Eur Urol. 2007;52:1398-1406
One third of the standard dose of bacillus Calmette-Guérin (BCG) could be recommended as adjuvant treatment for intermediate-risk superficial bladder tumors, Spanish researchers say.
In 430 patients with these tumors, the investigators compared three regimens: a low dose of BCG 27 mg (one third of the standard dose), BCG 13.5 mg, and mitomycin C (MMC) 30 mg. Instillations were repeated once a week for six weeks followed by six instillations once every two weeks over a period of 12 weeks.
Patients in the BCG 27 mg group had a significantly longer disease-free survival interval compared with patients in the MMC group. Compared with the BCG 27 mg group, the MMC and BCG 13.5 mg groups were at 86% and 49% higher risk of death after adjusting for potential confounders.
Disease-free survival was not significantly different between the two BCG groups or between the BCG 13.5 mg and MMC groups. The researchers observed no significant differences among the three groups with respect to time to progression and cancer-specific survival time. Local and systemic toxicities were higher in both BCG groups.
The BCG 27 mg dose seems to be the minimum effective dose as adjuvant treatment for intermediate-risk superficial bladder cancer, the authors concluded. BCG 13.5 mg is similar in efficacy to MMC 30 mg but is more toxic.