Changes Over Time in Total Medicare Costs for Active Surveillance Versus Radiation Therapy in Prostate Cancer.

[PURPOSE] This study evaluated whether the difference in total Medicare costs between active surveillance (AS) and radiation therapy (RT) changed over time for men with low- or favorable intermediate risk prostate cancer.

[METHODS AND MATERIALS] Using Surveillance, Epidemiology, and End Results-Medicare data, we calculated the costs associated with AS versus 4 RT modalities: brachytherapy, stereotactic body RT, intensity modulated RT, and proton beam therapy. We included costs that pertained to treatment, surveillance, and morbidity management for each patient, for 3 years after diagnosis. Costs were adjusted to 2017 dollars. Multivariable models assessed whether the cost gap between AS and RT changed between patients diagnosed in 2 time periods (2010-2014 vs 2015-2019).

[RESULTS] AS costs increased over time, driven by surveillance and morbidity expenses, whereas RT costs decreased across treatment, surveillance, and morbidity. After adjusting for patient and clinical factors, the cost gap between AS and RT (all modalities combined) decreased by a mean of $3777 from the earlier to the later period. A decrease in the cost gap over time between AS versus RT was observed for all RT modalities ($607 for brachytherapy, $4408 for stereotactic body RT, $5385 for intensity modulated RT, and $3663 for proton therapy), although it was not statistically significant for brachytherapy.

[CONCLUSIONS] Although AS remains the least costly approach, the cost gap between AS and RT has decreased over time, which may be related to the intensification of AS and the deintensification of RT.