Comparing efficacy and safety of in-house gemcitabine to mitomycin for bladder instillation in intermediate-risk NMIBC.

INTRODUCTION

Intermediate-risk (IR) Non-Muscle Invasive Bladder Cancer (NMIBC) is associated with a high rate of tumor recurrence. To improve patient outcomes, it is recommended to use adjuvant intravesical therapy, by mitomycin C (MMC) or Bacillus Calmette Guerin (BCG). Gemcitabine (GMC) is a known molecule used in urothelial cancer. We aimed to study the efficacy and safety profile of a gemcitabine solution, compared to mitomycin C, in the treatment of IR NMIBC.

MATERIAL: In this retrospective study, patients with IR NMIBC treated between 2016 and 2020 were selected from two participating centers using either gemcitabine (center A) as the intravesical chemotherapy regimen or mitomycin C (center B). The primary endpoint was recurrence rate and secondary end points were treatment interruption and its causes.

RESULTS

In our cohort of 102 IR NMIBC patients, 49 patients received GMC and 53 MMC with a median follow-up of 30 months. Overall recurrence rate was 42.1% with 22.4% in the GMC group and 60.3% in the MMC group (P<0.01). This difference was also found in the multifactorial analysis. Course interruption was observed in 14.7% of all patients, primarily attributed to adverse events (46.6%), without difference between groups.

CONCLUSION

Adjuvant intravesical gemcitabine in patients with IR NMIBC seems to be an interesting option associated with a lower tumor recurrence rate and a favorable tolerance profile when compared to MMC. Larger scale prospective randomized trials are needed to validate our findings.

LEVEL OF EVIDENCE: III.