative period. There was 1 case of recurrence after radical resection over a mean follow-up period of 73 months. All tumors in the conservative surgery group were controlled over a mean period of 34 months. Conclusions Our results suggest that conservative resection of JFSs via a familiar intracranial approach plus radiosurgery may be an effective surgical alternative for improving functional outcome with adequate oncologic control.
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- 2016
23. Prognosis and treatment outcomes of central neurocytomas: clinical interrogation based on a single center experience
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Min Jae Yoon, Sae Min Kwon, Seok Ho Hong, Chang Jin Kim, Joonho Byun, Jeong Hoon Kim, and Young Hyun Cho
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Adult ,Male ,Cancer Research ,medicine.medical_specialty ,medicine.medical_treatment ,Kaplan-Meier Estimate ,Single Center ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Central neurocytoma ,medicine ,Atypia ,Humans ,Neurocytoma ,Retrospective Studies ,Univariate analysis ,business.industry ,Brain Neoplasms ,Hazard ratio ,Brain ,Retrospective cohort study ,medicine.disease ,Prognosis ,Radiation therapy ,Treatment Outcome ,Neurology ,Oncology ,030220 oncology & carcinogenesis ,Cohort ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
Central neurocytoma (CN) is a very rare neuronal neoplasm. The clinical implications of the potential prognostic factors for these lesions, including tumor atypia, have therefore not been clarified. Forty CN patients were enrolled and reclassified as typical or atypical in accordance with an MIB-1 labeling index (LI) of above and below 2%. We classified our retrospective study cohort as 21 (52.5%) typical and 19 (47.5%) atypical CN cases. No significant differences were found in terms of sex, mean age, mean tumor size or tumor location between these groups. Recurrences occurred in 2 (9.5%) typical and 6 (33.3%) atypical cases. The typical CN 2-,3- and 5-year PFS rates were 100%, 100%, 92.3%, and those for the atypical group were 93.8%, 78.1%, 65.1%, respectively (p = 0.02). The PFS rates did not statistically differ by treatment modality (gross total resection alone, subtotal resection (STR) alone and STR plus radiation therapy (RT) or radiosurgery (RS)) either in the whole cohort (p = 0.75) or in the typical CN and atypical CN subgroups (p = 0.45 and 0.98, respectively). An atypical histology was the only prognostic indicator of recurrence by univariate analysis (hazard ratio: 5.40, p = 0.04). An atypical lesion (MIB-LI > 2%) is an important prognostic indicator in CN. The clinical implications of the extent of resection for CN patients are still debatable. The use of STR plus RT or RS may be a viable treatment strategy for CN but different therapeutic and follow-up approaches for atypical CN will be needed.
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- 2018
24. Supratentorial Extraventricular Ependymoma: Retrospective Analysis of 15 Patients at a Single Institution
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Joonho Byun, Jeong Hoon Kim, Young Hyun Cho, Chang Jin Kim, Young Hoon Kim, and Seok Ho Hong
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Ependymoma ,Adult ,Male ,medicine.medical_specialty ,Adolescent ,Adjuvant chemotherapy ,World health ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Biopsy ,Retrospective analysis ,Medicine ,Humans ,Single institution ,Child ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Supratentorial Neoplasms ,Subtotal Resection ,Middle Aged ,medicine.disease ,Gross Total Resection ,Surgery ,030220 oncology & carcinogenesis ,Child, Preschool ,Female ,Neurology (clinical) ,Neoplasm Recurrence, Local ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Supratentorial extraventricular ependymoma (STEE) is an extremely rare central nervous system (CNS) neoplasm, the clinical characteristics and optimal treatment of which remain unclear. We retrospectively analyzed the clinical characteristics and treatment outcomes of 15 patients with STEE.Fifteen patients with STEE were identified, and their clinical, radiologic, and surgical records were reviewed.The 15 patients included 6 males (40%) and 9 females (60%), with a median age of 15 years. Nine patients (60%) underwent gross total resection, 5 patients (33.3%) underwent subtotal resection, and 1 patient (6.7%) underwent biopsy. Eight patients received adjuvant radiotherapy, and 3 received adjuvant chemotherapy. The 5-year overall survival (OS) rates of patients with World Health Organization (WHO) grade II and grade III STEE were 100% and 30%, respectively, and the corresponding 2-year progression-free survival (PFS) rates were 77.8% and 20%. The differences in OS and PFS rates between WHO grades II and III STEE were statistically significant (P0.01 and 0.02, respectively). Anaplastic histology (WHO grade III) was a poor prognostic factor for PFS (P = 0.04). The recurrence pattern was local recurrence in all patients; all cases were treated primarily by redo surgery. Three patients with recurrent WHO grade II STEE were alive at more than 64, 52, and 44 months after redo surgery.STEE is an extremely rare CNS neoplasm. The histological grade of STEE is an important prognostic factor. Microsurgical resection might play a major role in both initial treatment and treatment of recurrent tumors.
