Comparison of Volumetric Modulated Arc Therapy and Fixed Field Intensity Modulated Radiotherapy for Radical Treatment of Early Prostate Cancer using Hypofractionated Radiotherapy

Abstract

Objective: To investigate the dosimetric advantages of volumetric modulated arc therapy over intensity-modulated radiation therapy for radical treatment of early-stage prostate cancer. Study Design: Retrospective longitudinal study. Place and Duration of Study: Department of Radiation Oncology, Combined Military Hospital, Rawalpindi Pakistan, from Jan to Jun 2019. Methodology: Two treatment plans; one volumetric modulated arc therapy and other intensity-modulated radiation therapy, were made for 13 patients undergoing radical radiotherapy for early prostate cancer. Conformity index, Homogeneity index, the volume of rectum and bladder receiving a dose of 50 Gy or more, monitor units employed and treatment delivery time were compared between both techniques. Results: Volumetric modulated arc therapy plans showed statistically better conformity index and Homogeneity index with significantly lower doses to the rectum and bladder than intensity-modulated radiation therapy plans. The number of monitor units (MUs) employed and treatment delivery time were also reduced significantly with volumetric modulated arc therapy. Conclusion: Volumetric modulated arc therapy generates dose-metrically better radiotherapy plans than intensity-modulated radiation therapy and can deliver the required dose faster. Keywords: Hypofractionated radiotherapy, Intensity-modulated radiation therapy, Prostate cancer, Volumetric modulated arc therapy.

Keywords

• Hypofractionated radiotherapy
• Intensity-modulated radiation therapy
• Prostate cancer
• Volumetric modulated arc therapy