Impact of intense systemic therapy and improved survival on the use of palliative radiotherapy in patients with bone metastases from prostate cancer

Abstract

More effective drugs may reduce the requirement for palliative external beam radiotherapy for bony target volumes; however, living with metastases for prolonged periods of time may result in more frequent episodes of bone pain or serious skeletal-related events. The purpose of the present study was to evaluate how recent advances in systemic therapy impact radiotherapy utilization. A retrospective analysis of a comprehensive regional database was performed. All oncology care in this region was provided by only one center, assuring complete data. Patients that had succumbed between June 1, 2004 and June 1, 2015 were included. For all 236 patients, the median age at diagnosis of bone metastases was 75 years and median overall survival was 20 months. More intense systemic therapy was associated with a significantly longer survival time. Only 69 patients (29%) did not receive palliative radiotherapy for bony target volumes, whilst 1 course was given to 101 patients (43%), 2 courses to 34 patients (14%) and >2 courses to 32 patients (14%). Radiotherapy was used more frequently in younger patients, those with spinal cord compressions or pathological fractures, and those treated with intense and long-standing systemic therapy. Radiotherapy utilization increased with survival time. For 100 poor-prognosis patients that succumbed within 12 months, 57 courses of palliative radiotherapy were administered, whilst 100 patients that survived for 12-24 months were administered 114 courses (24-36 months, 148 courses). In conclusion, the use of palliative radiotherapy did not decrease when more effective systemic therapy was administered. However, provided that only 5% of patients received radionuclide treatment, additional studies in other populations are required.