Adjuvant chemotherapy with 5-fluorouracil after surgical resection of colorectal carcinoma (COG protocol 7041). A preliminary report.

In a prospectively randomized study the effect of adjuvant chemotherapy with 5-FU on survival and recurrence was analyzed in 274 evaluable patients with colorectal carcinoma who either underwent a curative or a palliative resection. In the treatment group, chemotherapy consisted of the intravenous administration of 5-FU 12 mg/kg daily for four consecutive days, then 6 mg/kg/per day on alternate days to the point of toxicity or to a maximum of 5 doses, followed by 12 mg/kg/week for one year. Drug toxicity was rarely severe and consisted of nausea and vomiting, diarrhea, stomatitis, leukopenia, and thrombocytopenia in slightly more than half of all patients. There have been no drug-related deaths. Analysis of the survival curves and disease-free interval curves reveal some evidence of drug benefit in both the curative group of resections and the palliative group of resections. However, this benefit is not significant except in those treated to toxicity. The disease-free interval after curative resection is significantly longer in patients treated with 5-FU to the point of toxicity with a white blood count less than 4,000 cells/mm3. We conclude that a preliminary analysis of the Central Oncology Group data in this trial does not make a convincing case for the use of 5-FU as an adjuvant to the surgical treatment of colorectal carcinoma.