Clinical Diagnostic Value for Colorectal Cancer Based on Serum CEA, CA24-2 and CA19-9

Background: To explore the clinical value of a combined detection of serum concentration of carcinoembryonic antigen (CEA), carbohydrate antigen 24-2 (CA24-2), and carbohydrate antigen 19-9 (CA19-9) for colorectal cancer (CRC). Methods The levels of serum tumor markers (CEA, CA24-2 and CA19-9) and clinical characteristics in patients with colorectal cancer were evaluated. In addition, KRAS/NRAS/PIK3CA/BRAF mutations were detected in some patients with colorectal cancer. Results A total of 2,281 patients were recruited in the study, included 1,578 colorectal cancer patients and 703 controls. The levels of CEA, CA24-2 and CA19-9 in colorectal cancer group was significantly higher than control group. The sensitivities of three individual markers were lower than 30%, which individual sensitivity of the tumor markers sorted in descending order was CEA>CA19-9>CA24-2. The specificities of three individual markers were more than 92%, and the specificity sorted in descending order was CA24-2>CA19-9>CEA. The combination of CEA+CA19-9+CA24-2 ranked the highest in sensitivity index and specificity index for colorectal cancer diagnosis. The prediction equation excluding the risk of colorectal cancer was. Probability (normal) = Exp (-5.47 - 0.28CEA - 0.11 CA242 + 0.001 CA199)/ (1+ Exp (-5.47 - 0.28CEA - 0.11 CA242 + 0.001 CA199)). There were no significant differences in age, gender, histology type, differentiation, depth of invasion and TNM stage between mutations in KRAS/NRAS, BRAF and PIK3CA genes or not, respectively. Conclusions Serum CEA, CA24-2, and CA19-9 are valuable noninvasive indicators for prediction the risk of colorectal cancer. We need to look for other, more sensitive tumor markers.