[Optimal cut-off value of PIVKA-II for diagnosis of hepatocellular carcinoma--using ROC curve].

Optimal Cut-off Value of PIVKA-II for Diagnosis of Hepatocellular Carcinoma Using ROC Curve Myong Jin Kim, M.D., Kang Woo Bae, M.D., Pyoung Ju Seo, M.D., In Kook Jeong, M.D., Jung Hyuk Kim, M.D., Bo Han Lee, M.D., Ki Tae Bang, M.D., Dong Woo Kim, M.D., and Il Han Song, M.D. Department of Internal Medicine, Dankook University College of Medicine, Choenan, Korea Background/Aims: Protein induced by vitamin K absence or antagonist-II (PIVKA-II), also known as des-carboxyprothrombin (DCP), can be used as an alternative tool to alpha-fetoprotein (AFP) for surveillance of hepatocellular carcinoma (HCC). The aims of the present study were to compare PIVKAII levels between the patients with HCC and patients with non-HCC chronic liver disease, to evaluate the correlation of PIVKA-II and AFP in HCC patients, and finally to estimate the optimal cut-off value for PIVKA-II for the diagnosis of HCC with using the receiver operating characteristic (ROC) curve. Methods: A total of 227 consecutive patients with HCC (n=42) or chronic liver disease (n=185) were enrolled in this study. HCC was diagnosed histologically or by imaging such as computed tomography, magnetic resonance imaging or angiography. The serum PIVKA-II and AFP levels were measured by electrochemiluminoimmunoassay with using the Haicatch PIVKA-II kit and by immunoradiometric assay, respectively. Results: The PIVKA-II level in the HCC patients was significantly higher than the non-HCC chronic liver disease patients (903.0±1156.7 vs. 111.7±211.0 mAU/ mL, respectively, P<0.01). PIVKA-II and AFP showed a statistical correlation in HCC patients (r=0.46, P<0.01). The sensitivity and specificity of PIVKA-II for the diagnosis of HCC were 66.7% and 74.1%, respectively, and when tasted together with AFP, the sensitivity was increased by 85.7%. For the ROC curve of PIVKA-II in HCC patients, the specificity of a 250 mAU/mL level of PIVKA-II was 95%. Conclusions: PIVKA-II was as useful surveillance tool for differentiating HCC from chronic liver disease, and a PIVKA-II value of 250 mAU/ mL was proposed as a significant cut-off value for diagnosis of hepatocellular carcinoma. (Korean J Hepatol 2006;12:404-411)