Objective: Colorectal cancer is one of the most endemic cancers causing significant health problems which decreases life quality and causes job loss. As in several cancer types, it is assumed that oxidative damage and consequent inşammation may have an effect on colorectal cancer composition and development. The aim of our study was to evaluate oxidative and nitrosative stress in colorectal cancer,and to establish its correlation with leukocyte activation.

Materials and Methods: Our study groups consisted of patients with colorectal cancer diagnosis (n=21) and healthy subjects as the control group (n=21). Serum malondialdehyde, plasma nitrotyrosine, nitric oxide and myeloperoxidase levels were determined.

Results: Serum malondialdehyde and plasma myeloperoxidase levels of the cancer group were higher than those of the control group (p<0.05 and p<0.01, respectively). The plasma nitrotyrosine and nitric oxide levels were higher in the colorectal cancer group compared to the control group ( p<0.01 for both). When the groups were evaluated separately, no correlation was determined among parameters of the control group, however a positive correlation was found between plasma nitric oxide and nitrotyrosine levels in the colorectal cancer group (r = 0.504, p<0.01).

Conclusion: ın conclusion, these findings indicate that oxidative and nitrosative stresses are effective in colorectal carcinoma.ın addition, it may be concluded that nitrosative stress may cause plasma protein oxidation.