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- 2018
25. Transzygomatic approach with anteriorly limited inferior temporal gyrectomy for large medial tentorial meningiomas
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Eun Suk Park, Eun Jung Lee, Chang Jin Kim, Young Hyun Cho, Jeong Hoon Kim, and Seok Ho Hong
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Meningioma ,Epidural hematoma ,Inferior temporal gyrus ,Meningeal Neoplasms ,medicine ,Humans ,Craniotomy ,Neuroradiology ,medicine.diagnostic_test ,business.industry ,Interventional radiology ,Middle Aged ,medicine.disease ,Psychosurgery ,Surgery ,Hemiparesis ,Female ,Neurology (clinical) ,Neurosurgery ,medicine.symptom ,business - Abstract
Tentorial meningiomas near the middle third of the medial tentorial edge with supratentorial extension are usually removed via the subtemporal approach. This approach, however, may not be practical, especially for huge tumors extending to the posterior subtemporal space. This study describes the use of the transzygomatic approach with anteriorly limited inferior temporal gyrectomy (TZ-AITG) to remove these large tumors. Between 2008 and 2012, five patients with symptomatic tentorial meningiomas (median diameter, 5.2 cm; range, 4.0–5.7 cm) near the middle third of the medial tentorial edge with supratentorial extension underwent TZ-AITG, consisting of zygomatic osteotomy, low-positioned craniotomy, and resection of the inferior temporal gyrus around 4 cm from the tip. Tumors were completely resected in all patients. Postoperatively, none had a newly developed neurological morbidity, and none died. Of three patients with preoperative hemianopia, two showed improvement and one remained stationary. One patient with preoperative hemiparesis recovered completely. All patients returned to their normal activities during the follow-up period. Surgical morbidities included epidural hematoma and chronic subdural hematoma in one patient each, with both requiring evacuation. TZ-AITG may be a good alternative to the subtemporal approach for large tentorial meningiomas near the middle third of the medial tentorial edge. TZ-AITG provides access to the lesions and visualization of the middle fossa, facilitating early feeder control while minimizing brain retraction, thus reducing potential injury to the vein of Labbe. TZ-AITG is also safe and feasible in minimizing neurological compromise.
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- 2015
26. Clinical outcomes of primary intracranial malignant melanoma and metastatic intracranial malignant melanoma
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Jeong Hoon Kim, Chang Jin Kim, Seok Ho Hong, Eun Suk Park, Young Hoon Kim, Young Hyun Cho, Seungjoo Lee, and Joonho Byun
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Oncology ,Adult ,Male ,medicine.medical_specialty ,Resection ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Internal medicine ,Overall survival ,Medicine ,Humans ,CNS TUMORS ,Survival rate ,Melanoma ,Aged ,Retrospective Studies ,business.industry ,Brain Neoplasms ,Clinical course ,General Medicine ,Middle Aged ,medicine.disease ,Tumor recurrence ,Survival Rate ,Treatment Outcome ,030220 oncology & carcinogenesis ,Surgery ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Median survival ,Follow-Up Studies - Abstract
Objectives Primary intracranial malignant melanoma (PIMM) is extremely rare central nervous system (CNS) tumor and known for only composed 0.07% of the CNS tumors. PIMM composed only 1% of malignant melanoma and accordingly their clinical behavior and prognosis are not well documented. So, herein, we report our experience of pathologically proven PIMM, and compared their clinical characteristics and outcome with metastatic intracranial malignant melanoma (MIMM). Patients and methods Our institutional database was reviewed for patients who diagnosed as PIMM and MIMM pathologically between 1996–2016. As a result, a total of 6 patients of PIMM and 18 patients of MIMM were identified and analyzed. All these patients’ clinical, radiological, histopathological and surgical records were obtained and reviewed. Results The median age of PIMM patients at initial surgery was 54.5 years (range, 30–60 years). During the mean follow-up of 12.8 months (range: 9–21 months), tumor recurrence occurred in 5 patients (83.3%). The overall survival rates of PIMM at 6, 9, 12 and 18 months were 100%, 83%, 50% and 25%. The PFS rates of PIMM at 3,6,9 and 12 months were 66.7%, 50%, 16.7% and 16.7%. The overall survival rates and progression-free survival rate difference between PIMM and MIMM were not statistically significant. (p = 0.723 and p = 0.6, respectively). Conclusion According to our experience, PIMM is very aggressive malignant tumor. Its median survival was less than 1 year. We suggest that maximal safe resection plus adjuvant RT and CTX for intracranial malignant melanoma considering highly aggressive clinical course of this tumors.
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- 2017
27. Sox7 promotes high-grade glioma by increasing VEGFR2-mediated vascular abnormality
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Seok Ho Hong, Heung Kyu Lee, Seongyeol Park, Hyung-Seok Kim, Ju Hee Kim, Dong Sun Oh, Young Seok Ju, Seungjoo Lee, Jeong Hoon Kim, Jee Myung Yang, Kangsan Kim, Young Hoon Kim, David T. Shima, Il Kug Kim, Young Hyun Cho, Chan Soon Park, Injune Kim, Jong Bae Park, Gou Young Koh, and Eunhyeong Lee
- Subjects
0301 basic medicine ,Regulatory T cell ,Immunology ,Down-Regulation ,Article ,03 medical and health sciences ,Mice ,Downregulation and upregulation ,Immunity ,Calcium-binding protein ,Glioma ,medicine ,SOXF Transcription Factors ,Immunology and Allergy ,Animals ,Humans ,Clinical significance ,Research Articles ,Adaptor Proteins, Signal Transducing ,biology ,business.industry ,Calcium-Binding Proteins ,Intracellular Signaling Peptides and Proteins ,Endothelial Cells ,Membrane Proteins ,medicine.disease ,Prognosis ,Phenotype ,Vascular Endothelial Growth Factor Receptor-2 ,Up-Regulation ,030104 developmental biology ,medicine.anatomical_structure ,Cancer research ,biology.protein ,cardiovascular system ,Blood Vessels ,Antibody ,Neoplasm Grading ,business ,Gene Deletion - Abstract
Antiangiogenic therapy has a clinical benefit in only a subpopulation of high-grade glioma (HGG) patients. Kim et al. show that in an orthotopic HGG model, high levels of Sox7 in tumor vessels correlate with improved survival by anti-VEGFR2 antibody, suggesting a potential mechanism of heterogeneous therapeutic outcome to antiangiogenic therapy., High-grade glioma (HGG) is highly angiogenic, but antiangiogenic therapy has transient clinical benefit in only a fraction of patients. Vascular regulators of these heterogeneous responses remain undetermined. We found up-regulation of Sox7 and down-regulation of Sox17 in tumor endothelial cells (tECs) in mouse HGG. Sox7 deletion suppressed VEGFR2 expression, vascular abnormality, hypoxia-driven invasion, regulatory T cell infiltration, and tumor growth. Conversely, Sox17 deletion exacerbated these phenotypes by up-regulating Sox7 in tECs. Anti-VEGFR2 antibody treatment delayed tumor growth by normalizing Sox17-deficient abnormal vessels with high Sox7 levels but promoted it by regressing Sox7-deficient vessels, recapitulating variable therapeutic responses to antiangiogenic therapy in HGG patients. Our findings establish that Sox7 promotes tumor growth via vessel abnormalization, and its level determines the therapeutic outcome of VEGFR2 inhibition in HGG. In 189 HGG patients, Sox7 expression was heterogeneous in tumor vessels, and high Sox7 levels correlated with poor survival, early recurrence, and impaired vascular function, emphasizing the clinical relevance of Sox7 in HGG.
