Clinical Value of Serum CEA, CA24-2 and CA19-9 in Patients with Colorectal Cancer

Background: To investigate the clinical value of serum concentration of carcinoembryonic antigen (CEA), carbo-hydrate antigen 24-2 (CA24-2), and carbohydrate antigen 19-9 (CA19-9) in the detection of colorectal cancer (CRC). Methods: The serum levels of tumor markers and KRAS/NRAS/PIK3CA/BRAF gene mutations were detected in patients with colorectal cancer. Clinical medical records in colorectal cancer patients were collected. Results: A total of 2,281 patients were recruited in the study, included 1,578 colorectal cancer patients and 703 controls. CEA, CA24-2, and CA19-9 concentrations were significantly higher in the colorectal cancer group than in the control group. The sensitivity of these tumor markers sorted in descending order was CEA>CA19-9>CA24-2. The best specificity was CA24-2, followed by CA19-9 and CEA, with all were more than 92%. The combination of CEA, CA19-9, and CA24- 2 ranked the best sensitivity and specificity for colorectal cancer diagnosis. The prediction equation excluding the risk of colorectal cancer was. Probability (normal) = Exp (-5.47 - 0.28*CEA - 0.11* CA242 + 0.001*CA199)/(1+ Exp (-5.47 - 0.28*CEA - 0.11*CA242 + 0.001*CA199)). Besides, there were no significant differences in age, gender, histology type, differentiation, depth of invasion, and TNM stage in KRAS/NRAS, BRAF, and PIK3CA mutations compared with wild type. Conclusions: Serum CEA, CA24-2, and CA19-9 are valuable indicators for predicting the risk of colorectal cancer.