We administered interleukin (IL)-2 with mitomycin C (MMC) and 5-fluorouracil (5-FU) by hepatic arterial infusion for the treatment of liver recurrence from colorectal cancer. The regimen consisted of continuous hepatic arterial infusion of IL-2 (7 x 10(5) JRU/day)/5-FU (250 mg/day) for 4 weeks. After those 4 weeks, a weekly hepatic arterial infusion of IL-2 (2.1 x 10(6) JRU)/5-FU (250 mg) was performed more than 4 weeks. MMC (4 mg) was given as a bolus weekly. This therapy resulted in partial response (PR) in one case, progressive disease (PD) in one case, and no change (NC) in one case. The toxicity of the therapy was a slight in all cases. We herein report 3 patients treated with hepatic arterial infusion of IL-2 with MMC and 5-FU for liver recurrence from colorectal cancer. This therapy may be a new strategy for metastatic colorectal cancer.