Long-term adverse effects after curative radiotherapy and radical prostatectomy: population-based nationwide register study

Objective: The aim of this study was to assess the risk of serious adverse effects after radiotherapy (RT) with curative intention and radical prostatectomy (RP). Materials and methods: Men who were diagnosed with prostate cancer between 1997 and 2012 and underwent curative treatment were selected from the Prostate Cancer data Base Sweden. For each included man, five prostate cancer-free controls, matched for birth year and county of residency, were randomly selected. In total, 12,534 men underwent RT, 24,886 underwent RP and 186,624 were controls. Adverse effects were defined according to surgical and diagnostic codes in the National Patient Registry. The relative risk (RR) of adverse effects up to 12 years after treatment was compared to controls and the risk was subsequently compared between RT and RP in multivariable analyses. Results: Men with intermediate- and localized high-risk cancer who underwent curative treatment had an increased risk of adverse effects during the full study period compared to controls: the RR of undergoing a procedures after RT was 2.64 [95% confidence interval (CI) 2.56–2.73] and after RP 2.05 (95% CI 2.00–2.10). The risk remained elevated 10–12 years after treatment. For all risk categories of prostate cancer, the risk of surgical procedures for urinary incontinence was higher after RP (RR 23.64, 95% CI 11.71–47.74), whereas risk of other procedures on the lower urinary tract and gastrointestinal tract or abdominal wall was higher after RT (RR 1.67, 95% CI 1.44–1.94, and RR 1.86, 95% CI 1.70–2.02, respectively). Conclusion: The risk of serious adverse effects after curative treatment for prostate cancer remained significantly elevated up to 12 years after treatment.