Clinical Efficacy of Neoadjuvant Intravesical Mitomycin-C Therapy Immediately Before Transurethral Resection of Bladder Tumor in Patients With Nonmuscle-invasive Bladder Cancer: Preliminary Results of a Prospective, Randomized Phase II Study.

Abstract

Intravesical mitomycin-C is recommended immediately after transurethral resection of bladder tumor for nonmuscle-invasive bladder cancer. However, a lack of compliance occurs due to the associated complications. Here, we aimed to assess the efficacy and safety of intravesical mitomycin-C before transurethral resection of bladder tumor in patients with nonmuscle-invasive bladder cancer. This was a single-center, open-label, parallel-arm, randomized phase II clinical trial in patients with suspected nonmuscle-invasive bladder cancer before transurethral resection of bladder tumor. Participants were randomly assigned (1:1) to receive 2 doses of intravesical mitomycin-C (40 mg/20 mL) 1 day and 4 hours before transurethral resection of bladder tumor (n = 49) or no treatment (n = 50) with block randomization (size 2 and 4), stratified by bacillus Calmette-Guérin/intravesical mitomycin-C. The primary endpoint was recurrence-free survival and secondary endpoints were progression-free survival and adverse events in the per-protocol analysis. Seventy-one patients (33, intervention; 38, control) were well matched for baseline characteristics. Sixty-one had been followed without recurrence for at least 10.4 months; 3 and 8 patients showed recurrence in the intervention and control groups, respectively. The 1-year recurrence-free survival rate was 97% and 89% for the intervention and control groups, respectively. Neoadjuvant intravesical mitomycin-C resulted in a reduction (63%) in the relative recurrence risk (hazard ratio, 0.37; 80% 1-sided confidence interval, -∞-0.65, P = .11). Disease progression occurred in 3 patients in the control group (P = .051) but not in the intervention group. Neoadjuvant intravesical mitomycin-C was well tolerated, and adverse events were local and of grade 1/2. Two doses of neoadjuvant intravesical mitomycin-C are safe and effective in reducing nonmuscle-invasive bladder cancer recurrence and progression after transurethral resection of bladder tumor.