Sequential use of bacillus Calmette-Güerin (BCG) and mitomycin C (MMC) produced oncologic responses and low toxicity in well-selected patients who had high-risk nonmuscle-invasive bladder cancer (NMIBC), most of whom were previously unresponsive to BCG, according to a study published in Clinical Genitourinary Cancer.
This retrospective, single-center study included 22 patients who received sequential treatment. Fourteen of these patients had refused radical cystectomy (63.6%), 5 were unfit for surgery (22.7%), and 3 (13.6%) had other reasons for choosing a bladder-sparing treatment option.
Sequential treatment consisted of 6 instillations — BCG, BCG, MMC with electromotive drug administration (EMDA), BCG, BCG, and MMC with EMDA. The EMDA system uses an electrical current to ionize MMC, increasing its absorption and tissue concentrations. Induction was followed by 1 year of maintenance therapy.
Overall, the complete response rate with sequential treatment was 95.5% at 3 months and 6 months, 81% at 12 months, and 70% at 2 years. Among the 18 patients with disease that was previously unresponsive to BCG, the complete response rate was 100% at 3 months and 6 months, 82.4% at 12 months, and 68.8% at 24 months.
The investigators pointed out that patients had favorable pretreatment tumor characteristics. Half of treated tumors were single, 90% were smaller than 1.5 cm, 40% were GII, and 40% were Ta.
“BCG and MMC instillations administered with EMDA can be a good option for bladder preservation in well-selected patients with NMIBC who have failed a prior BCG treatment, avoiding the complications of a major surgery like radical cystectomy,” the investigators wrote.
At a median follow-up of 28.8 months, 10 patients had recurrences, and 6 had a high-grade recurrence. One patient progressed, underwent surgery, and eventually died due to metastatic disease.
The sequential treatment was considered well tolerated. Adverse effects occurred in 22% of patients. The most common toxicity was dysuria.
Sanz Gómez I, Huguet J, Bravo A, et al. Sequential treatment with bacillus Calmette-Güerin (BCG) and mitomycin C administered with electromotive drug administration (EMDA) in patients with high-risk non-muscle invasive bladder cancer after BCG failure. Clin Genitourinary Canc. doi:10.1016/j.clgc.2023.03.002
This article originally appeared on Renal and Urology News