Continuous infusion fluorouracil in the management of advanced breast cancer: A phase II study

Aims and background: The evaluation of unconventional schedules of well- known drugs represents a promising avenue in the search for new regimens with a better therapeutic index in metastatic breast cancer. In particular, protracted continuous infusion (PCI) of 5-fluorouracil (5-FU) has yielded interesting results in gastrointestinal malignancies and in breast cancer. Methods: From March 1996 30 consecutive patients with heavily pretreated breast cancer were treated with PCI 5-FU at a daily dose of 250 mg/m² by means of disposable elastomeric pumps until progression or toxicity. The median age was 54 years (range, 28-71) and median performance status was 1 (range, 0-3). All patients but four were pretreated with anthracycline- containing regimens or taxanes; the median number of chemotherapy lines was 3 (range, 2-4). Metastatic sites were predominantly visceral in 60% of the patient population. Results: All 30 patients were evaluable for response and toxicity. The median duration of PCI was 20 weeks (range, 2-36 weeks). Two complete responses (7%) and eight partial remissions (26%) were observed, giving an overall response rate of 33%. The median duration of response was six months (range, 4-9 months). Stabilization was observed in seven patients (23%) with a median duration of seven months (range, 3-9 months). The main toxic effects were grade I-II mucositis and hematologic toxicity, while grade 3 hand-foot syndrome was observed in eight patients (27%). Conclusions: This study confirms the efficacy and safety of 5-FU at this dosage and schedule in heavily pretreated women with advanced breast cancer. In order to improve on these results further studies are needed in a less advanced stage of the disease and together with other active drugs.