De Angelis et al. investigated these differences in 347 patients with RT-BC (3%) and 9610 patients with primary BC (97%) from the Surveillance, Epidemiology, and End Results (SEER) database. The 5-year cancer-specific mortality (CSM) rate was significantly higher in patients with RT-BC (42.7%) than in patients with primary BC (38.1%; p < 0.001). A multivariate competing risks regression (CRR) model revealed that RT-BC was not an independent predictor of higher CSM relative to primary BC (p = 0.09). The 5-year other-cause mortality (OCM) rate was significantly higher in RT-BC patients (20.5%) compared to primary BC patients (11.4%; p < 0.001). Multivariable CRR models revealed that RT-BC was an independent predictor of higher OCM (HR, 1.3; 95% CI, 1.1 – 1.6; p = 0.01). To determine whether there were differences specific to the type of radiation exposure, the investigators subsequently conducted a sensitivity analysis in patients with non-organ-confined (NOC) disease. The multivariable CRR model revealed that EBRT was an independent predictor of higher OCM in patients with NOC disease (HR, 1.5; 95% CI, 1.1 – 2.2; p = 0.01).
Overall, while RC appears to be effective in patients with RT-BC, there was higher OCM in this group. The retrospective population-based study and the lack of availability of other clinical variables, including comorbidities and treatment details, limit the interpretation of these data.
Written by: Bishoy M. Faltas, MD, Director of Bladder Cancer Research, Englander Institute for Precision Medicine, Weill Cornell Medicine
References:
- de Angelis M, Siech C, Di Bello F, et al. Mortality rates in radical cystectomy patients with bladder cancer after radiation therapy for prostate cancer. BJU Int. Published online October 27, 2024. doi:10.1111/bju.16571