A colon adenocarcinoma cell suspension is inoculated intrahepatically in a rodent experimental model. Intravenous 5-FU (30 mg/kg) in combination with Folitixorin (15 mg/kg or 30 mg/kg) is administered after 1, 2, 3, 4 and 7 days. 5-FU in combination with Folitixorin (regardless of folate-dose) eliminats tumor take.