Feasibility of α-fetoprotein as a diagnostic tool for hepatocellular carcinoma in Korea

BACKGROUND/AIMS The aim of this study was to evaluate the feasibility of α-fetoprotein (AFP) as a diagnostic tool for hepatocellular carcinoma (HCC) in Korean patients. METHODS We retrospectively reviewed the medical records of HCC and cirrhosis patients at three hospitals. For each HCC patient, a cirrhosis patient matched for age, sex, etiology, and Child-Pugh classification was selected by simple random sampling. The performance of AFP in the diagnosis of HCC was determined using receiver operating characteristic curve analysis. RESULTS A total of 732 patients with HCC or cirrhosis were selected for each case and the control groups. The mean age was 54 years, and 72.4% of patients were male. The mean serum AFP levels in the HCC group and cirrhosis group were 3,315.6 and 117.2 ng/mL, respectively (p < 0.001). The area under the receiver operating characteristic curve for all HCC patients was 0.757. The sensitivity, specificity, and positive predictive value of AFP was 50.55%, 87.70%, and 80.43%, respectively, at a cut-off of 20 ng/mL; 37.70%, 95.90%, and 90.20%, respectively, at a cut-off of 100 ng/mL, and 30.05%, 97.27%, and 91.67%, respectively, at a cut-off of 200 ng/mL. A cut-off of 100 ng/mL was more sensitive than one of 200 ng/mL with equivalent specificity and positive predictive value. CONCLUSIONS The cut-off AFP value for early-stage HCC was 17.4 ng/mL. Our study cautiously suggests that AFP has a role in the diagnosis of HCC, and that the appropriate value of AFP for the diagnosis of HCC may be 100 ng/mL rather than 200 ng/mL.