Complete remission of liver metastases from colorectal cancer by treatment with a hepatic artery infusion (HAI) of interleukin-2-based immunochemotherapy: reports of three cases

Abstract

In an attempt to improve the therapeutic efficacy against liver metastases, a hepatic arterial infusion (HAI) of interleukin-2 (IL-2)-based immunochemotherapy for anticipating the regional potentiation of hepatic lymphokine-activated killer (LAK)/tumor-infiltrating lymphocytes (TIL) was initiated. We present herein the cases of three patients with multiple liver metastases from colorectal cancer in whom complete remission was achieved by treatment with an HAI of IL-2 in combination with mitomycin C (MMC) and 5 fluorouracil (5-FU). These patients received an HAI of IL-2 at 8 x 10⁵ JRU, 5-FU at 250 mg daily, and MMC at 4 mg once weekly for 3 weeks, being the induction regimen, after which they were discharged on maintenance therapy consisting of IL-2 at 2 X 10⁶ JRU, 5-FU at 250 mg twice weekly, and MMC at 4 mg once weekly. It was evident from the liver CT scan taken after 2–3 months that the metastatic foci seen before therapy had clearly disappeared, while the serum carcinoembryonic antigen (CEA) had decreased to normal levels in all three patients. Pancytopenia was seen in one patient, but other laboratory studies of the hepatic and renal parameters were normal. The total lymphocyte count in the peripheral blood showed a mild decrease, while the lymphocyte phenotype study showed a notable increase in CD4⁺ cells and a decrease in CD8⁺ cells, with an elevation of a 4/8 ratio, in all cases during therapy. One patient relapsed with pelvic recurrence 14 months after the initiation of therapy, but the other two patients are still in remission 25 and 22 months after the initiation of therapy.