Early Results of Simultaneous Integrated Boost Volumetric Modulated arc Therapy (SIB-VMAT) Combined with Temozolomide in the Postoperative Treatment of Grade 4 glioblastoma

Abstract

Introduction. Glioblastoma refers to a neuroepithelial malignant brain tumor with an aggressive course and extremely unfavorable prognosis. The median overall survival comprises 14.6 months. Standard treatment demonstrates relatively poor efficiency due to high recurrence rate associated with the high repopulation rate of tumor cells as well as impossibility of eradication of primary tumor. Simultaneous integrated boost is recognized as a technique to enhance local control in gliomas. Materials and methods. The study analyzed data of 25 patients who received chemoradiotherapy for grade 4 glioblastoma in the Radiotherapy Unit No 1. Day hospital lasted from September 2021 to March 2023 (data were analyzed over a year). In group 1, 15 patients received chemoradiation treatment, including simultaneous integrated boost volumetric modulated arc therapy (SIB-VMAT). In group 2, 10 patients received standard fractionated radiation therapy. Results and discussion. Treatment tolerability appeared satisfactory: the target dose was administered in 100% of patients without forced interruptions, toxicity was comparable in both groups; 1-year locoregional control comprised 46.7% in the group with simultaneous integrated boost, 50% in the group of standard fractionated therapy; 1-year overall survival accounted for 66.7% in the group with simultaneous integrated boost, and 70% in the group of standard therapy. The follow-up period revealed no cases of radiation necrosis. The results obtained in the present study appear comparable with the data of relevant scientific publications on the issue. Conclusion. Radiation therapy using simultaneous integrated boost in the postoperative treatment of grade 4 glioblastoma is considered as an acceptable and safe method with moderate toxicity and satisfactory overall survival rate.