Impairment of phagocytic and T-cell-mediated antibacterial activity and plasma endotoxins in patients with untreated gastrointestinal cancer

Background: Cancer patients have multiple immune deficits, and mediators, such as prostaglandins, transforming,growth factor-beta, and interleukin (ZL)-10, may play a role in the pathogenesis of these immune dysfunctions. Methods: Fifty-six patients with gastrointestinal cancer (11 gastric cancer; 7 papilla of Vater cancer, and 38 colorectal cancer) were enrolled for this study, before starting conventional treatments. Phagocytosis and killing exerted by polymorphonuclear cells and monocytes, peripheral blood mononuclear cell absolute numbers, T-cell-mediated antibacterial activity, serum levels of IL-10 and interferon (IFN)-gamma, and plasma bacterial endotoxin concentration were evaluated. Results: Data show an impaired phagocytic and T-cell-mediated antibacterial activity in all cancer patients, whereas only in subjects with gastric cancer were IFN-gamma serum levels reduced. Circulating endotoxins were detected in 17 patients. Conclusions: In untreated gastrointestinal cancer patients the capacity of phagocytes and T-cells to clear pathogens is reduced. This dysfunction may increase the risk of becoming infected and may account for the presence of endotoxin in 30% of patients.