This multicentre, randomised phase III study compared docetaxel with 5-fluorouracil+vinorelbine in patients with metastatic breast cancer after failure of neo/adjuvant or one line of palliative anthracycline-based chemotherapy. One hundred and seventy-six metastatic breast cancer patients were randomised to receive docetaxel (100 mg m ) D1 and D5 of each 3-week cycle. Eighty-six patients received 516 cycles of docetaxel; 90 patients received 476 cycles of 5-fluorouracil+vinorelbine. Median time to progression (6.5 vs 5.1 months) and overall survival (16.0 vs 15.0 months) did not differ significantly between the docetaxel and 5-fluorouracil+vinorelbine arms, respectively. Six (7%) complete responses and 31 (36%) partial responses occurred with docetaxel (overall response rate 43%, 95% confidence interval: 32 -53%), while 4 (4.4%) complete responses and 31 (34.4%) partial responses occurred with 5-fluorouracil+vinorelbine (overall response rate 38.8%, 95% confidence interval: 29 -49%). Main grade 3 -4 toxicities were (docetaxel vs 5-fluorouracil+vinorelbine): neutropenia 82% vs 67%; stomatitis 5% vs 40%; febrile neutropenia 13% vs 22%; and infection 2% vs 7%. There was one possible treatment-related death in the docetaxel arm and five with 5-fluorouracil+vinorelbine. In anthracycline-pretreated metastatic breast cancer patients, docetaxel showed comparable efficacy to 5-fluorouracil+vinorelbine, but was less toxic. Metastatic breast cancer (MBC) is sensitive to chemotherapy but remains incurable with current therapeutic approaches. Single agents such as doxorubicin or epirubicin, cyclophosphamide, 5-fluorouracil (5-FU) and methotrexate achieve overall response rates (ORRs) ranging from 20 to 50% in this setting (Henderson et al, 1987;Clavel and Catimel, 1993). Combinations of alkylating agents with anthracyclines are extensively used in MBC and yield ORRs ranging from 40 to 60%, with complete response rates 520%, and a median response duration 515 months (The French Epirubicin Study Group, 1991;Brufman et al, 1997;Del Mastro et al, 2001).Use of anthracyclines is associated with problems of cumulative cardiotoxicity and primary or secondary resistance. As a result, there is a limit to the cumulative dose and number of regimens that can be administered to any given patient. Subsequent therapy in case of treatment failure is, therefore, a problem. Single-agent docetaxel has been proposed as an alternative treatment for patients previously treated with anthracyclinebased therapy; the efficacy of this drug has been demonstrated in pretreated patients with MBC (Ravdin et al, 1995;Valero et al, 1995;Nabholtz and Crown, 1998;Alexopoulos et al, 1999;Brodowicz et al, 2000).In patients with anthracycline-resistant MBC, docetaxel (100 mg m 72 ), infused over 1 h every 3 weeks, induces ORRs ranging from 30 to 69% (Ravdin et al, 1995;Valero et al, 1995;Nabholtz and Crown, 1998;Alexopoulos et al, 1999;Brodowicz et al, 2000).Single-agent vinorelbine, in second-line or salvage chemotherapy for MBC, has a reported response rate of ...