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- 2017
28. Factors affecting hearing deterioration in vestibular schwannoma patients treated with gamma knife radiosurgery: the Asan Medical Center experience
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Jong Woo Chung, Young Hyun Cho, Do Heui Lee, Joong Ho Ahn, Marn Joon Park, Young Jun Choi, and Hong Ju Park
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Gamma knife radiosurgery ,Acoustic neuroma ,Schwannoma ,Radiation Dosage ,Radiosurgery ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,otorhinolaryngologic diseases ,Medicine ,Humans ,Hearing Loss ,Cochlea ,Aged ,Vestibular system ,Analysis of Variance ,business.industry ,Medical record ,General Medicine ,Odds ratio ,Neuroma, Acoustic ,Middle Aged ,medicine.disease ,Surgery ,Otorhinolaryngology ,Hearing level ,030220 oncology & carcinogenesis ,Female ,business ,030217 neurology & neurosurgery - Abstract
Objectives: To investigate the changes in hearing and to determine factors predicting hearing deterioration in patients with vestibular schwannoma (VS) who undergo gamma knife radiosurgery (GKRS). Design: A retrospective review of medical records in patients diagnosed with VS and initially treated with GKRS at a tertiary care medical center between 1995 and 2015 was performed. Tumor factors (location, volume), parameters related to irradiation to the tumor and cochlea, and distance between the tumor and cochlea were reviewed. Results: Fifty-six patients were included in the final analysis with a mean observation period following GKRS as 24.4 ± 27.8 months. Prior to GKRS, the average pure tone threshold at 500, 1k, 2k, and 4k Hz (PTA4) was 51.0 ± 29.7 dB HL. After GKRS, the mean PTA4 was 71.6 ± 33.3 dB HL. Significant independent odds ratios for hearing deterioration were 8.5 for extracanalicular tumors, 18.8 for more than 10 shots in GKRS, and 12.2 for a distance between the tumor center and cochlea modiolus less than 20 mm. Conclusions: A significant hearing deterioration was shown in 2 years after GKRS. Tumor location, number of radiation shots, and distance between the tumor and cochlea affected hearing level after GKRS.
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- 2017
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29. Changes in Graft Thickness After Skull Defect Reconstruction With Autogenous Split Calvarial Bone Graft
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Young Hyun Cho, Seok Ho Hong, Jong Woo Choi, Kyung S. Koh, Young Shin Ra, and Tack Jin Chang
- Subjects
Adult ,Male ,Reoperation ,Adolescent ,Esthetics ,Dentistry ,Skull defect ,Young Adult ,Postoperative Complications ,Humans ,Medicine ,Autogenous bone ,Autografts ,Child ,skin and connective tissue diseases ,Aged ,Bone Transplantation ,Ideal (set theory) ,business.industry ,Skull ,General Medicine ,Middle Aged ,Plastic Surgery Procedures ,Otorhinolaryngology ,Patient Satisfaction ,Female ,Surgery ,sense organs ,Tomography, X-Ray Computed ,business ,Follow-Up Studies - Abstract
The ideal material for primary reconstruction of skull defect would be the autogenous bone. However, the long-term evaluation regarding the change in bone graft thickness has not been reported. In this article, we analyzed the thickness changes of the graft according to the time period. Between March 2005 and February 2011, a total of 29 patients underwent skull reconstruction with autogenous split calvarial bone grafts. After applying exclusion criteria, computed tomographic (CT) images of 15 patients were analyzed. The donor bone was harvested in full thickness as 1 piece and then as split. One half of the bone plate was transferred to the defect site; the other half, to the donor site. Both halves were fixed with titanium plates. To compare graft thickness changes, immediate postoperative and follow-up CT scans were analyzed by a single researcher. An anatomic reference was appointed for each patient, and the thickness of the graft on the same level was measured on time-series CT images. Collected data were analyzed with a polynomial random coefficient model. The main causes of the skull defects were trauma and tumor excision. In all cases, the graft thickness was not decreased but even increased in both the donor and recipient sites. The mean graft thicknesses between 6 months and 1 year after the surgery as well as those between 2 and 3 years after the surgery were 1.24-times and 1.56-times thicker than the immediate postoperative thickness, respectively. Graft thickness turned out to be either maintained or increased over time.
