The association between specific nutritional antioxidants and manifestation of colorectal cancer.

Determination of specific antioxidants for examination of oxidative balance and immune responses may be of value in the early diagnosis of colorectal cancer. In the present report, we investigated urinary excretion of zinc, copper, and neopterin and serum levels of vitamins A, C, and E in 30 patients (age = 64 +/- 12 y) with colorectal cancer at the time of diagnosis and in 30 control subjects (age = 61 +/- 11 y) with benign disorders not associated with a systemic inflammatory response. Urinary excretion of zinc, copper, and neopterin was significantly elevated, and serum concentration of vitamin A was decreased in patients with colorectal cancer; these changes are characteristics of systemic immune activation. These phenomena may be of use for the detection of tumor progression and immune response to neoplasm.