5-Fluorouracil continuous infusion in metastatic colorectal cancer

5-Fluorouracil (5-FU) remains the most active therapeutic agent in advanced colorectal cancer. This drug has demonstrated differing levels of activity dependent on the schedule of administration in experimental and clinical models. Twenty-six patients were treated with prolonged continuous infusion of 5-FU at 250 mg/m2/day via a portable infusion pump and Hickman's central venous catheter in this study. Twelve patients (46%) experienced a major response (complete response-1, partial response-11). Median duration of response was 5 months. Seventeen patients were chemotherapy-naive on accrual to this study. Ten patients from this group had partial responses (59%) and four were minor responders (24%). Hence 82% of patients who had no prior chemotherapy showed tumour responses to 5-FU continuous infusion. Two of nine patients (22%) with prior chemotherapy achieved major response. Favourable toxicity profile was noted with this regimen. Two patients discontinued therapy due to treatment-related toxicities (severe palmar-plantar erythrodysesthesia and superior vena cava thrombosis secondary to the central venous catheter). Prolonged continuous infusion of 5-FU could well be the standard treatment of advanced colorectal cancer in view of its favourable activity and toxicity profile. The serial serum carcino-embryonic antigen (CEA) trend was shown to correlate well to the objective response; a decline of more than 50% from baseline CEA level correlated with a major response and a rise of more than 50% correlated with progressive disease. Hence the use of serum CEA is suitable for monitoring response to chemotherapy which is advantageous with respect to patient convenience and cost-effectiveness.