Patient-reported Quality of Life After SBRT, LDR, and HDR Brachytherapy for Prostate Cancer: A Comparison of Outcomes.

PURPOSE: We sought to compare changes in patient-reported quality of life (PRQOL) following stereotactic body radiation therapy (SBRT), high dose rate (HDR), and low dose rate (LDR) brachytherapy for prostate cancer. MATERIALS AND METHODS: International Prostate Symptom Score (IPSS), Sexual Health Inventory For Men (SHIM), and Expanded Prostate cancer Index Composite Short Form (EPIC-26) were prospectively collected for men with low/intermediate-risk cancer treated at a single institution. We used Generalized Estimating Equations to identify associations between variables and early (3 to 6 mo) or late (1 to 2 y) PRQOL scores. Minimally important differences (MID) were compared with assess clinical relevance. RESULTS: A total of 342 LDR, 159 HDR, and 112 SBRT patients treated from 2001 to 2018 were eligible. Gleason score, PSA, and age were lower among LDR patients compared with HDR/SBRT. Unadjusted baseline IPSS score was similar among all groups. Adjusted IPSS worsened at all time points compared with baseline after LDR/HDR. At early/late time points, rates of IPSS MID after LDR were higher compared to HDR/SBRT. There were no IPSS differences between SBRT and HDR. All modalities showed early and late SHIM worsening. There were no temporal differences in SHIM between SBRT and brachytherapy. There were no differences in EPIC subdomains between HDR and SBRT. Bowel symptoms worsened early after SBRT, whereas urinary irritative/obstructive symptoms worsened late after HDR. Among all domains, MID after SBRT and HDR were similar. CONCLUSIONS: In a cohort of patients treated with modern radiotherapy techniques, HDR and SBRT resulted in clinically meaningful improved urinary PRQOL compared with LDR.