- Published
- 2014
30. Analysis of the results of recurrent intracranial meningiomas treated with re-radiosurgery
- Author
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Hyun Jung Kim Rn, Young Hyun Cho, Jeong Hoon Kim, M. H. Kim, Do Hee Lee, and Do Hoon Kwon
- Subjects
Adult ,Male ,Reoperation ,medicine.medical_specialty ,medicine.medical_treatment ,Intracranial Neoplasm ,Radiosurgery ,Meningioma ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Outcome Assessment, Health Care ,medicine ,Meningeal Neoplasms ,Humans ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,Microsurgery ,Middle Aged ,medicine.disease ,Surgery ,Exact test ,030220 oncology & carcinogenesis ,Benign Meningioma ,Female ,Neurology (clinical) ,Radiology ,Neoplasm Recurrence, Local ,business ,030217 neurology & neurosurgery ,Recurrent Meningioma ,Follow-Up Studies - Abstract
Objects Meningioma is the most common intracranial neoplasm, comprising approximately 30% of all primary intracranial tumors (Claus et al., 2005) [1] . Treatment options include observation, microsurgical resection, stereotactic radiosurgery (SRS), and whole brain radiation therapy (WBRT). Gamma knife radiosurgery (GKRS) is a very effective treatment for intracranial meningiomas; previous studies showed the tumor control rate at 5–10 years of follow-up as 84.3%–100% in all cases (Feigl et al., 2005; Linskey et al., 2005; Malik et al., 2005; Aichholzer et al., 2000; Hakim et al., 1998; Chang and Adler 1997; Lunsford, 1994; Ganz et al., 1993) [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] . Many studies have discussed issues like optimal dose, conformal configurations, and adverse effects to improve the treatment result with GKRS (Malik et al., 2005; Kenai et al., 2005; Rowe et al., 2004; Shrieve et al., 2004) [4] , [10] , [11] , [12] . There are some cases in which the radiosurgery result is unfavorable and perhaps further treatment is needed. In these cases, re-radiosurgery can be an option. However, there have not been comprehensive studies discussing the issues of re-radiosurgery. Therefore, we analyzed the result of re-radiosurgery for recurrent meningiomas and their impact on clinical outcomes. Methods From 1995 to 2015, we retrospectively reviewed 1163 patients who underwent GKRS for intracranial meningioma at the Asan Medical Center. Patients with multiple meningiomas or a follow-up with a period of less than a year were excluded from this study. Finally, 865 patients were enrolled in this study. Clinical symptoms and brain magnetic resonance imaging (MRI) scans were assessed by neurosurgeons. When tumor size increased together with newly developed neurologic symptoms, further management, such as microsurgical resection or SRS, was considered. Histologic analysis of the resected tumors was performed by neuropathologists. Clinical data, including patient’s sex, age, and tumor locations were recorded. Treatment data included tumor volume, tumor grade, radiation dose, and presence of edema. Final outcome data including follow-up period, time to progression, interval between first and second radiosurgery courses and interval between microsurgery and radiosurgery were obtained. Results Among 865 patients, tumor recurrence was found in 63 patients (7.28%). Seven patients showed transient tumor growth after GKRS. These patients have been under close observation without any further treatments. Fifty-six patients (6.47%) showed permanent tumor growth on follow-up MRI. Thirty-three patients from this group underwent repeated radiosurgery owing to tumor growth, resulting in a re-irradiation rate of 3.82% at our radiosurgery center. The other 23 patients were treated using methods other than re-radiosurgery. Among the 33 patients, 25 underwent microsurgical resection prior to their initial course of GKRS, and the other 8 were treated with re-radiosurgery only. An analysis was performed to determine factors that may have a role in treatment results. Of the many variables, tumor grade (p = 0.004, Fisher’s exact test) was the only significant factor for progression-free survival (PFS). Thirteen patients with unbiopsied or benign meningioma showed stable tumor size, while there was tumor growth in 8 patients. Among high-grade meningioma patients, 3 and 9 showed stable disease and tumor growth, respectively. As a result of re-radiosurgery, 11 out of 17 patients showed tumor growth and needed further treatments; this involved a third GKRS for 4 patients, microsurgical resection for 6 patients, and cyber knife radiosurgery (CKRS) for 1 patient. Four patients from this group were also treated with WBRT. Conclusion We analyzed the results of re-radiosurgery for recurrent meningiomas and observed that World Health Organization (WHO) grade II and III was significantly associated with a lower PFS rate compared with low-grade meningiomas (p = 0.004). Conversely, patients with benign meningioma or unbiopsied tumors had much better results. Hence, re-radiosurgery is recommended for patients with unknown or benign meningiomas if their first GKRS result is unsatisfactory. However, re-radiosurgery should be considered carefully for recurrent high-grade tumors. Owing to the small number of recurrent meningioma patients treated with re-radiosurgery, further studies are required to delineate the role of this treatment.
- Published
- 2016
31. Hypofractionated intensity-modulated radiotherapy using simultaneous integrated boost technique with concurrent and adjuvant temozolomide for glioblastoma
- Author
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Sang Min, Yoon, Jeong Hoon, Kim, Sang Joon, Kim, Shin Kwang, Khang, Seong Soo, Shin, Young Hyun, Cho, Eunjin, Jwa, Jin-Hong, Park, and Seung Do, Ahn
- Subjects
Adult ,Male ,Cancer Research ,Kaplan-Meier Estimate ,Disease-Free Survival ,030218 nuclear medicine & medical imaging ,Necrosis ,03 medical and health sciences ,0302 clinical medicine ,Temozolomide ,Humans ,Treatment Failure ,Antineoplastic Agents, Alkylating ,Aged ,Brain Neoplasms ,Brain ,Chemoradiotherapy, Adjuvant ,General Medicine ,Middle Aged ,Dacarbazine ,Treatment Outcome ,Oncology ,Chemotherapy, Adjuvant ,030220 oncology & carcinogenesis ,Female ,Dose Fractionation, Radiation ,Radiotherapy, Intensity-Modulated ,Glioblastoma - Abstract
Aims and background We assessed the therapeutic efficacy of combined hypofractionated intensity-modulated radiotherapy with temozolomide in patients with primary glioblastoma. Methods and study design Thirty-nine patients with histologically confirmed glioblastoma were accrued. Using the simultaneous integrated boost technique, a dose of 50 Gy in 5-Gy fractions was applied to the gross tumor volume, together with 40 Gy in 4-Gy fractions and 30 Gy in 3-Gy fractions to the 1- and 2-cm margins from the gross tumor volume, respectively. Patients were also treated with concurrent temozolomide during intensity-modulated radiotherapy, followed by six cycles of adjuvant temozolomide. Results Median follow-up was 16.8 months (range, 4.3–54.3). Tumor progression was observed in 28 patients (71.8%), and the median time to progression was 6.8 months. Median survival was 16.8 months, and it was affected significantly by the extent of surgery. During adjuvant temozolomide treatment, 3 patients (9.7%) developed grade 3–4 hematologic or hepatic toxicity. Radiation necrosis developed in 7 patients (17.9%) and massive necrosis, requiring emergency surgery, in 1 patient (2.6%). Conclusions The regimen of hypofractionated intensity-modulated radiotherapy with temozolomide showed a relatively good outcome in patients with glioblastoma. Further studies are required to define the optimal fraction size for glioblastoma using this highly sophisticated radiation technique.
