EPID-27GLIOSTRY (GLIOBLASTOMA REGISTRY) OF THE AINO (ITALIAN ASSOCIATION OF NEURO-ONCOLOGY): ANALYSIS OF FACTORS INFLUENCING SURVIVAL IN GLIOBLASTOMA PATIENTS RECEIVING THE NITROSOUREA FOTEMUSTINE AT FIRST PROGRESSION FOLLOWING THE STUPP REGIMEN

BACKGROUND: Patients with glioblastoma at first progression after standard radiotherapy and temozolomide often receive nitrosoureas, but factors influencing survival following treatment with these drugs are not well known. We investigated a large cohort of glioblastoma patients who received the nitrosourea fotemustine (FTM) at first progression following the Stupp regimen. METHODS: Survival data and information on demographics, clinical, radiological, pathological, molecular and treatments factors were collected in 34 Italian Institutions. PFS and OS curves were drawn using the Kaplan-Meier method and both univariate and multivariate analysis were performed. RESULTS: Up to date 670 patients, who were enrolled between 2005 and 2012, are evaluable. Median PFS following FTM was 3.4 months. Factors correlated with PFS in univariate analysis were MGMT methylation and association of FTM with bevacizumab. Both MGMT status with an HR of 0.64 (0.52-0.79), p < 0,001, and association of FTM with bevacizumab with an HR of 0.71 (0.56-0.92), p < 0,008, remained significant after multivariate analysis. PFS was 4.3 months in methylated patients vs 3.0 months in unmethylated ones, and 4.9 months for FTM + bev vs 3.2 months for FTM alone. Median OS following FTM was 6.6 months. Factors correlated with OS in univariate analysis were age, Karnofsky Performance Score, extent of surgery, MGMT status and association of FTM with bev. MGMT status with HR of 0.60 (0.48-0.76), p < 0.001, and association of FTM with bev with HR of 0.73 (0.56-0.95), p = 0.022, remained significant after multivariate analysis. OS was 7.6 months in methylated patients vs 5.5 months in unmethylated ones, and 7.6 months for FTM + bev vs 6 months for FTM alone. CONCLUSIONS: MGMT is a factor of strong prognostic and predictive value in GBM patients treated at first progression with FTM. The association of bev with FTM could be superior over FTM alone.