The neutrophil and lymphocyte nonspecific esterase in patients with malignancies

In 52 patients with malignancies such as lung cancer, carcinoma of the stomach, and cancer of the colon (25, 18, and 9 cases, respectively) activity and intracellular localization of alpha-naphthyl acetate esterase has been evaluated by means of semiquantitative cytochemical method. Patients with advanced metastatic process occurring during clinical evolution of those malignancies showed decreased activity of above enzyme within the peripheral blood neutrophils and decreased numbers of enzyme-positive lymphocytes having intact enzyme-positive lysosomal granules. The authors discuss the significance of that observation in relation to the enzymatic alterations of cells during antitumor response of immune system.