SUPRATENTORIAL MALIGNANT GLIOMAS - RESULTS IN 280 CASES TREATED BY POSTOPERATIVE RADIOTHERAPY

Background - This retrospective study intended, firstly, to examine th e prognostic significance of the classification of malignant glioma in to glioblastoma multiforme (GBM) and anaplastic astrocytoma (AA), and secondly, to analyze the influence of some well known prognostic facto rs according to Cox proportional hazard model. Methods - 280 adult pat ients between 16 and 75 years of age with supratentorial malignant gli oma, who underwent surgery and post-operative radiotherapy between 196 4 and 1990, were periodically followed up until death or for at least 18 months. All pathological specimens were reviewed and glioblastoma m ultiforme (GBM) was distinguished from anaplastic astrocytoma (AA) by the presence of necrosis. Results - the median survival time (MST) was 17 months for the 114 patients with AA compared with 10.5 months for the 166 patients with GBM; 2- and 5-year overall survival was 41 % and 21 % for AA patients and 13 % and 0 % for GBM patients (p=0.0001) res pectively. According to the Cox proportional hazard model for AA patie nts, age (p=0.0001), Karnofsky performance status (KPS) (p=0.0004), ex tensive or non-extensive resection (p=0.024) were significant factors in prognosis, while only the different periods of treatment (1964-1979 vs 1980-1990) (p=0.0001) and KPS (p=0.0024) were significant factors for GBM patients. Conclusions - this study demonstrates that the class ification into AA and GBM affects prognosis and that these two types o f malignant glioma must be analyzed separately. Age, KPS, extent of su rgery and improvement in imaging and therapy had different prognostic importance for AA and GBM patients.