Long‐term patient‐reported outcomes and toxicity following salvage radiotherapy for biochemical recurrence after radical prostatectomy

BACKGROUND: Salvage radiotherapy (RT) after prostatectomy is common, but studies reporting long-term follow-up on patient-reported outcomes (PROs) and toxicity are limited. The authors report the largest cohort of patients treated with intensity modulated radiotherapy (IMRT) to date assessing patient-reported quality of life (QOL) and physician-rated toxicity with long-term follow-up. METHODS: PROs were prospectively collected for men undergoing post-prostatectomy salvage IMRT. Declines in quality of life were defined using established minimum clinically important difference (MCID) thresholds for bowel function (BF), sexual function (SF), urinary incontinence (UI), and urinary obstruction/irritation (UO) domains. Physician-reported genitourinary (GU) and gastrointestinal (GI) toxicities were recorded with Common Terminology Criteria for Adverse Events v3.0. RESULTS: Between 2007 and 2019, 317 men were treated to a median dose of 68.4 Gy to the prostate bed with 72% receiving pelvic nodal treatment and 72% receiving androgen deprivation therapy. Median follow-up was 63 months. The median scores for UI, UO, BF, and SF did not decline more than the MCID at any time point except for the 6-week bowel score. At 5 years, the percentage of men with QOL decline exceeding MCID for BF, SF, UI, and UO domains were 23%, 25%, 29%, and 31%, respectively. The cumulative incidences of grade 3+ GU and GI toxicity at 5 years were 5.1% and 1.6%, respectively. CONCLUSION: Median patient-reported QOL scores remained largely stable following salvage RT after radical prostatectomy, although clinically meaningful declines occurred in a subset of patients. QOL decline and physician-rated toxicity were transient in approximately one-third of affected patients.