Quinolone Prophylaxis in Conjunction with Bacillus Calmette-Guérin Instillations for Bladder Cancer: Time To Reconsider the Evidence and Open the Quinolone Box?

Adjuvant bacillus Calmette-Guérin (BCG) instillations represent a cornerstone in the treatment of non-muscle-invasive bladder cancer. Instillation schedule and dose modifications have been evaluated in efforts to reduce the incidence of adverse events (AEs), but none so far has the same treatment efficacy as the full-dose recommended schedule. It has been shown that prophylactic quinolone use in conjunction with BCG instillations reduces AE incidence and improves timely completion of instillation regimens and patient survival. However, the European Medicines Agency imposed restrictions on the use of quinolones in 2019 because of side effects. Nevertheless, rational use of quinolone prophylaxis could be considered for selected individuals treated with BCG without risk factors for quinolone-associated side effects in conjunction with patient information about side-effect symptoms. PATIENT SUMMARY: Bladder instillations of BCG (bacillus Calmette-Guérin) are used in the treatment of non-muscle-invasive bladder cancer. Antibiotics from the quinolone class can reduce the adverse effects of BCG and help patients in completing the treatment course; however, these antibiotics have their own side effects. Our mini review suggests that the antibiotics could be used in selective cases if patients are given adequate information on these side effects and their symptoms.