Longterm effects of hepatic arterial interleukin-2–based immunochemotherapy after potentially curative resection of colorectal liver metastases

Abstract

Background: Our previous study of hepatic arterial infusion of interleukin-2 (IL-2)–based immunochemotherapy demonstrated a high response rate of patients with unresectable liver metastases. In this study, we applied this therapy to the prevention of liver recurrence in patients who underwent potentially curative resection of liver metastases. Study Design: A pilot study was conducted of 18 patients with liver metastases from primary colorectal cancer who underwent potentially curative liver resection followed by adjuvant immunochemotherapy. The regimen consisted of a weekly hepatic arterial infusion of IL-2 (1.4–2.1 × 10 6 U) and 5-fluorouracil (250 mg) and a bolus of mitomycin C (2–4 mg) for 6 months. Results: Among 18 patients, 14 are still alive with a median postoperative survival of 52 months (as of April 1998). The 5-year overall survival rate was 75%. Although recurrent cancer developed in 6 of the 18 patients, no patients had recurrence in the residual liver. This complete prevention of liver recurrence is believed to have contributed to the high 5-year survival rate (75%) as compared with the survival rate of patients treated with surgery alone (average, 30%–40%) or with several other forms of adjuvant therapy. Conclusions: Interleukin-2–based immunochemotherapy is useful in combination with liver resection for the prevention of liver recurrence in colorectal cancer patients with liver metastases. A multicenter randomized trial is recommended.