Value of serum and biliary carcinoembryonic antigen, carbohydrate antigen 19-9, and carbohydrate antigen 24-2 in diagnosis of benign and malignant biliary obstructive diseases

Objective To investigate the value of serum and biliary carcinoembryonic antigen (CEA) , carbohydrate antigen 19-9 (CA19-9) , and carbohydrate antigen 24-2 (CA24-2) in the diagnosis of benign and malignant biliary obstructive diseases.Methods A total of 40 patients with benign biliary obstructive diseases and 40 with malignant ones, who were diagnosed and treated in The Central Hospital of Enshi Autonomous Prefecture from June 2015 to December 2016, were enrolled.Serum samples collected on admission and bile samples collected during surgery were used to measure the levels of tumor markers CEA, CA19-9, and CA24-2.The t-test was used for comparison between two groups, and a receiver operating characteristic (ROC) curve analysis was performed for each tumor marker in the diagnosis of benign and malignant biliary obstructive diseases.Results Compared with the benign group, the malignant group had significantly higher serum levels of CA19-9 and CA24-2 (t = 5.899 and 3.223, both P < 0.05) and biliary levels of CEA, CA19-9, and CA24-2 (t =3.304, 7.615, and 7.279, all P < 0.05) .In the patients with malignant biliary obstructive diseases, the levels of CEA, CA19-9, and CA24-2 in the bile were significantly higher than those in serum (t = 3.297, 4.975, and 3.993, all P < 0.05) .Biliary CA24-2 had the highest Youden index (0.75) and area under the ROC curve (AUC) (0.946) ; biliary CA19-9 had a Youden index of 0.74 and an AUC of 0.937, and serum CA19-9 had a Youden index of 0.68 and an AUC of 0.898.These three indices had a relatively high diagnostic value.Combined measurement of biliary CA24-2, serum CA19-9, and biliary CA19-9 had a sensitivity of 94.75%, a negative predictive value of 93.50%, and a Youden index of 0.82 in the diagnosis of malignant biliary obstructive diseases.Conclusion Biliary tumor markers have a great value in the diagnosis of malignant biliary obstructive diseases, and the combined measurement of biliary CA24-2, serum CA19-9, and biliary CA19-9 has the highest value in the differential diagnosis of benign and malignant biliary obstructive diseases.