Responses to chemotherapy or chemohormonal therapy in advanced breast cancer patients treated previously with adjuvant chemotherapy. A subset analysis of CALGB Study 8081.

The Cancer and Leukemia Group B (CALGB) evaluated the response to subsequent chemotherapy or chemohormonal therapy in 46 patients with advanced breast cancer treated previously with adjuvant chemotherapy that had been completed 6 months or more before protocol entry. The results were compared with 379 patients in the same study who had not received prior adjuvant chemotherapy. The patients were treated with cyclophosphamide, Adriamycin (Adria Laboratories, Columbus, OH), and 5-fluorouracil (CAF), with or without tamoxifen. There was no difference in response rate, response duration, time to treatment failure, or survival between patients who had received prior adjuvant chemotherapy and those who had not. The addition of tamoxifen to CAF failed to enhance response rates or response durations in all subgroups. Women who relapsed 6 months or more after completion of adjuvant chemotherapy did not have inherently drug-resistant tumors. They responded to standard CAF chemotherapy with the same response rate and survival as patients untreated previously with chemotherapy.