Superficial bladder tumors treated at the Henri Mondor Hospital from 1984 through 1988 were analyzed for recurrence and progression using the following prognostic parameters: stage (TNM classification, 1978), grade (G1, G2, G3), size, number of tumors, and tumor malignancy index as defined by the Besançon group. Forty-five patients were treated with transurethral resection alone (TUR group) whereas 30 had TUR followed by the prophylactic instillation of fresh Calmette-Guérin bacillus in the bladder (BCG group). In TUR patients, parameters predictive of progression included grade G3, multiple tumors, stage T1, recurrence within 6 months of TUR, and a tumor malignancy index above 455. None of these criteria were predictive of a response to BCG. Results obtained in the BCG group were comparable to those reported in the literature and confirmed the efficacy of BCG instillations to prevent recurrence and progression of superficial carcinomas of the bladder.