Diagnosis of malignant ascites. Comparison of ascitic fibronectin, cholesterol, and serum-ascites albumin difference.

The ascitic fluid concentrations of cholesterol and fibronectin and the serum-ascites albumin difference were compared with two conventional tests of ascitic fluid, total protein and LDH, in their diagnostic ability for detection of malignancy in ascitic samples from 69 patients with ascites: 54 with ascites due to liver disease and 15 whose ascites was caused by peritoneal metastases. Sixteen cirrhotic patients with superimposed hepatocellular carcinoma in whom ascites was of uncertain etiology were considered separately. The mean ascitic fluid total protein, LDH, cholesterol, and fibronectin values in the peritoneal metastases group were 3.70 +/- 1.20 g/dl, 247.26 +/- 148.14 units/liter, 109.06 +/- 29.85 mg/dl, and 91.57 +/- 41.52 micrograms/ml, respectively, and all were significantly higher than the corresponding values in the liver disease group (P less than 0.001), which were 1.37 +/- 0.59 g/dl, 75.40 +/- 110.70 units/liter, 23.75 +/- 11.22 mg/dl, and 31.86 +/- 10.51 micrograms/ml, respectively. Mean serum-ascites albumin difference in the peritoneal metastases group was 0.62 +/- 0.38 g/dl, which was significantly different from the corresponding value in the liver disease group (1.92 +/- 0.41 g/dl, P less than 0.001). Both ascitic cholesterol above 46 mg/dl and an ascitic fibronectin concentration greater than 50 micrograms/ml had high diagnostic accuracy (97%) for malignancy, being higher than that achieved using a serum-ascites albumin difference under 1.1 g/dl and an ascitic total protein above 2.5 g/dl, which had accuracies of 94% and 93%, respectively. Ascitic fluid LDH was the least reliable test. No differences in the ascitic fluid analysis were found between cirrhotic patients with and without hepatocellular carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)