- Published
- 2013
32. Analysis the causes of radiosurgical failure in intracranial meningiomas treated with radiosurgery
- Author
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Young Hyun Cho, Chang Jin Kim, Jeong Hoon Kim, Do Hoon Kwon, and M. H. Kim
- Subjects
Adult ,Male ,Reoperation ,medicine.medical_specialty ,Microsurgery ,medicine.medical_treatment ,Gamma knife radiosurgery ,Radiosurgery ,Meningioma ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,medicine ,Meningeal Neoplasms ,Humans ,Tumor growth ,Treatment Failure ,Aged ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Radiation therapy ,Exact test ,Outcome and Process Assessment, Health Care ,030220 oncology & carcinogenesis ,Female ,Neurology (clinical) ,Neoplasm Recurrence, Local ,business ,030217 neurology & neurosurgery - Abstract
Objectives Surgical resection is a primary indication for intracranial meningioma. Radiosurgery is also an excellent treatment modality for postoperative residual tumors, or tumors in high-risk locations, such as the skull base. Despite multimodality treatments, there are some cases in which radiosurgery fails and surgical resection or re-radiosurgery is required. However, there has not been a comprehensive study focusing on the causes of secondary treatment for local recurrence or a new mass that develops outside the target area after radiosurgery. Hence, we analyzed the causes of radiosurgical failure in patients with meningioma. Methods From 2000 to 2015, we retrospectively reviewed 1086 patients who underwent gamma knife radiosurgery (GKRS) for intracranial meningioma at the Asan Medical Center. Multiple meningiomas or tumors with a volume greater than 7000mm 3 were excluded. All patients had a minimum follow-up of 12 months. Finally, 771 patients were enrolled in this study. Clinical symptoms and brain MRI findings were assessed by neurosurgeons. When the tumor size increased and was accompanied by newly developed neurological symptoms, further management was considered (e.g. microsurgical resection and stereotactic radiosurgery). Histological analyses of the resected tumors were performed by neuropathologists. Results Among the 771 patients, tumor growth was observed in 60 patients (7.78%). Seven patients showed transient tumor growth after GKRS. These patients have been under close observation without any further treatment. Thirty patients (3.89%) underwent re-radiosurgery for tumor control. Another 23 patients underwent procedures other than re-radiosurgery; 8 underwent microsurgical resection, 3 underwent cyber knife radiosurgery (CKRS), 1 underwent radiation therapy, and 8 were closely followed-up. Three patients visited other clinics or were lost to follow-up. Of the remaining 30 patients, 22 (group 1) underwent microsurgical resection prior to their initial course of GKRS and the other 8 (group 2) were treated only with re-radiosurgery. In group 1, recurrence rates after radiosurgery were 2.47% (n=19) and 0.39% (n=3) for local and distant recurrence, respectively. In group 2, recurrence rates after radiosurgery were 0.52% (n=4) and 0.52% (n=4) for local and distant recurrence, respectively. An analysis was performed to determine the factors that may result in differences between the two groups. Of the many variables, local recurrence ( p =0.0331, Fisher's exact test) was the only significant factor. Conclusion We analyzed the causes of radiosurgical failure in meningioma patients and observed that microsurgery before radiosurgery was significantly associated with a high local recurrence rate compared with primary radiosurgery. Furthermore, the percentage of local recurrence cases that required secondary radiosurgery was as low as 2.98%. This result is comparable with that of microsurgical resection, which is the mainstay of treatment for meningioma.
- Published
- 2016
33. Pyrophosphatase overexpression is associated with cell migration, invasion, and poor prognosis in gastric cancer
- Author
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Young-Joon Lee, Sang-Kyung Choi, Jiyun Yoo, Bok-Im Cho, Soon-Chan Hong, Jae Won Kim, Chang-Won Lee, Seok Hwan Shin, Gyung Hyuck Ko, Yoon Seok Heo, Sang-Ho Jeong, Woo-Song Ha, and Young Hyun Cho
- Subjects
Male ,Stomach neoplasm ,Pathology ,medicine.medical_specialty ,Blotting, Western ,Biology ,Real-Time Polymerase Chain Reaction ,Metastasis ,Immunoenzyme Techniques ,Cell Movement ,Stomach Neoplasms ,Biomarkers, Tumor ,Tumor Cells, Cultured ,medicine ,Humans ,Electrophoresis, Gel, Two-Dimensional ,RNA, Messenger ,RNA, Small Interfering ,Lymph node ,Cell Proliferation ,Neoplasm Staging ,Inorganic pyrophosphatase ,Reverse Transcriptase Polymerase Chain Reaction ,Stomach ,Cancer ,Cell migration ,General Medicine ,Middle Aged ,Prognosis ,medicine.disease ,Adenocarcinoma, Mucinous ,Survival Rate ,Inorganic Pyrophosphatase ,medicine.anatomical_structure ,Tissue Array Analysis ,Case-Control Studies ,Lymphatic Metastasis ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Disease Progression ,Cancer research ,Biomarker (medicine) ,Immunohistochemistry ,Female ,Neoplasm Recurrence, Local - Abstract
Inorganic pyrophosphatase (PPase) catalyzes the hydrolysis of pyrophosphate to form orthophosphate. Pyrophosphate can substitute for ATP under certain circumstances. We previously conducted a proteomic analysis to investigate tumor-specific protein expression in gastric cancer, and PPase was identified as a potential gastric tumor-specific marker; it was therefore selected for further study. Clinicopathological analysis, using proteomic analysis and immunohistochemistry, was used to validate PPase as a prognostic marker in gastric cancers. Proteomic analysis showed that PPase was overexpressed in patients with lymph node (LN) metastases and high tumor node metastasis (TNM) stages (p < 0.05). Based on immunohistochemistry, patients whose tumors overexpressed PPase had higher T stages, LN metastasis, a higher TNM stage, a higher cancer recurrence rate, and shorter survival times than patients whose tumors exhibited PPase underexpression (p < 0.05). Gain-of-function and loss-of-function approaches were employed to examine the malignant phenotypes of PPase-overexpressing or PPase-depleted cells. A decrease in PPase expression caused a significant decrease in gastric cancer cell migration and invasion in vitro, whereas forced overexpression of PPase enhanced migration but not invasion. Our findings indicate that PPase is involved in gastric tumor progression and that PPase may be a useful marker for poor prognosis of human gastric cancers.
