OBJECTIVETo study the function of radiosurgery on malignant glioma by analyzing prognostic factors affecting malignant gliomas treated with linac radiosurgery.

METHODFifty-eight patients with deep situated malignant gliomas, aged 7 to 70 years, 28 anaplastic astrocytomas and 30 glioblastomas multiforme were analyzed. The median volume of tumor was 10.67 cm3, and median prescription dose for linac radiosurgery was 20 Gy. Results were analyzed with Kaplan-Meier curve and Cox regression.

RESULTIn follow-up 44.8 percent tumors (26 patients) decreased in size. Median tumor local control interval was 10 months, 15 months for anaplastic astrocytomas, and 9 months for glioblastoma multiforme. Tumor local control probability was 37.9 percent for 1 year and 10.3 percent for 2 years. Median survival was 22.5 months for anaplastic astrocytoma, 13 months for glioblastoma multiforme, and 15 months for all patients. The survival probability was 79.3 percent at 1 year and 20.6 percent at 2 years. Isocenter numbers and tumor volume were the prognostic factors for tumor control, but conformity index was the prognostic factor for survival by Cox regression analysis. Considering pathology, only isocenter number and target volume significantly affected tumor control interval. Complications appeared in 44.8 percent patients and the median interval of complication onset was 8 months. Symptomatic cerebral edema was observed in 31.0 percent patients.

CONCLUSIONLinac radiosurgery can effectively improve tumor local control and prolong survival for deep situated malignant gliomas.

Adolescent ; Adult ; Aged ; Astrocytoma ; mortality ; pathology ; surgery ; Brain Neoplasms ; mortality ; pathology ; surgery ; Child ; Female ; Follow-Up Studies ; Glioblastoma ; mortality ; pathology ; surgery ; Humans ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; Prognosis ; Radiosurgery ; Survival Rate

OBJECTIVE: To determine whether pre-operative perfusion skewness and kurtosis derived from normalized cerebral blood volume (nCBV) histograms are associated with progression-free survival (PFS) of patients after partial resection of newly diagnosed glioblastoma. MATERIALS AND METHODS: A total of 135 glioblastoma patients who had undergone partial resection of tumor (resection of < 50% of pre-operative tumor volume or surgical biopsy) confirmed with immediate postsurgical MRI and examined with both conventional MRI and dynamic susceptibility contrast (DSC) perfusion MRI before the surgery were retrospectively reviewed in this study. They had been followed up post-surgical chemoradiotherapy for tumor progression. Using histogram analyses of nCBV derived from pre-operative DSC perfusion MRI, patients were sub-classified into the following four groups: positive skewness and leptokurtosis (group 1); positive skewness and platykurtosis (group 2); negative skewness and leptokurtosis (group 3); negative skewness and platykurtosis (group 4). Kaplan-Meier analysis and multivariable Cox proportional hazards regression analysis were performed to determine whether clinical and imaging covariates were associated with PFS or overall survival (OS) of these patients. RESULTS: According to the Kaplan-Meier method, median PFS of group 1, 2, 3, and 4 was 62, 51, 39, and 41 weeks, respectively, with median OS of 82, 77, 77, and 72 weeks, respectively. In multivariable analyses with Cox proportional hazards regression, pre-operative skewness/kurtosis pattern (hazard ratio: 2.98 to 4.64; p < 0.001), Karnofsky performance scale score (hazard ratio: 1.04; p = 0.003), and post-operative tumor volume (hazard ratio: 1.04; p = 0.02) were independently associated with PFS but not with OS. CONCLUSION: Higher skewness and kurtosis of nCBV histogram before surgery were associated with longer PFS in patients with newly diagnosed glioblastoma after partial tumor resection.
Adult ; Aged ; Aged, 80 and over ; Brain Neoplasms/*mortality/pathology/*surgery ; Chemoradiotherapy ; Disease-Free Survival ; Female ; Glioblastoma/*mortality/pathology/*surgery ; Humans ; Image Interpretation, Computer-Assisted ; Image Processing, Computer-Assisted ; Kaplan-Meier Estimate ; Magnetic Resonance Imaging/methods ; Male ; Middle Aged ; Regression Analysis ; Retrospective Studies ; Statistical Distributions ; Tumor Burden ; Young Adult