The prognostic value of the pathological response to combination chemotherapy of deeply invasive transitional cell cancer of the bladder was retrospectively assessed in 147 patients. Data were collected from 8 different centers. Patients were eligible if they had received intravenous combination chemotherapy followed by partial, total or radical cystectomy, and if they had a minimum followup of 2 years after the start of chemotherapy. Of the patients 90% received methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) or cisplatin plus methotrexate for a median of 3 courses (range 1 to 6). Of the 83 patients who were alive at analysis actuarial median followup was 30.5 months (range 13.2 to 85.6 months). A major pathological response (stage PO, Pis, Pa or P1) was achieved in 41.5% of the patients. Patients with a major pathological response (p stage less than 2) had a 5-year survival of 75% in contrast to 20% for the remaining nonresponding patients (p stage 2 or more). The survival of patients with a major pathological response was independent of whether the response was induced by 2 or more courses of chemotherapy, or whether it was induced by M- VAC in comparison with cisplatin plus methotrexate. Preoperative clinical assessments can identify nonresponding patients correctly and in these cases alternative treatment programs are required, since 80% will die of the disease. Moreover, if neoadjuvant chemotherapy is proved to increase survival, the data emphasize the importance of the response rate of the primary tumor and the need to investigate the optimal number of courses to induce the best response, preferably in the individual patient.