Clinical value of tumour markers and serum-ascites albumin gradient in diagnosis of malignant ascites

Abstract

Objective To investigate the clinical value of tumour markers and serum-ascites albumin gradient (SAAG) in diagnosis of malignant ascites. Methods One hundred and fourteen patients with ascites, who were admitted to the hospital between Jan. 2005 and Jan. 2008, were retrospectively reviewed. The patients were divided into malignant (n = 39) or benign (12 with tuberculosis and 93 with aseptic liver cirrhosis) ascites groups according to the etiology. The distribution of tumor markers (CEA, CA19-9 and CA125) and SAAG in both groups were analyzed and receiver operating characteristic (ROC) was constructed. Results The tumor markers and SAAG were found both in malignant ascites group and benign ascites group. The concentrations of CEA and CA19-9 in serum and ascites were higher in malignant ascites group than in benign ascites group. The SAAG in malignant ascites group was significantly lower than that in patients with liver cirrhosis (P 0. 05). There was no difference in level of CA125 in serum or ascites between malignant ascites group and benign ascites group (P>0.05). The area under the curve of ascitic fluid CEA, CA19-9 and SAAG were 0.79, 0.82 and 0.85, respectively. The cutoff values of ascitic fluid CEA, CA19-9 and SAAG were optimally chosen at 1.45 μ/L, 19.50 μ/L and 13. 50 g/L, respectively. The sensitivity and specificity were 66.7% and 78.1% in CEA, 74.4% and 84.8% in CA19-9, as well as 82.9% and 84.6% in SAAG.The combination of ascitic fluid CA19-9 with SAAG could increase the specificity to 97.14%, but decrease the sensitivity to 61.54%. Conclusion It is feasible to achieve optimum combination of biochemical indicators using ROC in differential diagnosis of malignant ascites from benign ascites. Key words: Ascites; Tumor markers; Receiver operating characteristics curve