Abstract
Radical cystectomy and bladder preservation therapy are effective for muscle-invasive bladder cancer (MIBC); however, many patients over 70 are medically unfit for these options. For such patients, radiotherapy serves as a viable alternative. This study compares survival outcomes of radiotherapy versus supportive care in MIBC patients ineligible for cystectomy or bladder preservation with concurrent chemoradiotherapy. Using the Taiwan Cancer Registry and National Health Insurance Research Database (2011-2020), we identified patients with cT2-T4N0-1M0 urinary bladder urothelial carcinoma. Patients were excluded if they had undergone cystectomy or chemotherapy. Patients received either radiotherapy or supportive care, with endpoints of overall survival (OS) and cancer-specific survival (CSS) analyzed by Kaplan-Meier and multivariate Cox regression. Among 485 MIBC patients, 301 (62%) received radiotherapy, and 184 (38%) supportive care. After 13.93 months of median follow-up, radiotherapy significantly improved OS and CSS (P<0.001). Mortality rates were 26.9% for radiotherapy and 76.1% for supportive care at one year, and 59.5% vs. 94.0% at three years. OS and CSS benefits were confirmed for stages II-IV (adjusted hazard ratios: 5.47, 3.23, and 12.44, respectively), with T3, T4, N1, and chronic obstructive pulmonary disease (COPD) predicting worse OS. In conclusion, radiotherapy offers superior survival benefits compared to supportive care in MIBC patients who are unfit for cystectomy or chemoradiotherapy. These findings provide valuable insights for clinicians in making treatment decisions, particularly for elderly or medically unfit patients with early or locally advanced-stage MIBC.