Sub-category: CNS Tumors Category: Central Nervous System Tumors
Meeting: 2006 ASCO Annual Meeting
Printer Friendly E-Mail Article Abstract No: 1511 Citation: Journal of Clinical Oncology, 2006 ASCO Annual Meeting Proceedings Part I. Vol 24, No. 18S (June 20 Supplement), 2006: 1511 Author(s): L. Buttolo, F. Giunta, V. D. Ferrari, S. Grisanti, G. Marini, P. Mortini
Abstract: Background: Temozolomide (TMZ) is an oral alkylating agent with proven efficacy in the therapy of glioblastoma multiforme (GBM). The activity of TMZ is drug-exposure dependent, however dosages are primarily limited by myelotoxicity. In the attempt to increase survival while limiting toxicity, we treated GBM patients (pts) with one of 3 alternative adjuvant TMZ schedules, including a low-dose daily regimen.
Methods: We assessed the overall survival and the development of grade 3-4 myelotoxicity in pts with GBM who were treated in our centre (November 1998-October 2005), following surgery, with one of the following TMZ schedules: standard schedule (SS: 200-300 mg/m2 × 5 days, every 28 days); extended schedule (ES: 150 mg/m2 × 7 days every 15 days); daily schedule (DS: 75 mg/m2 daily). Pts were treated until death or tumour progression. The analysis of survival was based on the Kaplan-Meier (KM) and the Cox models. Adverse events were graded according to NCICTC 3.0.
Results: We evaluated 117 pts (73 m, 44 f, avg. age 57 yrs, 53% received radiotherapy, RT) with histologically diagnosed gliomas (GBM=92.3%) treated with TMZ SS (tot pts=48, RT pts=22, no. cycles: 1÷33, avg 6) or ES (tot pts=35; RT pts=19, no. cycles: 1÷43, avg 16) or DS (tot pts=34; RT pts=21, days of treatment: 25÷671, avg 212). The overall survival significantly differed among the 3 schedules (KM), with DS providing the best outcome (p=0.0357, log-rank). Median survival time was markedly increased in DS pts (DS=29.47 months; ES=15.73 months; SS=11.90 months) as well as the survival rate at 2 yrs after diagnosis (DS=51%; ES=30%; SS=21%). DS, but not ES, significantly reduced the mortality hazard ratio (HR) compared to SS (Cox: HR=0.494; IC95% 0.253-0.966, p=0.039). Grade 3-4 myelotoxicity (leukopenia, LP; neutropenia, NP; thrombocytopenia,TP) occurred less frequently with DS (NP=2.9%; TP=2.9%; any=5.9%) than with ES (LP=11.4%; NP=14.3%; TP=17.1%; any=28.6%) and SS (LP=14.6%; NP=8.3%; TP=20.8%; any=22.9%).
Conclusions: In our experience with adjuvant TMZ in GBM, a continuous daily dose of 75 mg/m2 was on the whole more advantageous than a standard monthly or a biweekly regimen, as it resulted in the highest overall survival with the lowest hematologic toxicity.