P17.31 * LONG-TERM SURVIVAL OF GLIOBLASTOMA PATIENTS: WHICH CLINICAL AND MOLECULAR CORRELATION?

Abstract

BACKGROUND: Long-term survivors of glioblastoma (GBM) are rare. Patients with GBM have a median survival of less than 1 year. About 4% of patients survive beyond 3 years. Several variables besides tumor size and location determine a patient's survival chances: age at diagnosis, where younger patients often receive more aggressive treatment that is multimodal; functional status, which has a significant negative correlation with age; histologic and genetic markers. METHODS: Despite extensive clinical trials, prediction of clinical outcome for individual patients has remained an elusive goal. In search of factors or predictors of long-term survival, we conducted a retrospective analysis of GBM patient with a survival beyond 30 months in order to evaluate clinical and molecolar prognostic factors. Kaplan-Meier method was applied to estimate time to relapse and survival. The log-rank test was used to compare subgroups. RESULTS: A total of 27 GBM patients were studied. Twenty out of 27 (74%) were males. Median age was 53 years (29-74 years). Twenty-five (93%) patients had a total resection. All patients but one were received radiotherapy combined to Temozolomide (TMZ) as early treatment followed by a median cycle of TMZ of 16 months (1-53 months). The median number of previous chemotherapy lines was 2 (0-4) and 13 (48%) patients received second surgery for relapsed disease. Information about MGMT methylation was, to date, available for 13 patients out of 27 (48%) and 10 out of these were methylated. A median time of first relapsed was 21 months (95% confidence interval (95%CI: 13-28 months). Median survival was 40 months (95%CI: 35-44 months). Better survival was showed in patients younger at diagnosis (< 50 years) (p = 0.028) and in patients who were able to receive more than two lines of treatment (p < 0.0001). CONCLUSIONS: The study confirms, in an homogenous series of patients, that positive clinical prognostic factors for increased survival of GBM patients are the age and more than one previous chemotherapy. These finding has a major impact on clinical practice, as an incentive to treat patients beyond the first line when they have the appropriate clinical conditions. Molecular correlations (MGMT, IDH1) with long-survival will be presented to the meeting.