“Radiotherapy plus Concomitant and Adjuvant Temozolomide for Glioblastoma”

Adding concomitant and adjuvant temozolomide to radiotherapy when treating adult glioblastoma significantly increases survival, this study found. A total of 573 patients newly diagnosed with glioblastoma, aged 18 to 70, were randomized to receive standard focal radiotherapy (286 patients) or radiotherapy plus concomitant daily temozolomide, followed by adjuvant temozolomide (287 patients). At a median follow-up of 28 months, 84% of patients (480) had died. However, there was a 37% relative reduction in the risk of death in the temozolomide group, with a median survival benefit of 2.5 months. The two-year survival rate for the temozolomide group was 26.5%, versus 10.4% in the radiotherapy group. Event-free survival was also improved, at a median of 6.9 months for the temozolomide group and 5.0 moths for the radiotherapy group. Grade 3 or 4 hematologic toxic events occurred in 7% of radiotherapy-plus-temozolomide patients, whereas none occurred in the radiotherapy group. In an accompanying editorial, Lisa M. DeAngelis, MD, Chair of the Department of Neurology and Chief of the Neurology Service at Memorial Sloan-Kettering Cancer Center, speculates as to why this study showed a larger benefit from adding temozolomide to glioblastoma treatment than all previous studies. First, the patients in this study were relatively healthy; second, temozolomide is less toxic and may be more effective than the nitrosourea drugs previously used as adjuvant therapy; and third, the novel use of concomitant temozolomide may have improved outcomes. “The minimal toxicity associated with temozolomide and the clear benefit of its use make it reasonable to give this drug to all patients [with newly diagnosed glioblastoma] now,” she writes. However, she agrees with the study's authors that more research is needed before this treatment can be recommended for patients with lower-grade gliomas.