Treatment of cancer with weekly intravenous 5-fluorouracil.Study by the Western Cooperative Cancer Chemotherapy Group (WCCCG)

Abstract

5-Fluorouracil (5-FU) has usually been administered by rapid intravenous injection of 15 mg/kg daily for 3-5 days and 7.5 mg/kg every 2 or 3 days to toxicity, repeated monthly (antitumor response about 10-30%). Drug morbidity and mortality have been excessive. Modifications of this course have shown similar response rates but decreased toxicity and mortality. In the present WCCCG study, 548 patients with disseminated cancer were treated weekly with 5-FU, without a loading dose, by rapid intravenous injection, beginning at 15 mg/kg/week for one month, and increased to 20 mg/kg/week (if necessary) to levels producing mild toxicity or an antitumor effect. Of the 339 patients now evaluated for response, 6 had complete responses, 54 had decreases in tumor size > 50%, and 34 had decreases in tumor size of 25-50%. The response rates > 50% (I-B and I-C) for adenocarcinoma of the breast, stomach, and colon were 37.8%, 28.6%, and 16%, respectively. Of the 430 patients evaluated for toxicity, 62 manifested no toxicity, and 368 patients had mild-to-severe toxicity. There were 8 drug-related deaths in patients who received 5-FU in dosages higher than those allowed in the protocol. There were no drug deaths in patients who received 5-FU as stipulated by the protocol.