Efficacy of 8 Gy Single Fraction Palliative Radiation Therapy in Painful Bone Metastases: A Single Institution Experience.

Introduction Bone metastasis (BM) is a major complication of many solid tumors like breast, prostate, lung and renal cancers. BM leads to serious sequelae of pain, fractures, spinal cord compression and hypercalcemia. Radiotherapy has an established role in relieving pain caused by BM. Worldwide different radiotherapy schedules are being used for BM. The aim of this study is to determine the efficacy of single fraction palliative radiotherapy for painful bone metastases. Methods Between April 2014 and April 2017, single fraction radiotherapy was used to treat 73 patients in our institution. They had pathologically proven breast, prostate, lung or renal cancer with radiological evidence of bone metastases. There were 39 males (53%) and 34 females (47%). The median age was 58 years (range 33-87 years). 39% patients (n = 28) had breast cancer, 35% had prostate cancer (n = 26), 23% had lung cancer (n = 17), and 3% had renal cancer (n = 2). On presentation, all the patients had a pain score of more than five on Brief Pain Inventory (BPI). Results Response assessment to pain after three months from single fraction radiotherapy was found to be complete response (CR) in 23% patients (n = 17), partial response (PR) in 38% patients (n = 28), stable disease (SD) in 26% patients (n = 19) and progressive disease (PD) in 12% patients (n = 9). The overall efficacy of treatment was 62%, with CR 23% and PR 38%. Pre-treatment mean pain score was 8.15 compared to 4.68 post-treatment (p < 0.001). Conclusions Single fraction palliative radiotherapy of 8 Gy showed significant efficacy in painful bone metastases in our setting and merits further investigation in our population.