DING-SHINN CHEN
To evaluate the role of plasma des-y-carboxyprothrombin in the early diagnosis of hepatocellular carcinoma, we simultaneously studied both des-y-carboxyprothrombin activities by staphylocoagulase method and des-y-carboxyprothrombin antigen levels by enzyme immunoassay in 39 patients with early stage hepatocellular carcinoma (tumor size <3 cm in 21 patients, 3 to 5 cm in 18 patients); 68 patients had large hepatocellular carcinoma and 54 patients had chronic hepatitis or cirrhosis. Des-y-carboxyprothrombin levels by staphylocoagulase method (X) and enzyme immunoassay method (Y) on the same plasma specimens of hepatocellular carcinoma patients showed a linear correlation (Y = 0.15X -10.5, r = 0.533, n = 67, p < 0.001). Elevated des-y-carboxyprothrombin activities were present in 10 of 21 patients (47.6%) with hepatocellular carcinoma (3 cm, 66.7% of 18 with hepatocellular carcinoma 3 to 5 cm, 67.6% of 68 with hepatocellular carcinomas >5 cm and 27.8% of 54 with chronic hepatitis or cirrhosis. The plasma des-ycarboxyprothrombin levels did not correlate with the tumor size or serum a-fetoprotein levels. Plasma des-ycarboxyprothrombin and serum a-fetoprotein measurements were comparable in the diagnosis of hepatocellular carcinoma because 22 (56.4%) and 21 (53.8%) of 39 patients with hepatocellular carcinoma <5 cm had increased des-y-carboxyprothrombin and a-fetoprotein levels, respectively. Up to 77% had an abnormal elevation in either marker. The des-y-carboxyprothrombin antigen levels by enzyme immunoassay method are more specific to hepatocellular carcinoma than des-ycarboxyprothrombin activities by the staphylocoagulase method the positive rates of elevated des-ycarboxyprothrombin antigen levels in the patients with hepatocellular carcinoma <3 cm, 3 to 5 cm, >5 cm and chronic hepatitis or cirrhosis were 19.0%, 55.6%, 66.2% and 14.8%, respectively. We conclude that des-y-