Clinical value of tumour markers and serum‐ascites albumin gradient in the diagnosis of malignancy‐related ascites

Abstract

To determine the clinical value of tumour markers in the diagnosis of malignancy-related ascites (not including hepatocellular carcinoma), serum and ascitic fluid levels of carcinoembryonic antigen, cancer antigen 125, carbohydrate antigen 19-9, tissue polypeptide antigen and serum-ascites albumin gradient were determined in 66 patients with cirrhotic ascites, 28 patients with hepatocellular carcinoma and ascites, and 29 patients with malignancy-related ascites. Three tumour markers and serum-ascites albumin gradient showed significant difference between patients with malignancy-related ascites and those without: serum carcinoembryonic antigen (26.4 +/- 31.5 vs 4.8 +/- 4.6 ng/mL, P < 0.01), ascitic fluid carcinoembryonic antigen (118.4 +/- 196.5 vs 2.0 +/- 1.4 ng/mL, P < 0.01), ascitic fluid carbohydrate antigen 19-9 (12,933 +/- 25,496 vs 23 +/- 67 U/mL, P < 0.01) and serum-ascites albumin gradient (1.1 +/- 0.4 vs 2.0 +/- 0.4 g/dL, P < 0.01). At the best cut-off levels chosen from near 95% of the data in those without malignancy-related ascites, the sensitivity, specificity and accuracy to diagnose malignancy-related ascites were, respectively, 65.5%, 93.6%, 87.0% using serum carcinoembryonic antigen > or = 10 ng/mL; 69.0%, 94.7%, 88.6% using ascitic fluid carcinoembryonic antigen > or = 5 ng/mL; 65.5%, 93.6%, 87.0% using ascitic fluid carbohydrate antigen 19-9 > or = 50 U/mL; 62.1%, 98.9%, 90.2% using serum-ascites albumin gradient < 1.1 g/dL. Although serum-ascites albumin gradient offered the best diagnostic accuracy and specificity, its sensitivity was not good enough. Our study indicates that serum-ascites albumin gradient and tumour markers are not sensitive parameters in the diagnosis of malignancy-related ascites.

Correlation of Tumour Markers in Ascitic Fluid and Serum: Are Measurements of Ascitic Tumour Markers a Futile Attempt?

“…In fact some studies have concluded that the measurement of ascitic tumour markers does not improve the discriminative ability of malignant effusions. 7,8,15,20 Nevertheless, the present study found that AFP levels were higher in serum than in ascitic fluid and this agrees with the view that AFP levels are always higher in serum than in ascites and are much more sensitive than ascitic cytology in detecting hepatocellular carcinoma. 2 Benign diseases, especially liver cirrhosis, tuberculous peritonitis or nephrotic syndrome have also been the focus for ascitic fluid tumour marker analysis.…”

Biochemical analysis of ascitic (peritoneal) fluid: what should we measure?

“…50,57,58 However, Chen et al 59 reflected that although SAAG offered the best diagnostic accuracy (90.2%) and specificity (98.9%) for the diagnosis of malignancy, its sensitivity of 62.1% was too low.…”

CEA, AFP and CA 19-9 analysis in peritoneal fluid to differentiate causes of ascites formation

“…Analysis was performed using tumor marker cut-offs that achieved high specificity to reduce false positives that might lead to additional unnecessary testing; as a consequence, the sensitivities were lower than previous reports [5,14,15]. Using this approach, measurement of tumor markers did not show improved sensitivity over cytology when all malignancies were included.…”