Second-line chemotherapy with irinotecan plus carmustine in glioblastoma recurrent or progressive after first-line temozolomide chemotherapy: a phase II study of the Gruppo Italiano Cooperativo di Neuro-Oncologia (GICNO)

Abstract

Purpose: Glioblastoma multiforme (GBM), the most frequent brain tumor in adults, is not considered chemosensitive. Nevertheless, there is widespread use of first-line chemotherapy, often with temozolomide, as a therapeutic option in patients with progressive disease after surgery and radiotherapy. However, at the time of second recurrence and/or progression, active and noncross-resistant chemotherapy regimens are required. The aim of the present multicenter phase II trial, therefore, was to ascertain the efficacy of second-line carmustine (BCNU) and irinotecan chemotherapy.

Patients and methods: Patients with histologically confirmed GBM, recurring or progressing after surgery, standard radiotherapy and a first-line temozolomide-based chemotherapy, were considered eligible. The primary end-point was progression-free survival at 6 months (PFS-6), and secondary end-points included response rate, toxicity, and survival. All patients were on enzyme-inducing antiepileptic prophylaxis. Chemotherapy consisted of BCNU (100 mg/m2 on day 1) plus irinotecan (175 mg/m2/weekly for 4 weeks), every 6 weeks, for a maximum of eight cycles. In the absence of grade 2 toxicity, the irinotecan dose was increased to 200 mg/m2.

Results: A total of 42 patients (median age, 53.4 years; median Karnofsky performance status, 80; range, 60 to 90) were included in the study. PFS-6 was 30.3% (95% CI, 18.5% to 49.7%). Median time to progression was 17 weeks (95% CI, 11.9 to 23.9). Nine partial responses (21.4%; 95% CI, 9% to 34%) were obtained. Toxicity was manageable.

Conclusion: The BCNU plus irinotecan regimen seems active and non-cross-resistant in patients with GBM with recurrence after temozolomide-based chemotherapy.