A comparison of doxorubicin, epirubicin and mitozantrone as single agents in advanced breast carcinoma

Between July 1985 and December 1987, 87 patients with advanced breast carcinoma were randomized to receive single agent doxorubicin (70 mg/m2), epirubicin (70 mg/m2) or mitozantrone (14 mg/m2) at 3-weekly intervals. The patients had received no previous chemotherapy for their advanced disease but 91% had received prior hormonal therapy. The response rates were 36% with doxorubicin, 32% with epirubicin and 26% with mitozantrone, but these differences did not reach statistical significance. The median survival of all patients was 8.3 months. There was no significant difference in response rates or survival according to menopausal status. The toxicities of the three agents are compared. Nausea, vomiting and alopecia were more severe in patients treated with doxorubicin or epirubicin than those treated with mitozantrone. Myelosuppression and infective episodes occurred more frequently with mitozantrone. Two cardiac complications were reported. This study shows that the toxicity and low efficacy of all three agents limit their use as single agents in advanced breast carcinoma. The role of single agent chemotherapy and the relative toxicities of these drugs are discussed.