Abstract Purpose The aim of this study was to evaluate late genitourinary (GU) toxicities on receiving intensity-modulated radiation therapy (IMRT) in patients with prostate cancer (PCa) who had a history of invasive interventions for the prostate or bladder. Materials and methods Among patients who received IMRT for PCa at our institution between August 2000 and December 2022, clinical outcomes among those with a history of invasive interventions for the prostate or bladder were retrospectively analyzed. Cumulative incidence rates of late ≥ grade 2 and ≥ grade 3 GU and gastrointestinal toxicities, and rates of overall survival (OS) and biochemical failure-free survival (BFFS) were evaluated. Results A total of 32 consecutive patients were analyzed, among whom 28 received conventional fractionated IMRT with a median dose of 74 Gy in 37 fractions, and 4 underwent moderately hypo-fractionated IMRT with a median dose of 54 Gy in 15 fractions. The median follow-up period was 77.3 months after IMRT. Cumulative incidence rates of ≥ grade 2 and ≥ grade 3 GU toxicities were 20.7 and 4.3% at 5 years, and 26.4 and 4.3% at 8 years, respectively. More than 10 years after IMRT, 18.8% of patients developed ≥ grade 2 GU toxicities. OS and BFFS rates were 89.5 and 76.0% at 5 years, and 89.5 and 60.7% at 8 years, respectively. Conclusion Prostate IMRT for patients with a history of invasive interventions for the prostate or bladder was considered a safe and feasible treatment option, although the incidence of late GU toxicities was relatively high. Long-term follow-up with close attention to the detection of GU toxicities is recommended for such a population. Secondary abstract Clinical outcomes of IMRT in 32 patients with prostate cancer and a history of invasive interventions for the prostate or bladder were retrospectively analyzed. Although the incidence of late genitourinary toxicities was relatively high, prostate IMRT was considered a safe and feasible treatment option for such a population.
Kato et al. (Sat,) studied this question.