Evaluation of high-dose versus standard FAC chemotherapy for advanced breast cancer in protected environment units: a prospective randomized study.

Abstract

Fifty-nine evaluable patients under 65 years of age with measurable metastatic breast cancer and without prior chemotherapy were randomly assigned to treatment with fluorouracil, Adriamycin (Adria Laboratories, Columbus, OH), and cyclophosphamide (FAC) at standard or high doses (100% to 260% higher than standard FAC) following a dose escalation schedule. Patients randomized to the high-dose FAC received the first three cycles of therapy within a protected environment. Subsequent cycles for this group were administered at standard doses of FAC in an ambulatory setting, the same as for the control group. After reaching 450 mg/m2 of Adriamycin, patients in both groups continued treatment with cyclophosphamide, methotrexate, and fluorouracil until there was disease progression. Analysis of pretreatment patient characteristics showed an even distribution for most known pretreatment factors, although the control group had slightly (but nonsignificantly) more favorable prognostic characteristics. Fourteen patients (24%) achieved a complete remission (CR) and 32 (54%) achieved a partial remission (PR), for an overall major response rate of 78%. There were no differences in overall, CR, or PR rates between the high-dose FAC and control groups. The median response durations were 11 and 10 months for the protected environment and control groups, respectively, and the median survival was 20 months for both groups. Hematologic, gastrointestinal (GI), and infection-related complications were significantly more frequent and severe in the group treated with high-dose chemotherapy. Stomatitis, diarrhea, and skin toxicity were dose-limiting. However, there were no treatment-related deaths. High-dose induction combination chemotherapy with the agents used in this study failed to increase the response rate or survival duration, and resulted in a substantial increase in toxicity.