The long-term incidence and quality of life outcomes associated with treatment-related toxicities of external beam radiotherapy for prostate cancer.

To assess the long-term incidence of treatment-related toxicities and quality of life (QOL) outcomes associated with toxicity after external beam radiotherapy (EBRT) for prostate cancer.

We identified all men who had EBRT between 1994-2017 from CaPSURE, a longitudinal, nationwide prostate cancer registry. CaPSURE was queried for patient-reported and ICD-9/10 and CPT codes. The Medical Outcomes Studies Short Form 36 and the University of California, Los Angeles Prostate Cancer Index was used to provide measures of general health, sexual, urinary and bowel function. Repeated measures mixed models were used to determine QOL change after onset of toxicity.

From a total of 15,332, 1,744 (11.4%) men had EBRT. The median follow-up was 7.9 years (IQR 4.3-12.7). The median time to onset of any toxicity including urinary pad usage in 265 (15.4% at 8 years) men was 4.3 years (IQR 1.8-8.0). The most frequent toxicity was cystitis (104, 5.9% at 8 years) after a median of 3.7 years (1.3-7.8), gastrointestinal (48, 2.7% at 8 years) after a median of 4.2 years (IQR 1.3-7.8), followed by urethral stricture (47, 2.4% at 8 years) after a median of 3.7 years (IQR 1.9-9.1). Repeated measures mixed models found that onset of cystitis was associated with change in general health over time.

EBRT for prostate cancer is associated with distinct treatment-related toxicities which can occur many years after treatment and can affect quality of life. These results may help men understand the long-term implications of treatment decisions.

Urology. 2023 May 25 [Epub ahead of print]

Peter E Lonergan, Avi Baskin, Scott A Greenberg, Osama Mohamad, Samuel L Washington, Shoujun Zhao, Janet E Cowan, Jeanette M Broering, Hao G Nguyen, Matthew R Cooperberg, Benjamin N Breyer, Peter R Carroll

Department of Urology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco; Department of Urology, St. James's Hospital, Dublin, Ireland; Department of Surgery, School of Medicine, Trinity College Dublin, Ireland. Electronic address: ., Department of Urology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco., Department of Urology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco; Department of Radiation Oncology, University of California, San Francisco., Department of Urology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco; Department of Epidemiology & Biostatistics, University of California, San Francisco., Department of Urology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco; Department of Surgery, University of California, San Francisco.