Hep Par 1, Hepatocyte Paraffin 1

Hep Par 1 is a monoclonal antibody, clone OCH1E5.2.10. The antigen detected by Hep Par 1 does not appear to be an oncofetal antigen or tumour-associated antigen. There is preliminary evidence that it is associated with the membrane of hepatocyte mitochondria2 but absent from the mitochondria of other tissues.

The antibody is effective on formalin-fixed, paraffin embedded tissues. Antigen retrieval using high pH buffer and a detection kit which minimizes or eliminates non-specific biotin reactivity is recommended4. Staining is cytoplasmic and granular, without canalicular or zonal accentuation4.

Immunohistochemical expression


columnar lined oesophagus without intestinal metaplasia



columnar lined oesophagus with intestinal metaplasia


chronic gastritis with intestinal metaplasia



hepatocellular carcinoma

30/321, 37/382, 289/2903, 17/215, 9/106, 12/127, 33/408, 6/910, 18/1911 , 39/4212, 88/9613, 50/7615


12/1214, 1/15

metastatic adenocarcinoma, NOS

0/131, 1/185, 0/75 15

biliary tract carcinoma

4/321, 2/352, 3/65, 0/38, 1/1413

mixed hepatocellular carcinoma / cholangiocarcinoma


pancreatic carcinoma

3/122, 0/88, 1/1313

breast carcinoma

0/92, 0/68, 0/913

oesophageal adenocarcinoma


gastric carcinoma

3/102, 10/1012, 4/1313, 1/815, 4/1316

small intestinal carcinoma


colon carcinoma

0/82, 1/108, 8/10411, 0/1013

lung carcinoma

0/52, 1/108, 3/5511, 0/612, 5/2113

endometrial carcinoma

0/32, 0/1013

ovarian carcinoma

0/72, 5/4011, 4/2413

uterine cervix


prostatic carcinoma

0/42, 0/713

renal carcinoma

0/52, 0/106, 0/512, 0/1013, 0/7415

hepatoid adenocarcinoma

6/79, 2/610

hepatoid yolk sac tumour


adrenocortical carcinoma

3/1311, 0/812, 0/1013, 0/2115

small cell carcinoma of lung and skin


salivary gland


germ cell


yolk sac tumour


urinary bladder

0/12, 1/1012, 0/1513

vascular liver tumour





0/32, 0/1613

neuroendocrine carcinoma

0/142, 0/135, 4/913





testicular tumours


skin, basal cell carcinoma


skin, Merkel cell carcinoma


skin, squamous cell carcinoma


epithelioid sarcoma







Diagnostic utility


1 Leong, A. S., Sormunen, R. T., Tsui, W. M., Liew, C. T. Hep Par 1 and selected antibodies in the immunohistological distinction of hepatocellular carcinoma from cholangiocarcinoma, combined tumours and metastatic carcinoma. Histopathology 1998;33:318-324.

2 Wennerberg, A. E., Nalesnik, M. A., Coleman, W. B. Hepatocyte paraffin 1: a monoclonal antibody that reacts with hepatocytes and can be used for differential diagnosis of hepatic tumors. Am J Pathol 1993;143;1050-4.

3 Wu, P. C., Fang, J. W., Lau, V. K., Lai, C. L., Lo, C. K., Lau, J. Y. Classification of hepatocellular carcinoma according to hepatocellular and biliary differentiation markers. Clinical and biological implications. Am J Pathol 1996;149:1167-75.

4 Lamps, L.W. and Folpe, A.L. The diagnostic value of hepatocyte paraffin antibody 1 in differentiating hepatocellular neoplasms from nonhepatic tumors: a review. Adv Anat Pathol 2003;10:39-43.

5 Minervini, M.I., Demetris, A.J., Lee, R.G., Carr, B.I., Madariaga, J. and Nalesnik, M.A. Utilization of hepatocyte-specific antibody in the immunocytochemical evaluation of liver tumors. Mod Pathol 1997;10:686-92.

6 Murakata, L.A., Ishak, K.G. and Nzeako, U.C. Clear cell carcinoma of the liver: a comparative immunohistochemical study with renal clear cell carcinoma. Mod Pathol 2000;13:874-81.

7 Kumagai I et al. Immunoreactivity to monoclonal antibody, Hep Par 1, in human hepatocellular carcinomas according to histopathological grade and histologic pattern. Hepatology Research 2001;20:312-319.

8 Zimmerman, R.L., Burke, M.A., Young, N.A., Solomides, C.C. and Bibbo, M. Diagnostic value of hepatocyte paraffin 1 antibody to discriminate hepatocellular carcinoma from metastatic carcinoma in fine-needle aspiration biopsies of the liver. Cancer 2001;93:288-91.

9 Maitra, A., Murakata, L.A. and Albores-Saavedra, J. Immunoreactivity for hepatocyte paraffin 1 antibody in hepatoid adenocarcinomas of the gastrointestinal tract. Am J Clin Pathol 2001;115:689-94.

10 Pitman M et al. Hepatocyte paraffin 1 antibody cannot distinguish primary ovarian malignancies with hepatoid differentiation from metastatic hepatocellular carcinoma. Mod Pathol 2002;15:206A. (abstract)

11 Fan Z et al. HepPar-1 stain for the differential diagnosis of hepatocellular carcinoma: 613 tumors tested using tissue microarrays and conventional sections. Mod Pathol 2002;15:1178A. (abstract)

12 Muir T et al. Immunoreacitivity for hepatocyte paraffin 1 antibody in hepatic and extrahepatic tumors. Mod Pathol 2002;15:290A. (abstract)

13 Chu, P.G., Ishizawa, S., Wu, E. and Weiss, L.M. Hepatocyte antigen as a marker of hepatocellular carcinoma: an immunohistochemical comparison to carcinoembryonic antigen, CD10, and alpha-fetoprotein. Am J Surg Pathol 2002;26:978-88.

14 Fasano, M., Theise, N.D., Nalesnik, M., Goswami, S., Garcia de Davila, M.T., Finegold, M.J. and Greco, M.A. Immunohistochemical evaluation of hepatoblastomas with use of the hepatocyte-specific marker, hepatocyte paraffin 1, and the polyclonal anti-carcinoembryonic antigen. Mod Pathol 1998;11:934-8.

15 Wieczorek, T. J., J. L. Pinkus, et al. (2002). "Comparison of thyroid transcription factor-1 and hepatocyte antigen immunohistochemical analysis in the differential diagnosis of hepatocellular carcinoma, metastatic adenocarcinoma, renal cell carcinoma, and adrenal cortical carcinoma." Am J Clin Pathol 118(6): 911-21.

16 Chu, P. G., Z. Jiang, et al. (2003). "Hepatocyte antigen as a marker of intestinal metaplasia." Am J Surg Pathol 27(7): 952-9.

This page last revised 13.1.2004.

©SMUHT/PW Bishop