Immunohistochemical study of protein induced by vitamin K absence or antagonist II in hepatocellular carcinoma

Background and Objectives: Protein induced by vitamin K absence or antagonist II (PIVKA-II) has been used as a tumor marker of hepatocellular carcinoma (HCC). In this study, we examined the expressions of PIVKA-II in HCC tissues. Methods: Expression of PIVKA-II in HCC was evaluated with the avidin-biotin-peroxidase complex method. Paraffin-embedded HCC tissues obtained from 48 patients were subjected to immunohistochemical staining using the anti-PIVKA-II antibody monoclonal antibody (MU-3) (Eisai, Tokyo, Japan). Results: The tissue PIVKA-II positivity rate of 12/23 (52.2%) in HCC with vascular infiltration was significantly higher than the rate of 4/25 (16.0%) in HCC without such infiltration. Further, the tissue PIVKA-II positivity rate of 13/28 (46.4%) in HCC of tumor stage III or IV was significantly higher than the rate of 3/20 (6.0%) in HCC of tumor stage I or II. Overall survival rate tended to be lower in the tissue-PIVKA-II-positive than -negative patients. Conclusions: PIVKA-II may play an important role in progression of HCC and is useful not only as a tumor marker but also as a prognostic factor. (C) 2003 Wiley-Liss, Inc.