Real-world Efficacy of Intravesical Gemcitabine for BCG-Unresponsive Non-Muscle-Invasive Bladder Cancer.

Purpose: This study aimed to report the real-world outcomes of intravesical gemcitabine for bacillus Calmette-Guérin (BCG) -unresponsive, high-risk, non-muscle-invasive bladder cancer (HR-NMIBC) in Korean patients who were unable or unwilling to undergo radical cystectomy (RC).

Materials And Methods: This retrospective study included 131 patients (median age: 69 years; 89% men) treated with intravesical gemcitabine for BCG-unresponsive HR-NMIBC at nine centers between May 2019 and April 2022. The primary endpoint was 1-year recurrence-free survival (RFS). The secondary endpoints included factors influencing RFS, progression-free survival (PFS), cystectomy-free survival, cancer-specific survival (CSS), overall survival (OS), and safety. Survival analysis was performed using the Kaplan-Meier method, and risk factors for recurrence were assessed using Cox regression models.

Results: Patients were followed up for a median duration of 25 months, with carcinoma in situ (CIS) in 42% of the patients. The 1-year and 2-year RFS rates were 68% and 42%, while the 1-year and 2-year PFS rates were 87% and 77%, respectively. No significant factors influencing RFS were identified. Seventeen patients underwent RC during a median follow-up of 16 months, with the condition in three patients progressing to muscle-invasive disease on final pathological analysis. The 2-year CSS and OS rates were 98% and 97%, respectively. Intravesical gemcitabine was well-tolerated, with only 7 patients (5.3%) unable to complete the full induction course.

Conclusion: Our research highlights the potential of intravesical gemcitabine as a viable bladder-sparing treatment option for BCG-unresponsive HR-NMIBC, providing real-world evidence on its safety, efficacy, and tolerability.