Superoxide anion-generating activity of polymorphonuclear leukocytes and monocytes in patients with lung cancer.

Superoxide anion (O2-) production by polymorphonuclear leukocytes (PMN) and monocytes (MN) was measured in the peripheral blood of 70 patients with lung cancer. The O2- production by these cells was decreased in many, but not all, patients. The incidence of patients with lower O2- production increased as the stage advanced. The correlation between O2- production by these cells and peripheral blood smears was evaluated in patients with cancer. Patients with 80% granulocytes and 40% monocytes or more in their peripheral blood had a significantly lower O2- production by PMN and MN compared with those with less than 80% granulocytes and 40% monocytes, respectively. These results indicate that an abnormally increased number of granulocytes and monocytes in the peripheral blood of patients with cancer may depress immunoregulatory function. In addition, decreased O2- production by these cells should be considered when assessing the defense mechanisms and susceptibility to infection of these patients.