Between February 1990 and December 1991 high-dose epirubicin (Epi)(120 mg/m2) plus cyclophosphamide (CTX)(600 mg/m2) were given every 3 weeks to 52 patients with locally advanced and metastatic breast cancer. 26 patients with locally advanced disease received four courses of this regimen before and after local treatments. 26 patients had metastatic disease: they received eight courses unless progression or unacceptable toxicity occurred. Responses were seen in 37/48 (77%) evaluable patients including 14 complete responses (CR), 23 partial responses (PR), nine stable disease, two progressive disease. Among the 25 evaluable patients with locally advanced disease, 9 had a CR and 11 a > 80% decrease in tumour volume. 6 patients (24%) had a pathologically confirmed complete response. 18 patients (72%) had a tumour reduction to 0-2 cm. The 3-year disease-free survival was 60%. Of the 23 evaluable patients with metastatic disease, 5 obtained a CR and 10 a PR, yielding an overall response rate of 65%. Myelosuppression was substantial with a grade 3-4 leucopenia in 76% of the patients even if neutropenic fever occurred in only 7% of the courses. A clinical congestive heart failure occurred in 1 patient following a total Epi dose of 960 mg/m2 and a bilateral quadrantectomy and radiotherapy. We conclude that (1) high-dose Epi + CTX is a very active regimen, in particular for the patients with locally advanced breast cancer; (2) breast conservation after this regimen in some of these patients may be considered; (3) neutropenia is the dose-limiting toxicity. Currently, a phase II study using the same combination given every 2 weeks together with r-methuG-CSF is ongoing.