Adverse effects of intraportal chemotherapy on natural killer cell activity in colorectal cancer patients

Background: Adjuvant intraportal chemotherapy has been used with a view to prevent the development of metachronous hepatic metastases following curative resection for colorectal cancer. To evaluate the effects of this therapy on systemic antitumor immunological activity, 35 colorectal cancer patients who underwent curative resection were investigated. Method: Among them, 19 had adjuvant intraportal chemotherapy with mitomycin C and 5-fluorouracil (treated group) and 16 had no chemotherapy (untreated group). Natural killer (NK) cell activity, lymphocyte subpopulations, and immunosuppressive acidic protein (IAP) in the peripheral blood were measured serially before and after operation, and the values were compared between the two groups. Result: The NK cell activity and the percentages of CD16 positive and CD56 positive cells were markedly reduced in the treated group postoperatively. Significant difference was also observed between the two groups on the 4th postoperative day in regard to NK cell activity and CD56 positive cells. Conclusions: Intraportal chemotherapy in our study reduced the NK cell activity and its population in the peripheral blood. (C) 1997 Wiley-Liss, Inc.