Utilization Patterns of Single-Fraction and Short-Course Radiotherapeutic Schedules in the Management of Bone Metastases

Abstract

Purpose: Bone metastases are common, occurring in 60% to 70% of patients with advanced malignancies. Historically, bone-directed radiation therapy regimens of 30 Gy over 10 fractions were used. However, prospective randomized data suggest equivalent pain relief with shorter-course regimens. The American Society for Radiation Oncology Choosing Wisely Campaign encourages clinicians to consider shorter-course palliative regimens in patients with limited prognosis. A retrospective analysis was performed to assess patterns of short-course and single-fraction radiation therapy during the past 5 years. Methods and Materials: We queried our electronic medical record (MOSAIQ) from 2016 to 2020 for patients with bone metastases who received palliative radiation therapy. Patients receiving >10 fractions or Medicare-approved palliative courses of radiation (30 Gy/10 fractions, 24 Gy/6 fractions, 20 Gy/5 fractions, 8 Gy/1 fraction) were included. Treatment department was defined as academic (n = 2) versus community (n = 12). Short-course treatment was defined as 10 fractions. Patients were subdivided based on age and disease site. Physicians were grouped according to their year of residency completion. Multivariable logistic regression analysis identified predictors of short-course and single-fraction treatment. Results: We identified 1004 patients with 1768 bony metastases meeting inclusion criteria. The spine was the most common site, followed by pelvis/hip, extremity, and other site. Use of short-course treatment increased from 40% in 2016 to 50% in 2020. Single-fraction treatment increased from 7% in 2016 to 11% in 2020. Predictors of shorter courses included treatment at academic centers, more recent treatment, patient age >76 years, and nonspine anatomic site. Predictors of single-fraction treatment included treatment at academic centers, treating physician residency completion after 2010, patient age >76 years, and treatment to extremity or other site. Conclusions: Rates of short-course and single-fraction bone-directed radiation therapy increased within our health system over time. Treatment receipt at academic centers was associated with both short-course and single-fraction regimens. Physicians completing residency after 2010 were more likely to deliver single-fraction therapy.