Tumor Markers in Serum and Ascites in the Diagnosis of Benign and Malignant Ascites

OBJECTIVE: To evaluate the values of 4 tumor markers in serum and ascites and their ascites/serum ratios in the identification and diagnosis of benign and malignant ascites. MATERIALS AND METHODS: A total of 76 patients were selected as subjects and divided into malignant ascites group (45 cases) and benign ascites group (31 cases). Samples of ascites and serum of all hospitalized patients were collected before treatment. The levels of carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), cancer antigen 125 (CA125) and carbohydrate antigen 19-9 (CA19-9) were detected by chemiluminescence (CLIA) . RESULTS: CEA, AFP and CA19-9 in both serum and ascites as well as CA125 in ascites were evidently higher in the malignant ascites group than in the benign ascites group (P<0.01). Malignant ascites was associated with elevated ascites/serum ratios for AFP and CA125 (P<0.01). The areas under receiver operating characteristic (AUROCs) of CEA and CA125 in ascites and the ratios of ascites/serum of AFP, CEA, CA125 and CA19-9 were all >0.7, suggesting certain values, while those of ascites CA19-9 and serum CEA were 0.697 and 0.629 respectively, indicating low accuracy in the identification and diagnosis of benign and malignant ascites. However, the AUROCs of the remaining indexes were <0.5, with no value for identification and diagnosis. Compared with single index, the sensitivity of combined detection increased significantly (P<0.05), in which the combined detection of CEA, CA19-9 and CA125 in ascites as well as the ratio of ascites/serum of CEA, CA19-9, CA125 and AFP had the highest sensitivity (98.4%) but with relevantly low specificity. Both sensitivity and specificity of combined detection should be comprehensively considered so as to choose the most appropriate index. CONCLUSIONS: Compared with single index, combined detection of tumor markers in serum and ascites can significantly improve the diagnostic sensitivity and specificity.