Immunocytochemical increased evidence of inducible nitric oxide synthase, tumor necrosis factor-alpha, and adrenocorticotropic hormone in human peritumoral lymph nodes.

In the current study, mesenteric and peritumoral lymph nodes surgically removed from patients with colon-rectum cancer were studied. Morphologic and immunocytochemical investigations demonstrated that mesenteric (control) and peritumoral lymph nodes of a same patient showed the same morphologic structure, but a different immunocytochemical pattern. Indeed, an increased immunoreactivity to anti-inducible nitric oxide synthase, anti-tumor necrosis factor-alpha, and anti-adrenocorticotropic hormone antibodies in the lymphatic tissue of peritumoral lymph nodes compared with mesenteric lymph nodes was observed. These findings suggest that in colon-rectum cancer, the pathologic event induces an increased expression of the molecules involved in the processes of inflammation and carcinogenesis that occurs earlier than the appearance of morphologic modifications.