Survival analysis of patients with glioblastoma treated by long-term administration of temozolomide

This analysis aimed to investigate whether the long-term administration of temozolomide (TMZ) claimed a survival advantage for patients with glioblastoma in China. A total of 75 patients with newly diagnosed glioblastoma at the Department of Radiation Oncology, Shenzhen People's Hospital between August 2008 and August 2016 were retrospectively evaluated during analysis. A propensity-matched analysis was performed to balance the basic characteristics of patients between compared groups. Kaplan-Meier method and Cox proportional hazards model were used to assess progression-free survival (PFS) and overall survival (OS) of patients receiving 6 adjuvant TMZ cycles compared with patients treated with more than 6 cycles. Twenty of 75 patients received more than 6 cycles of TMZ, and the other 55 patients were treated with a median of 6 cycles ranging from 1 to 6. The patients with long-term administration of TMZ had better OS (47.0 months, 95% CI 20.0-73.9 vs 20.6 months, 95% CI 17.9-23.2, P = .014) but not PFS (17.0 months, 95% CI 10.1-24.5 vs 14.2 months, 95% CI 11.8-16.6, P = .133). Balancing the clinical factors with a propensity-matched analysis also showed the significant advantage of prolonged TMZ application in terms of OS but not PFS. Prolonged administration of TMZ beyond 6 cycles did demonstrate survival benefits for patients with initially diagnosed glioblastoma.