Functional abnormalities of neutrophils in cancer patients : inefficient phagocytosis and reverse endocytosis.

A study of neutrophil functions has been performed in 17 patients with advanced cancer and in 21 controls. Their phagocytic activity, their index of reduction of NBT and their myeloperoxidase activity were examined. The reslts suggest that cancer patients might have a "factor" or "factors" in their plasma which interfereu (s) with phagocytosis and which promote (s) exocytosis of lysosomal enzymes ("reverse endocytosis") from from autologous polymorphonuclear leucocytes as well as from cells obtained from normal healthy donors.