대한대장항문학회

Natural cytotoxicity mediated by natural killer (NK) cells is believed to play an important role in host anticancer defense mechanisms. The aim of this study is to compare the number of NK cells in patients with colorectal cancer and hemorrhoids, and<br>before and after surgery in patients with colorectal cancer. Twenty colorectal cancer patients and twenty hemorrhoid ones were studied. Venous blood samples were obtained preoperatively, and on the 7th, and 14th postoperative days. Mononuclear cells<br>were isolated over Ficoll-Hypaque gradients, and T cells, B cells, and NK cells were measured with CD3 FITC (T cell), CD 19 PE (B cell), and CD56 FITC (NK cell) antibody, The number of T cell (/mm<sup>3</sup>) was 1224, 1280, and 1125 at preoperative,<br>7th, and 14th postoperative day in hemorrhoid patients and 1195, 901, and 1060 in colorectal cancer patients respectively. The number of B cell (/mm<sup>3</sup>) was 243, 160, and 250 in hemorrhoid patients and 147, 78, and 113 in colorectal cancer<br>patients. The number NK cell (/mm<sup>3</sup>) was 148, 156, and 143 in hemorrhoid patients and 129, 85, and 128 in colorectal cancer patients. There was no difference among Dukes stages in the number of NK cells. In conclusion, the number of NK cells<br>was not changed in colorectal cancer patients compared with hemorrhoid ones. Major operation changed the number of NK cells in colorectal cancer patients.<br>