425P - The Role of Temozolomide and Radiation Therapy in Elderly Patients with Glioblastoma: a Monoinstitutional Retrospective Study

Abstract

ABSTRACT Aim: The efficacy of temozolomide(TMZ) plus radiation therapy(RT) in elderly patients(EP) with glioblastoma(GBM) is unclear. We describe our experience of combining RT with concurrent TMZ in EP. Methods: Medical records of patients ≥65 years old with newly GBM, histologically confirmed and treated at Venetian Institute of Oncology – Padua, were reviewed. Concomitant TMZ was 75mg/m2/die. The adjuvant treatment consisted of TMZ 150-200mg/m2/die for six cycles. Results: We analyzed 67 consecutive patients(PTS), 35 males and 32 females; the average age was 71 (range 65-86); ECOG PS was 0-1 in 37 PTS and 2-3 in 30 PTS; complete surgery was performed in 41 PTS, partial surgery in 24 PTS. MGMT was analyzed in 46 PTS: methylated(met) MGMT in 21 PTS (46%). 36 PTS were treated with RT 40Gy in 15 fractions, 23 PTS with RT 60Gy in 30 fractions, 8 PTS with only TMZ. For all PTS, PFS and OS was 7 and 12.4 ms, respectively. PFS was 7.2 vs 6.7 ms (p = 0.5), OS was 11.9 vs 13.8 ms (p = 0.3), for PTS treated with RT 40Gy and 60Gy, respectively. PFS was 7.2 vs 4.5 ms (p = 0.04), OS was 13 vs 7.3 ms (p Conclusions: RT plus TMZ is effective and safe in EP with GBM. RT + TMZ treatment seems more effective than only TMZ. PFS and OS were not statistically different between RT 40Gy or 60Gy. RT + TMZ treatment and met MGMT were independent predictors of longer survival. In contrast, severe haematological toxicity was higher in PTS with RT + TMZ compared to TMZ alone. Disclosure: All authors have declared no conflicts of interest.