Concentration of biologically active 5-fluorouracil in general circulation during continuous portal infusion in man: a preliminary report.

5-Fluorouracil (5-FU) was administered to 8 patients with malignant liver tumours either by regional portal or general intravenous infusion. During continuous portal infusion of 15 mg 5-FU/kg/24 h, systemic serum-concentrations were generally below 100 ng/ml and no side-effects were seen. Intravenous infusion of the same dose was accompanied by serum-concentrations above 100 ng/ml and bone-marrow depression. This preliminary study indicates that there are better prerequisites for high anti-toumour effect and low frequency of side-effects during portal infusion of 5-FU than during general intravenous administration to patients with liver tumours.