Adjuvant intravesical treatment in patients with intermediate and high-risk non-muscle-invasive bladder cancer with BCG versus MMC applied with COMBAT or EMDA. Results of a prospective study

Abstract

Background: Bacillus Calmette–Guerin (BCG) maintenance therapy is the standard adjuvant treatment of high- and intermediate-risk non-muscle-invasive bladder cancer (NMIBC). However, the problems of shortages and the adverse effects, both local and systemic, that it causes lead to the search for alternatives with devices that improve the penetration of intravesical chemotherapeutics. Materials and methods: Prospective observational study was conducted from August 2018 to August 2022. Patients diagnosed with intermediate and high-risk NMIBC without CIS who received one of the following three treatments were included: BCG in induction protocol with six weekly instillations and maintenance with three weekly instillations at months 3, 6, and 12. MMC was applied by Physionizer® 30 device with a current of 20 mA for 30 min was used in an induction protocol of 6 weekly instillations followed by 6 monthly instillations as maintenance (EMDA group). MMC was applied by COMBAT BRS System V2.0 device at 43 ± 0.5 ℃ for 60 min was used in an induction protocol of 6 weekly instillations followed by 6 monthly instillations as maintenance (HIVEC group). The primary objective was to compare the 24-month recurrence-free rate between the three groups. The secondary objectives were to evaluate the rate free of progression at 24 months and the degree of toxicity of the treatments. Results: One hundred and eighty-three patients divided into a HIVEC group with sixty-one patients, EMDA group with fifty-nine patients, and BCG group with sixty-three patients. After a mean follow-up of 25 months (IQR 13–36), the 24-month recurrence-free rate was 82.1% for HIVEC, 80% for EMDA, and 84.6% for BCG (p > 0.05), and a progression-free rate at 24 months of 95.6% for HIVEC, 98.3% for EMDA, and 92.9% for BCG (p > 0.05). No statistically significant differences were found between the three groups with respect to the degree of reported adverse events. Conclusion: Adjuvant treatment with BCG or MMC applied with COMBAT or EMDA does not present differences in the recurrence-free rate and progression at 24 months in our population of patients with intermediate- and high-risk NMBC without CIS.