- Published
- 2012
34. Experiences on two different stereotactic radiosurgery modalities of Gamma Knife and Cyberknife in treating brain metastases
- Author
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Jae Hong Park, KyoungJun Yoon, Chang Jin Kim, Sung Woo Roh, Seon-Ok Kim, Do Hoon Kwon, Doheui Lee, Young Hyun Cho, Jeong Hoon Kim, and Jung Min Lee
- Subjects
Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Normal tissue ,Gamma knife ,Radiation Dosage ,Radiosurgery ,Cyberknife ,medicine ,Humans ,Neoplasm Metastasis ,Aged ,business.industry ,Brain Neoplasms ,Dose fractionation ,Middle Aged ,Tumor Burden ,Radiation necrosis ,Treatment Outcome ,Toxicity ,Surgery ,Female ,Neurology (clinical) ,Neurosurgery ,Dose Fractionation, Radiation ,business ,Nuclear medicine ,Follow-Up Studies - Abstract
In this study, we compared the dosimetric properties between Gamma Knife (GK) and Cyberknife (CK), and investigated the clinical implications in treating brain metastases (BMs). Between 2011 and 2013, 77 patients treated with either single-fraction GK for small BMs (n = 40) or fractionated CK for large BMs >3 cm (n = 37) were analyzed. Among a total of 160 lesions, 81 were treated with GK (median, 22 Gy) and 38 (large lesions) with three- or five-fraction CK (median, 35 Gy). The median tumor volume was 1.0 cc (IQR, 0.12–4.4 cc) for GK and 17.6 cc (IQR, 12.8–23.7 cc) for fractionated CK. A lesion-to-lesion dosimetric comparison was performed using the identical contour set in both systems. The mean dose to tumor was significantly higher in GK by 1.25-fold (P
- Published
- 2015
35. Gamma Knife surgery for treating brain metastases arising from hepatocellular carcinomas
- Author
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Eun Suk, Park, Do Hoon, Kwon, Jun Bum, Park, Do Hee, Lee, Young Hyun, Cho, Jeong Hoon, Kim, and Chang Jin, Kim
- Subjects
Adult ,Male ,Carcinoma, Hepatocellular ,Brain Neoplasms ,Liver Neoplasms ,Kaplan-Meier Estimate ,Middle Aged ,Prognosis ,Radiation Dosage ,Radiosurgery ,Treatment Outcome ,Humans ,Female ,Karnofsky Performance Status ,Aged ,Follow-Up Studies ,Retrospective Studies - Abstract
Brain metastases from hepatocellular carcinoma (HCC) are rare, and the evidence of the effectiveness of Gamma Knife surgery (GKS) in this disease is lacking. The authors report their institutional experience with GKS in patients with brain metastases from HCCs.The authors retrospectively reviewed the medical records of 73 consecutive patients who had a combined total of 141 brain metastases arising from HCCs and were treated with GKS. Sixty-four (87.7%) patients were male, and the mean age of the patients was 52.5 years (range 30-79 years). The mean tumor volume was 7.35 cm(3) (range 0.19-33.7 cm(3)). The median margin dose prescribed was 23 Gy (range 15-32 Gy). Univariate and multivariate survival analyses were performed to identify possible prognostic factors of outcomes.The estimated rate of local tumor control was 79.6% at 3 months after GKS. The median overall survival time after GKS was 16 weeks. The actuarial survival rates were 76.7%, 58.9%, and 26.0% at 4, 12, and 24 weeks after GKS, respectively. In the univariate analysis, an age of ≤ 65 years, Child-Pugh Class A (pertaining to liver function), high Karnofsky Performance Scale score (≥ 70), and low Radiation Therapy Oncology Group recursive partitioning analysis class (I or II) were positively associated with the survival times of patients. No statistically significant variable was identified in the multivariate analysis.Although survival was extremely poor in patients with brain metastases from HCCs, GKS showed acceptable local tumor control at 3 months after the treatment. The authors suggest that GKS represents a noninvasive approach that may provide a valuable option for treating patients with brain metastases from HCCs.
