Prophylactic effects of Bacille Calmette-Guérin intravesical instillation therapy: time period-related comparison between Japan and Western countries.

Guidelines change every few years regarding the prophylactic use of Bacille Calmette-Guérin (BCG) against non-muscle invasive bladder cancer. We performed a retrospective comparison to clarify the differences in BCG efficacy, based on time period, between Japan and Western countries . Published literature on 18 Japanese and 28 Western patient studies were compared to evaluate differences in BCG efficacy. Additionally, Internet searches were performed to obtain comparative Japanese and Western data. BCG efficacy in Japanese literature tended to show decreasing non-recurrence rates by time period. Non-recurrence rates in Western countries increased each year. This discrepancy may stem from a number of factors, including changes in accepted BCG indications, the introduction of restaging transurethral resection (re-TUR), the concept of BCG maintenance, and the evolution of histopathological diagnostic criteria.