Aggressive adriamycin-containing regimen (PM-FAC) in estrogen receptor-negative disseminated breast cancer. Results of a Southwest Oncology Group trial.

Sixty-four patients with disseminated breast cancer were treated with an aggressive chemotherapy program of prednisone, methotrexate, 5-fluorouracil, Adriamycin (doxorubicin) and cyclophosphamide (PM-FAC). A response rate of 76% was seen in 44 estrogen receptor (ER) negative patients, with 26% achieving complete responses. Forty-two percent of 20 ER positive and unknown patients demonstrated a response, but in none was a complete response achieved. Median response duration was 9 months for complete responders and 5 months for partial responders. The median survival for both groups of patients was 13 months. However, survival among the responding patients was inferior for the ER negative group (median, 14 versus 20 months; P = 0.05). These findings suggest selective sensitivity of ER negative breast cancer to Adriamycin-containing chemotherapy. Despite aggressive chemotherapy, no durable remissions were achieved. Relapse occurred at sites of known prior involvement, and in the central nervous system de novo, especially in the ER negative patients.