Table 1.

Immunohistochemical markers of HCC.

Marker	Staining Pattern	Characteristics
Markers of Hepatocellular Differentiation
Hepatocyte paraffin 1	Cytoplasmic	The sensitivity decreases in the diagnosis of poorly differentiated HCC and scirrhous HCC.
Arginase-1	Cytoplasmic with variable nuclear reactivity	This is the most sensitive marker of HCC and shows high sensitivity even in poorly differentiated HCC and scirrhous HCC.
pCEA	Canalicular	The sensitivity decreases in poorly differentiated HCC. The staining may be difficult to interpret.
CD10	Canalicular	The sensitivity tends to be lower compared to pCEA.
Markers of Malignant Hepatocytes
Glypican-3	Cytoplasmic, membranous, and canalicular	The sensitivity is low in well differentiated HCC and high in moderately and poorly differentiated HCC.
Heat shock protein 70	Nuclear and cytoplasmic	The staining pattern is usually patchy. Benign hepatocytes may be stained.
Glutamine synthetase	Cytoplasmic	This cannot be used in the differential diagnosis between HCC and HCA, and between hepatocellular and non-hepatocellular neoplasms.
α-Fetoprotein	Cytoplasmic	The sensitivity is low.
CD34	Sinusoidal	The evaluation is subjective.

HCA, hepatocellular adenoma; HCC, hepatocellular carcinoma; pCEA, polyclonal carcinoembryonic antigen.