[Mitomycin C for the treatment of superficial tumors of the bladder (Tis-Ta-T1) with one or more risk factors. Argentinian Cooperative Group of Oncourology (GCAO)]. / Mitomicina-C para el tratamiento de los tumores superficiales de vejiga (Tis-Ta-T1) con uno o más factores de riesgo. Grupo Cooperativo Argentino de Oncourología (GCAO).

OBJECTIVES: To determine the efficacy and toxicity of intravesical mitomycin C in superficial bladder tumors (Tis Ta T1) completely resected with one or more risk factors. (Protocol U. 01/90). METHODS: The patients received six instillations weekly of 40 mg mitomycin C within 15 days post-TUR of a superficial bladder tumor with one or more risk factors: histological grade 3, tumor size more than 3 cm and/or multicentric lesion. The patients were evaluated by cystoscopy every three months for the first two years and every six months thereafter. Toxicity was evaluated according to Miller's score. Tumor recurrence, disease-free interval and survival were analyzed. RESULTS: 126 patients were entered into the study; of these, 110 were evaluable. At 18 months mean follow-up (range 6-36 months), 77 patients (70%) remain disease-free; the mean time to recurrence was 13.8 months. There were no differences between patients with one, two or three risk factors or those who received or did not receive previous treatments. The patients tolerated the treatment well; there were no dropouts or systemic toxicity. CONCLUSIONS: 1. At 18 months mean follow-up, 77 of 110 patients (70%) remain disease-free; 2. The mean time to recurrence was 13.8 months; 3. Local toxicity was minimal; 4. There were no dropouts due to toxicity; 5. Systemic toxicity was not observed.