Evaluation of alpha-fetoprotein assay in ascitic fluid for the diagnosis of hepatocellular carcinoma

Values of simultaneous determination of 5 tumor markers in fluid and serum and their ratio in differential diagnosis of benign and malignant ascites

AIM: To evaluate the values of the simultaneous determination of tumor markers AFP, CEA, CA19-9, CA50 and CA125 in fluid and serum, and their ratio (F/S) in the differential diagnosis of benign and malignant ascites.

METHODS: Serum and ascites fluid specimens were simultaneously collected from 105 patients with ascites (benign 57, malignant 48). The tumor markers AFP, CEA were determined by electrochemoluminescence. The tumor markers CA19-9, CA50 and CA125 were measured with radioimmunoassay (RIA).

RESULTS: The F/S ratios were all lower than 1.2 in benign ascites fluid and higher than 1.2 in the majority of malignant fluid when the tumor marker content in fluid was higher than the normal cut-off of serum (AFP > 25 μg/L, CEA > 5 μg/L, CA19-9 > 37 kU/L and CA50 > 20 mg/L). The combination of a F/S ratio greater than 1.2 and a cut-off stated above showed sensitivities of 18.8%, 62.5%, 58.3% and 72.9%, respectively for AFP, CEA, CA19-9 and CA50, with a specificity of 100%, These sensitivities were significantly higher than those of a single determination of concentration in fluid or F/S ratio (16.7%, 37.5%, 29.2% and 47.9%)(P < 0.01) besides AFP. The combined sensitivity of 4 tumor markers and their F/S ratios was 91.7% with a specificity of 100%.

CONCLUSION: In comparison with either single determination of concentration in serum or fluid, the sensitivity and specificity of tumor markers AFP, CEA, CA19-9 and CA50 can be significantly increased by simultaneous determination of the concentration in fluid and their F/S ratio.

Clinical evaluation of the simultaneous determination of tumor markers in fluid and serum and their ratio in the differential diagnosis of serous effusions

We evaluated the diagnostic utility of simultaneous determination of 5 tumor markers, CEA, CA 125, CA 15-3, CA 19-9 and cytokeratin 19 (CYFRA 21-1), in fluid and serum from 101 patients, 52 with pleural effusion (22 malignant) and 49 patients with ascites (14 malignant). Tumor marker concentrations in fluid from patients with malignant effusions were significantly higher than those obtained in benign fluids or serum. However, there are two types of tumor markers: those released/secreted by normal mesothelia such as CA 125 and cytokeratin 19 (higher levels in benign fluids than in serum) and non-released/secreted tumor markers (low concentrations in benign fluids) such as CEA, CA 19-9 and CA 15-3. The fluid/serum (F/S) ratio showed better sensitivity with maximum specificity than a single determination in fluid for CEA, CA 15-3 and CA 19-9, but not for CA 125 and CYFRA. The combination of a F/S ratio greater than 1.2 and a cut-off of 5 ng/ml for CEA, 30 U/ml for CA 15-3 and 37 U/ml for CA 19-9 showed sensitivities of 58, 57 and 44%, respectively, and a specificity of 100%, with a combined sensitivity of 82% for overall effusions and 79% for fluids with negative cytology with a specificity of 100%. In conclusion, the use of the F/S ratio in nonsecreted tumor markers such as CEA, CA 19-9 and CA 15-3 improve the sensitivity and specificity and allow standardization of the cut-off.

Ascitic fluid analysis: the role of biochemistry and haematology

In specific settings, biochemical and haematological analysis of ascitic fluid may provide answers to important clinical questions. This review seeks to outline the value and limitations of ascitic fluid analysis and the main clinical scenarios in which it may be useful.