Sequential use of bacillus Calmette-Güerin (BCG) and mitomycin C provides oncologic response with low toxicity in well-selected patients who have high-risk nonmuscle-invasive bladder cancer (NMIBC) and initial BCG failure, a new study finds.
In a retrospective, single-center study of 22 patients who received sequential treatment, 14 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 option. Induction therapy consisted of 6 instillations in the sequence of BCG, BCG, and mitomycin C with electromotive drug administration (EDMA). The EMDA system uses an electrical current to ionize mitomycin C, increasing its absorption and tissue concentrations. Induction was followed by 1 year maintenance therapy.
Overall, the complete response rate with sequential treatment was 95.5% at 3 and 6 months, 81% at 12 months, and 70% at 2 years, Isabel Sanz Gómez, MD, of Fundació Puigvert, Universitat Autònoma de Barcelona in Spain, and colleagues reported in Clinical Genitourinary Cancer. Among 18 patients with BCG unresponsive disease, complete response was 100% at 3 and 6 months, 82.4% at 12 months, and 68.8% at 24 months.
The investigators pointed out that patients had favorable pre-treatment tumor characteristics. Half of treated tumors were single, 90% were smaller than 1.5cm, 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 to a prior BCG treatment, avoiding the complications of a major surgery like radical cystectomy,” the investigators wrote.
Over a median 28.8 months, 6 patients (27%) experienced high-grade recurrence. One patient progressed, underwent surgery, and eventually died due to metastatic disease.
With respect to safety, the sequential treatment was well tolerated. Adverse effects, mostly dysuria, occurred in 22%.
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