Immunolocalisation of PIVKA-II in paraffin-embedded specimens of hepatocellular carcinoma.

Aims/background: Although serum PIVKA-II has been widely used as a tumor marker for hepatocellular carcinoma (HCC), little information is available concerning tissue PIVKA-II, and detection of tissue PIVKA-II in paraffin-embedded tissue specimens of HCC is also considered difficult.
Methods: Paraffin-embedded HCC tissues obtained at autopsy from 22 patients were subjected to immunohistochemical staining using the antibody MU-3 (Eisai Co., Ltd.) after microwave antigen retrieval.
Results: PIVKA-II was mainly detected in the cytoplasm of HCC cells. The intensity of tissue PIVKA-II staining was not correlated with serum PIVKA-II levels or with the histotogical differentiation of HCC. However PIVKA-II staining tended to be more intense in tissue from patients with portal tumor thrombus, distant metastases, or a longer duration of HCC.
Conclusion: This method of immunohistochemical staining is easy and simple to use and may be helpful for detecting tissue PIVKA-II in paraffin-embedded HCC specimens.