A European Organization for Research and Treatment of Cancer--Genitourinary Group phase 2 study of chemotherapy in stage T3-4N0-XM0 transitional cell cancer of the bladder: evaluation of clinical response.

From 1986 to 1990 the European Organization for Research and Treatment of Cancer--Genitourinary Group conducted a phase 2 trial of neoadjuvant chemotherapy in patients with stage T3-4N0-XM0 transitional cell carcinoma of the bladder. The objectives were to evaluate the clinical response in relation to the pathological response, and to measure the side effects of chemotherapy. Of 171 patients entered 136 were fully evaluable: 18% had clinical complete remissions, 36% had clinical partial remissions, 39% had no clinical remissions and 10% had unknown response. A selected subgroup of 76 patients underwent cystectomy after 2 or 4 courses of chemotherapy: 2 were not evaluable for pathological response because of preoperative radiotherapy after neoadjuvant chemotherapy, 16 had a pathological complete remission, 7 had a pathological partial remission and 51 had no pathological remission. Comparison of the clinical response or T category only after 2 courses of chemotherapy with the pathological response after 2 or 4 courses of chemotherapy showed that in a number of patients the disease status could be downstaged to pathological complete or partial remission by additional courses of chemotherapy. If the discrepancies between clinical and pathological responses, or between T and P categories, induced by further downstaging after additional chemotherapy were left out, it was shown that clinical complete and partial remissions were a heterogeneous group but nonresponders could be delineated with a 100% accuracy by clinical response evaluation and transurethral resection biopsy only. Furthermore it seems important to establish the number of chemotherapy courses to induce a maximal response of the primary tumor.