Serum alpha-fetoprotein for diagnosis of hepatocellular carcinoma in patients with chronic liver disease: influence of HBsAg and anti-HCV status

Background: It is not established whether virological status affects the ef ficency of alpha -fetoprotein (AFP) as a hepatocellular carcinoma (HCC) mar ker among patients with chronic liver disease (CLD). Methods: We enrolled in a case-control study 170 HCC and 170 CLD patients, matched for age, sex, CLD and HBsAg/anti-HCV status. The AFP sensitivity, s pecificity, positive (PPV) and negative (NPV) predictive values were calcul ated. PPV and NPV were evaluated for three additional HCC prevalences (5, 1 0, and 20%). Results: The best discriminating AFP value was 16 ng/ml. A value of 20 ng/m l (above which investigations for HCC are recommended) had equivalent sensi tivity (60.0 vs. 62.4%) and specificity (90.6 vs. 89.4%). PPV of 20 ng/ml w as 84.6% but decreased to 25.1% at 5% tumor prevalence. NPV was 69.4% and r ose to 97.7% at 5% prevalence. In the different groups of infected patients PPV ranged from 80.0 to 90.9%, falling to 17.4-34.5% at 5% prevalence. In non-infected patients PPV was 100% at any HCC prevalence. NPV ranged from 5 9.0 to 73.0%, reaching 96.5-98.1% at 5% prevalence. Conclusions: In CLD patients, AFP monitoring misses many HCCs and inappropr iately arouses suspicion of malignancy in many patients. Its usefulness is barely affected by the infection responsible for CLD. An AFP elevation coul d be more indicative of HCC in non-infected patients. (C) 2001 European Ass ociation for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved.