"Activated" monocytes in gastric cancer patients. I. Increased Fc receptor expression, antibody-dependent cellular cytotoxicity and NBT reduction.

The Fc receptor expression, antibody-dependent cellular cytotoxicity (ADCC), and nitro-blue tetrazolium (NBT) reduction of peripheral blood monocytes from 150 patients with different stages of gastric cancer was assessed and compared with results obtained in 77 normal persons and 104 patients with non-malignant diseases of the gut. Monocytes of cancer patients showed an increased ability to form rosettes with human 0, Rh + erythrocytes coated with D-specific antibody. ADCC and NBT reduction were also elevated but no correlation was found with the stage of disease. However, all these phenomena were related to the tumor load as elevated values were the same 4-6 months after surgery in the unresectable-tumor group, while they decreased in patients with resectable tumors. These observations suggest that monocytes of some cancer patients are functionally altered ("activated") in the course of disease.