Trends in Utilization and Medicare Spending on Short-Course Radiation Therapy for Breast and Prostate Cancer: An Episode-Based Analysis From 2015 to 2019.

Purpose: Evidence supports the value of shorter, similarly efficacious, and potentially more cost-effective hypofractionated radiation therapy (RT) regimens in many clinical scenarios for breast cancer (BC) and prostate cancer (PC). However, practice patterns vary considerably. We used the most recent Centers for Medicare and Medicaid Services data to assess trends in RT cost and practice patterns among episodes of BC and PC.

Methods And Materials: We performed a retrospective cohort analysis of all external beam RT episodes for BC and PC from 2015 to 2019 to assess predictors of short-course RT (SCRT) use and calculated spending differences. Multivariable logistic regression defined adjusted odds ratios of receipt of SCRT over longer-course RT (LCRT) by treatment modality, age, year of diagnosis, type of practice, and the interaction between year and treatment setting. Medicare spending was evaluated using multivariable linear regression controlling for duration of RT regimen (SCRT vs LCRT) in addition to the above covariables.

Results: Of 143,729 BC episodes and 114,214 PC episodes, 63,623 (44.27%) and 25,955 (22.72%) were SCRT regimens, respectively. Median total spending for SCRT regimens among BC episodes was $9418 (interquartile range [IQR], $7966-$10,983) versus $13,602 (IQR, $11,814-$15,499) for LCRT. Among PC episodes, median total spending was $6924 (IQR, $4,509-$12,905) for stereotactic body RT, $18,768 (IQR, $15,421-$20,740) for moderate hypofractionation, and $27,319 (IQR, $25,446-$29,421) for LCRT. On logistic regression, receipt of SCRT was associated with older age among both BC and PC episodes as well as treatment at hospital-affiliated over freestanding sites (P < .001 for all).

Conclusions: In this evaluation of BC and PC RT episodes from 2015 to 2019, we found that shorter-course RT resulted in lower costs than longer-course RT. SCRT was also more common in hospital-affiliated sites. Future research focusing on potential payment incentives encouraging SCRT when clinically appropriate in the 2 most common cancers treated with RT will be valuable as the field continues to prospectively evaluate cost-effective hypofractionation in other disease sites.