A Prospective Study of Serum Carcinoembryonic Antigen in Patients with Newly Diagnosed Colorectal Cancer and Healthy Individuals

Abstract

Aims: Studies have shown that serum levels of tumor markers are influenced by several factors. The present study has assessed the effect of smoking, age, sex and on elevated levels of carcinoembryonic antigen (CEA) among the healthy individuals, and has compared it in patients with newly diagnosed colorectal cancer. Methods: Our experimental study was conducted on 800 cases in Iran. We had two parallel groups including 675 normal cases and 125 patients with colorectal cancer. The quantitative measurement of CEA for the recruited individuals was carried out by RIA method. Results: We observed the distribution of CEA values was significantly higher in colorectal cases than apparently healthy cases (P<0.001). Also the distribution of CEA values was found to be significantly higher in the healthy smokers group when compared to the healthy nonsmokers (P<0.05). Comparison among mean of CEA levels in three age groups including individuals with mean age under 30 years, between 30 and 60 years and upper 60 years old respectively as groups 1, 2 and 3 showed significantly elevated CEA levels in over 60 years individuals (P<0.05). Conclusions: This study indicated that among all disagreements about CEA validity as a beneficial tool for clinicians, they should be aware of the usefulness of the CEA level in serum but even a very high CEA level should not be considered by itself as evidence of cancer.