[Effect of surgical treatment on the natural killer activity in lung cancer patients].

The NK activity was studied in 15 male patients with stage III of the lung cancer. All patients underwent operation. The NK activity was tested against H3 uridine-labeled K-562 tumour cells in the 4-hour cytotoxic test before and 8-14 days after the surgery. As control 15 healthy men were tested. The NK activity of mononuclear cells of the peripheral blood and nonadherent lymphocytes in the lung cancer patients before surgery was significantly decreased (P less than 0.001). Surgery did not affect essentially the NK activity. The removal of monocytes from the mononuclear cell suspension of the peripheral blood caused enhancement of the NK activity only in the postoperative period (P less than 0.05). Survival of the patients did not correlate with the cytotoxic activity of the NK cells before (r = 0.071) and after surgery (r = 0.275). The postoperative cytotoxic activity of NK cells correlated better with survival of the patients.