Combination chemotherapy and high-dose cyclophosphamide intensification for poor prognosis breast cancer. A Southwest Oncology Group Study.

ABSTRACT

Thirty-seven patients with poor prognosis, metastatic breast cancer were treated with 5-fluorouracil, vinblastine, and Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH) (FUVA) induction chemotherapy. All 26 patients (74%) with responsive or stable disease after induction chemotherapy received intensification with high-dose cyclophosphamide (120 mg/kg). Continued responders received additional FUVA as consolidation. The response rate to induction therapy was 54% (with complete response [CR] in 11%). With intensification, three patients (11%) showed improved response (partial response [PR] in one, PR to complete response [CR] in two); however, six patients (23%) progressed within 2 months of cyclophosphamide intensification, three within 1 month. The overall response rate to all three phases of the study was 69%, with CR in 23%. The median survival of all patients entered in this study was 15 months. For cyclophosphamide intensification, major toxicity consisted of leukopenia with fever requiring broad-spectrum antibiotics in 27%. The authors conclude that a single cycle of high-dose cyclophosphamide intensification in metastatic breast cancer does not result in significantly improved responses or prolonged survival.