Is the Duration of Temozolomide Predictive for Sequential Bevacizumab Treatment Responses in the Glioblastoma Multiforme Cancer Setting?

Objective: To evaluate the predictive significance of the duration of temozolomide (TMZ) in patients with glioblastoma multiforme (GBM) who were treated with bevacizumab (Beva) as second-line setting. Study Design: Descriptive study. Place and Duration of Study: Bezmialem Vakif University School of Medicine Hospital, Istanbul, Turkey, from January 2014 to September 2020. Methodology: A total of 109 patients, 47 (43.1%) females and 62 (56.9%) males, were retrospectively included in the study. All patients received TMZ as first-line and Beva as second-line treatment. Kaplan-Meier method and Cox regression model were performed for survival and univariate/multivariate analyses, respectively. Results: Patients treated with first-line TMZ were divided into two groups according to the PFS. Group 1 is <9 months and group 2 is >= 9 months. Overall survival (OS) of group 1 and group 2 patients was evaluated after the initiation of second-line bevacizumab treatment. The OS in group 1 was 7.8 months (6.9-8.6, 95% CI), and group 2 was eight months (6.4-9.5, 95% CI), but it was statistically non-significant (p = 0.837). Conclusion: Duration of first-line TMZ treatment was not a predictor for OS of the GBM patients, who were treated with Beva as second-line setting.