A Population-Based Study of Palliative Radiation Therapy for Bone Metastases in Patients Dying of Prostate Cancer

Abstract

PurposeIncreasing the survival of patients with metastatic prostate cancer (PCa) may affect the demand for palliative radiation to bone (PRTB). Our aim was to characterize the use of PRTB in patients who died of PCa in British Columbia between 2003 and 2015. Methods and MaterialsAll patients with a diagnosis of PCa who died during the study period (n = 23,260) were identified from a population-based provincial registry. Patient and treatment characteristics were analyzed. PRTB utilization rate was calculated by year and location. Survival was calculated from the first and the last course of PRTB. ResultsA total of 5701 patients died of PCa, with a median survival from diagnosis of 5.2 years. The overall PRTB utilization rate was 38.6%, with an increasing trend over time. Multiple courses of PRTB were frequent, with 51% of patients receiving ≥2 courses of PRTB. Of the patients who died of PCa (15.2% of the PRTB cohort), 5.4% received PRTB within the last 4 weeks of life, 60% of whom received multiple fractions. Rural areas had a lower referral rate and lower use of PRTB. Patients with longer survival tended to receive multiple courses of treatment. The median survival after the first course of PRTB increased from 8.2 months in 2003 to 2004 to 9.4 months in 2013 to 2014 (P = .04). ConclusionsPRTB is only used in a minority of patients dying of PCa. The majority who die of PCa after PRTB do so within a year of their first course. The use of multifractionation was common in the last 4 weeks of life. Survival after first PRTB increased minimally over time, and additional research is required to identify its association with recent changes in practice. The referral rate and PRTB utilization rate differ between rural and nonrural locations, underlying the importance of accessibility and referral for utilization of PRTB. Investigating other barriers and ensuring equitable access to radiation are needed.