142PD Reirradiation for Glioblastoma with Temozolomide: Delicate Balance Between Effectiveness and Toxicity

Background The outcome of patients with recurrent glioblastoma is dismal despite the use of multimodality treatment. To asses the efficacy of high precision reirradiation with temozolomide as a salvage in patients with recurrent Glioblastoma. Methods A retrospective analysis was performed on 25 patients of recurrent glioblastoma, reirradiated with concurrent temozolomide between 2010 to 2015. All treatment decisions were based on interdisciplinary meeting. Survival time was calculated using the Kaplan-Meier method. Univariate and multivariate analysis were done using cox regression method. Characteristics of the 25 patients diagnosed were as follows: 18 men, 7 women; median age, 52 years (range, 20-65). At recurrence, 12 patients underwent both surgery and reirradiation, while 13 patients underwent radiation only. During reirradiation, 2 patient received stereotactic radiosurgery; 14 hypofractionated stereotactic radiation therapy (15-40 Gy in 3-5 fractions); 9 conventionally fractionated stereotactic radiation therapy (45-54 Gy in 25-27 fractions). All patient received temozolomide (either adjuvant or concurrent followed by adjuvant). 7 patient had MGMT methylated while 8 patient had non methylated tumours. Results At the time of recurrence, median Karnofsky Performance Score (KPS) was 70% (range, 40-90). Median follow-up from recurrence was 12 months (range, 1-47.8 months). Median overall survival (OS) from recurrence was 15.26 months (95% confidence interval [CI], 10-20.33 months). None of the factor analysed (age, sex, gross tumour volume at time of recurrence, KPS, MGMT, time of recurrence) were significant for outcomes. No grade III or above acute or late complications arose due to reirradiation, and all patients completed planned course of radiation therapy. Conclusions Our results suggest that reirradiation with high precision radiotherapy along with temozolamide is an effective option in patients with recurrent glioblastoma. Legal entity responsible for the study Medanta The Medicity Funding N/A Disclosure All authors have declared no conflicts of interest.