- Published
- 2014
36. Fiducial-free CyberKnife radiosurgery for residual metastatic spinal tumor after decompression and instrumentation
- Author
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Jae Hong Park, Sung Woo Roh, Jin Hoon Park, Young Hyun Cho, Sang Ryong Jeon, and Chang Jin Kim
- Subjects
Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Neoplasm, Residual ,Decompression ,Radiography ,medicine.medical_treatment ,Radiosurgery ,Residual ,Cyberknife ,Physiology (medical) ,Image Processing, Computer-Assisted ,medicine ,Humans ,Spinal Cord Neoplasms ,Instrumentation (computer programming) ,Aged ,Neurologic Examination ,Muscle Weakness ,Spinal Neoplasms ,business.industry ,Liver Neoplasms ,General Medicine ,Middle Aged ,Decompression, Surgical ,Magnetic Resonance Imaging ,Radiation therapy ,Surgery, Computer-Assisted ,Neurology ,Surgery ,Neurology (clinical) ,Radiology ,CyberKnife Radiosurgery ,Fiducial marker ,business - Abstract
Stereotactic spinal radiotherapy is a promising technology for use in the multidisciplinary management of benign and malignant spinal tumors. We present two patients with residual metastatic spinal tumors and their treatment with CyberKnife (Accuray, Sunnyvale, CA, USA) after decompression and instrumentation, one of which was successful and the other not. A 73-year-old male patient was admitted with bilateral extremity weakness (Grade IV) and voiding difficulty that had developed 2 days previously. CyberKnife treatment for the residual tumor after surgery with decompression and instrumentation was attempted, but could not be performed due to imaging interference caused by the instrumentation. A second patient, a 49-year-old male, was admitted with right extremity weakness and voiding difficulty that had developed 5 months previously. In this patient, we were able to perform CyberKnife treatment on the residual tumor after decompression and instrumentation. Based on these two patients, we believe that fiducial-free CyberKnife treatment is not suitable for treatment of residual metastatic spinal tumors at the upper thoracic levels, after decompression with instrumentation. This is due to the difficulties in matching digitally reconstructed radiographs with live radiographic images, as a result of the larger inclination and smaller vertebral body surface at the upper thoracic level.
- Published
- 2012
37. Hearing loss following ventriculoperitoneal shunt in communicating hydrocephalus patients: a pilot study
- Author
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Jong Woo Chung, Doo Sik Kong, Young Hyun Cho, Jeong Hoon Kim, Chan Joo Yang, Hyun Woo Lim, Yang Sun Cho, Byoung Soo Shim, Jung Ho Han, and Ja Won Koo
- Subjects
Adult ,Male ,Hearing loss ,Pilot Projects ,Ventriculoperitoneal Shunt ,Cochlear Aqueduct ,Cerebrospinal fluid ,otorhinolaryngologic diseases ,medicine ,Humans ,Prospective Studies ,Endolymphatic hydrops ,Hearing Loss ,Aged ,Aged, 80 and over ,business.industry ,Organ Size ,Electrocochleography ,Middle Aged ,medicine.disease ,Perilymph ,Hydrocephalus ,medicine.anatomical_structure ,Otorhinolaryngology ,Anesthesia ,Cochlear aqueduct ,Female ,sense organs ,medicine.symptom ,business ,Shunt (electrical) - Abstract
Objectives/Hypothesis Hearing loss can be associated with a decrease in cerebrospinal fluid (CSF) pressure because changes in CSF pressure induce changes in perilymph pressure. Hearing loss after neurosurgical procedures have been reported, but clinical information on hearing loss after the placement of ventriculoperitoneal (VP) shunts, the most commonly used CSF shunt for hydrocephalus patients, is limited. This study is aimed to show the relationship between VP shunt and hearing loss. Study Design Prospective study. Methods Pure tone threshold and electrocochleography were preoperatively performed in nine patients (18 ears) undergoing elective VP shunt placement. Five-day and 1-month post-shunt placement hearing thresholds were compared with baseline data. A correlation analysis was conducted between the threshold and summating potential/action potential (SP/AP) ratio changes at 5 days and 1 month after shunt placement. Cochlear aqueduct dimensions measured by high-resolution CT were compared between ears with and without hearing loss. Results About 40% of subject ears showed hearing loss with a threshold elevation of at least 15 dB in one or more frequencies. After VP shunt placement, the mean threshold of all ears showed a significant increase in most frequencies and the pure tone average. The change in the SP/AP ratios was significantly correlated with the change in the pure tone average at both 5 days and 1 month after shunt placement. Cochlear aqueduct dimensions were not correlated with hearing loss occurrence. Conclusions Hearing thresholds may increase following VP shunt placement, possibly due to secondary endolymphatic hydrops. Level of Evidence 4. Laryngoscope, 124:1923–1927, 2014
- Published
- 2013
38. Frontal transcortical approach in 12 central neurocytomas
- Author
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Sang Joon Kim, Young Hyun Cho, Shin Kwang Khang, Jeong Hoon Kim, Chang Jin Kim, and Eun Suk Park
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Neurosurgical Procedures ,Young Adult ,medicine ,Central neurocytoma ,Humans ,Neurocytoma ,Radical surgery ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Brain Neoplasms ,Interventional radiology ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Surgery ,Radiation therapy ,Hemiparesis ,Treatment Outcome ,Subdural hygroma ,Female ,Neurology (clinical) ,Neurosurgery ,medicine.symptom ,Neoplasm Recurrence, Local ,business ,Follow-Up Studies - Abstract
Central neurocytomas (CN) are rare intraventricular tumors with benign clinical behavior that typically affect young adults. Although a favorable prognosis is generally expected after adequate management, there is no general consensus on the standard of therapy. We evaluated the efficacy and safety of radical surgery for the management of CN. Between 1996 and 2010, 12 patients with CN (eight males and four females; range, 18 to 62 years; mean age, 28.5 years) were surgically treated in our institution. The initial goal of therapy was complete resection through a frontal transcortical approach, and repeat surgery was done in cases of residual or recurrent disease. The mean follow-up period was 51.2 months (range, 14–149 months). Complete resection was achieved in all patients either with primary (nine patients, 75 %) or second-look surgery (three patients, 25 %). No mortalities occurred and there were four surgery-related complications (two events of transient hemiparesis, one transient aphasia, and onepostoperative subdural hygroma). All patients were alive with normal activities of daily living at the last follow-up. Two patients (16.6 %) experienced a single recurrence at 26 and 66 months, one of whom underwent redo-surgery. For the management of CN, complete resection is feasible, effective, and safe. Repeat surgery may be a viable option in cases of residual or recurrent disease and the use of radiotherapy can be avoided in this young population.
