Continuous intravenous infusion of 5-fluorouracil in the treatment of refractory breast cancer

Ten patients with metastatic breast cancer refractory to multiple chemotherapeutic regimens as well as hormonal therapy were treated with continuous intravenous infusion of 5-fluorouracil (5-FU) at 200-300 mg/m²/24 h through a Broviac catheter using a Cormed pump. The treatment was continued until toxicity developed and restarted after resolution of the toxicity. Most common dose-limiting toxicities were mucositis and diarrhea. No grade II or worse myelosuppression was documented. All the patients had received 5-FU by bolus injection before entering the study. We observed three partial responses and one improvement, with two patients continued on the study (396+ and 90+ days, respectively). We conclude that continuous infusion of 5-FU is safe and tolerable even by heavily pretreated patients with poor performance status and is not cross-resistant to bolus injection of 5-FU and other chemotherapeutic agents. Our report warrants further investigation.