A randomized comparison of single-agent doxorubicin and epirubicin as first-line cytotoxic therapy in advanced breast cancer.

One hundred forty-one patients with advanced breast cancer who had not received prior chemotherapy were randomly assigned to receive doxorubicin 60 mg/m2 or epirubicin 90 mg/m2 every 3 weeks. These doses were selected to produce equivalent toxicities. All patients were assessed for toxicity, and 138 patients were assessable for response. After a median of five treatment cycles, 47% (32 of 68) of doxorubicin-treated patients achieved a partial or complete response. Response duration and survival were 10 and 12 months for doxorubicin and 8 and 10 months for epirubicin, respectively. Noncardiac toxicities were similar for both drugs. Of 41 patients receiving doxorubicin who had serial left ventricular ejection fraction assessments, seven sustained a fall of 10% or more, and one patient developed congestive cardiac failure at a cumulative doxorubicin dose of 489 mg/m2. Of 39 patients receiving epirubicin who had serial cardiac assessments, five sustained left ventricular ejection fraction falls of 10% or more and two patients developed congestive cardiac failure at cumulative doses of 178 mg/m2 and 833 mg/m2. These data indicate that an epirubicin dose of 90 mg/m2 produces toxicity equivalent to doxorubicin 60 mg/m2 but does not improve response rates, response duration, or survival in advanced breast cancer.