High-dose intravesical epirubicin for BCG-unresponsive high-risk non-muscle-invasive bladder cancer

BACKGROUND: To report the oncological outcomes and tolerance of high-dose intravesical epirubicin in patients with BCG-unresponsive high-risk non-muscle invasive bladder cancer (NMIBC).METHODS: This was a retrospective single-arm monocentric study including all consecutive high-risk NMIBC treated with high-dose intravesical epirubicin at our institution between 2021 and 2024. The standard treatment regimen involves eight weekly intravesical instillations of 80 mg epirubicin (induction phase), followed by monthly instillations for one year (maintenance phase). Descriptive statistics were used to report baseline characteristics, oncological results and tolerance.RESULTS: Overall, nine patients with a median age of 72.7 (70.5-77.9) years were included in our study. After a median follow-up of 23.2 (17-23.8) months, three (33.3%) experienced disease recurrence after a median of 12.7 (9.3-15.7) months, including two (22.2%) cases of carcinoma in situ (CIS) and one (11.1%) case of high-grade pTa. Progression to MIBC occurred in one (11.1%) patient after 20.4 months. Among the four patients who had either high-grade recurrence (3/9) or progression (1/9), three underwent radical cystectomy after a median of 22.6 (20.9-22.9) months. Two (22.2%) patients died, but none of them from BC, after 9.8 and 21.1 months. Regarding tolerance, all nine patients experienced at least one side effect related to the epirubicin instillation. Pollakiuria (77.8%) and urinary burning (44.4%) were the most frequent side effects. Finally, one (11.1%) patient discontinued treatment due to side effect after 7 sessions of maintenance.CONCLUSIONS: Preliminary data suggest that high-dose epirubicin may be a safe and effective alternative treatment for high-risk NMIBC.