Nine trials (2,820 patients) were included in the analyses of recurrence.
There was no overall difference in the risk of time to first recurrence between BCG and mitomycin C. Exploratory subgroup analysis illustrated a 32% (95% CI 25% to 39%) reduction in risk with BCG compared to mitomycin C. No maintenance resulted in a 28% (95% CI 18% to 38%) increase in risk with BCG compared to mitomycin C (test for interaction, Χ2=28.1, p<0.0001). BCG with maintenance was more effective than mitomycin C irrespective of previous chemotherapy regimen (prior chemotherapy p=0.026 and no prior chemotherapy p=0.0003).
Seven trials (1,880 patients) included data on time to progression to muscle-invasive disease, duration of overall survival and cancer-specific survival.
Twelve per cent of patients progressed to muscle-invasive disease (median follow up 4.8 years) with 24% mortality. Death was due to bladder cancer in 30% of patients. No statistically significant results between treatments were found for these long-term end points.