- Published
- 2012
39. Abducens nerve schwannoma: case report and review of the literature
- Author
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Jin Hoon Park, Chang Jin Kim, J.C. Lee, Jeong Hoon Kim, and Young Hyun Cho
- Subjects
Adult ,Male ,Schwannoma ,Neurosurgical Procedures ,Vestibulocochlear nerve ,Diplopia ,Medicine ,Humans ,Abducens nerve ,Paresis ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,Anatomy ,medicine.disease ,Cerebellopontine angle ,Magnetic Resonance Imaging ,Surgery ,Neurology (clinical) ,medicine.symptom ,Differential diagnosis ,business ,Tomography, X-Ray Computed ,Neurilemmoma ,Abducens Nerve Diseases - Abstract
Schwannomas of the abducens nerve are extremely rare. The authors report a case with this tumor and discuss its clinical and radiographic characteristics. A 36-year-old man presented with 6-month history of diplopia. Right abducens nerve paresis was noted on neurologic examination. Magnetic resonance imaging revealed a 4-cm sized heterogeneously enhancing mass in the right cerebellopontine angle. Although schwannoma was suggested, no direct radiographic evidences regarding its origin were identified. Instead, the facial and vestibulocochlear nerve complex was found to be displaced posteriorly by the tumor on MR three-dimensional T2-weighted driven equilibrium sequence. Resection of the tumor was carried out via retrosigmoid approach. As the encapsulated partially suckable yellowish tumor was debulked and dissected, the abducens nerve was found to fan along and be attached to the medial surface of the tumor, which was cut at this point. Complete excision of the tumor was accomplished, and reanimation of the nerve was done by end-to-end anastomosis. Histologic feature was typical of schwannoma. Abducens schwannoma, although rare, should be taken into account for differential diagnosis of the cerebellopontine angle tumors. Appreciation of the characteristic clinical and radiographic features may provide an accurate preoperative diagnosis.
- Published
- 2008
40. Efficacy and safety of cabergoline as first line treatment for invasive giant prolactinoma
- Author
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Eun Hee Cho, Min-Seon Kim, Eun Hee Koh, Jeong Hoon Kim, Sang Ah Lee, Young Hyun Cho, Ji Youn Chung, and Chang Jin Kim
- Subjects
Adult ,Male ,medicine.medical_specialty ,Cabergoline ,Invasive Giant Prolactinoma ,Urology ,Antineoplastic Agents ,Pituitary neoplasm ,Serum prolactin ,Internal medicine ,medicine ,Humans ,In patient ,Pituitary Neoplasms ,Prolactinoma ,Tumor Size ,Ergolines ,Retrospective Studies ,Tumor size ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Prolactin ,First line treatment ,Endocrinology ,Original Article ,business ,medicine.drug - Abstract
Although cabergoline is effective in the treatment of micro- and macro-prolactinoma, little is known about its efficacy in the treatment of invasive giant prolactinoma. We investigated the efficacy and safety of cabergoline in 10 male patients with invasive giant prolactinoma. Before treatment, mean serum prolactin level was 11,426 ng/mL (range, 1,450-33,200 ng/mL) and mean maximum tumor diameter was 51 mm (range, 40-77 mm). Three months after initiation of cabergoline treatment, serum prolactin concentrations decreased more than 97% in 9 patients; at last follow-up (mean treatment duration, 19 months), the mean decrease in serum prolactin concentrations was 98%, with 5 patients having normal serum prolactin levels. At first MRI follow-up (3-12 months after initiation of cabergoline), the mean reduction in tumor size was 85+/-4% (range, 57-98%). Cabergoline treatment for more than 12 months caused a greater reduction in tumor size compared to the treatment for less than 12 months (97+/-1% vs. 78+/-7%, P0.05). These findings indicate that cabergoline treatment led to a significant and rapid reduction in serum prolactin concentrations and tumor size in patients with giant prolactinoma. Therefore, cabergoline represents an effective and well-tolerated treatment for invasive giant prolactinoma.
- Published
- 2008
41. Chordomas and chondrosarcomas of the skull base: comparative analysis of clinical results in 30 patients
- Author
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Chang Jin Kim, Jeong Hoon Kim, J.C. Lee, Young Hyun Cho, and Shin Kwang Khang
- Subjects
musculoskeletal diseases ,Adult ,Male ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Chondrosarcoma ,Skull Base Neoplasms ,Chordoma ,Medicine ,Humans ,Child ,Pathological ,Survival rate ,Aged ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Radiation therapy ,Skull ,medicine.anatomical_structure ,Treatment Outcome ,Child, Preschool ,Female ,Neurology (clinical) ,Neurosurgery ,business ,Tomography, X-Ray Computed ,Progressive disease - Abstract
Chordomas and chondrosarcomas occur rarely in the skull base and have been often considered commonly with respect to the management. The aim of this study was to investigate the clinical results in each series of these tumors and analyze comparative outcome. Between 1991 and 2005, 30 consecutive patients with pathological diagnosis of chordoma (n = 19) or chondrosarcoma (n = 11) of the skull base were managed by multimodal treatment combining surgical resection with conventional photon radiotherapy and/or gamma knife radiosurgery. A retrospective analysis was conducted on these patients (aged 3 to 69 years; mean age of 37.3 years; 17 females and 13 males; mean follow-up of 56.1 months). Four deaths occurred among the patients with chordoma. The progression-free survival rate at 3 and 5 years was 61.5 and 40.0% in chordoma. In contrast, no mortalities were observed, and there was only one recurrence among the patients with chondrosarcoma. The progression-free survival rate at 3 and 5 years was 88.9 and 80.0% in chondrosarcoma. Among 15 survivors with chordoma, four patients were suffering from severe disability with progressive disease. On the other hand, most patients with chondrosarcoma harbored stable disease and less disabling symptoms except one instance of recurrence. As the biological behavior of chordoma is much more aggressive than that of chondrosarcoma in the skull base, one should make a distinction between these entities to plan an optimal treatment strategy.
- Published
- 2007
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