Fotemustine as second-line treatment for recurrent or progressive glioblastoma after concomitant and/or adjuvant temozolomide: a phase II trial of Gruppo Italiano Cooperativo di Neuro-Oncologia (GICNO)

Background Standardized salvage treatment has not yet proved effective in glioblastoma multiforme (GBM) patients who receive prior standard radiotherapy plus concomitant and adjuvant temozolomide. Methods Patients with progressive GBM after radiotherapy plus concomitant and/or adjuvant temozolomide received three-weekly doses (100–75 mg m2) of fotemustine followed, after a 5-week rest, by fotemustine (100 mg m2) every 3 weeks for ≤1 year. Results Forty-three patients (29 M, 14 F; median age 51 years, range 34–68; median KPS 90) were enrolled. Progression-free survival at 6 months (PFS-6) was 20.9% (95% CI: 9–33%); three patients (7.1%) had partial response (PR); 15 (34.9%), disease stabilization (SD). The median survival was 6 months (95% CI: 5–7). MGMT promoter status was methylated in 8 (18.6%) and unmethylated in 26 (60.5%) and not assessable in 9 (20.9%) patients, respectively. Disease control was 75% versus 34.6% in methylated and unmethylated MGMT patients (P = 0.044); no significant difference was found between groups for PFS-6 and survival. Grade 3 and 4 thrombocytopenia and neutropenia were observed in 20.9 and 16.3% of patients, during the induction phase, and in 0 and 9.5% patients during the maintenance phase, respectively. Conclusions The findings of the present trial, that evaluate fotemustine in a homogeneous population, may represent a new benchmark for nitrosourea activity. Moreover, this is the first study to evaluate correlation between MGMT promoter status and outcome of fotemustine for relapsing GBM previously treated with radiotherapy and temozolomide.