Fractionated Stereotactic Sequential Boost in a Selected Cohort of Glioblastoma Patients: A Mono-institutional Analysis

Aim: To retrospectively assess toxicity and survival in 15 selected Glioblastoma patients treated with a sequential fractionated stereotactic radiotherapy (FSRT) boost after chemo-radiotherapy (CHT-RT) and compare their survival outcomes with a control group.

Patients and methods: Toxicity was assessed with the CTCAE 3.0 scale. The Kaplan-Meier method was used to design survival curves, log-rank test for bivariate analysis and Cox proportional hazard regression model for multivariate analysis.

Results: The median follow-up was 16 months (range=5-60). One case of headache and one of radionecrosis (RN) occurred. Median overall survival (OS) was 25 months in the boost group vs. 14 in the no-boost group (p=0.004). Median progression-free survival (PFS) was 15 months in the boost group versus 8 in the no-boost group (p=0.046). At multivariate analysis FSRT boost resulted significantly associated with OS and PFS.

Conclusion: In our series a sequential FSRT boost resulted in safe outcomes and significantly associated with survival.

Keywords: Glioblastoma; boost; fractionated stereotactic radiotherapy; survival; toxicity.