title: Carcinoma, a fibrolamellar variant--immunohistochemical analysis of 4 cases.
abstract: OBJECTIVE
  To analyze, by means of immunocytochemistry, the cases of fibrolamellar variant of hepatocellular carcinoma (FLC), diagnosed in our Department.
  
  
  METHODS
  The material comprised 4 FLC cases of tumors resected surgically. Besides the routine morphological assessment, we used a panel of immunohistochemical stainings including: hepatocellular cytokeratin, CK7, CK19, Ki67, PCNA, chromogranin A, synaptophysin, NSE, insulin, calcitonin, parathormon, CD34, EBV (LMP), Bcl2, cyclin D1.
  
  
  RESULTS
  In 3 out of 4 cases, we observed co-expression of CK7 with hepatocellular CK. In addition, there was positive staining with some endocrine markers in the majority of patients. In one case, we found strong cyclin D1 immunoreactivity which correlated with EBV (LMP) immunoreactivity, in the same patient. The score of PCNA positivity varied between 15 and 90%. In all cases Ki67 was negative.
  
  
  CONCLUSIONS
  The incidence of FLC, among all hepatocellular carcinomas diagnosed in our Department was 5.1%. In accordance with other reports, all our FLC cases were young patients without underlying liver disease. We were unable to find a correlation between FLC cellular immunophenotype, and histological and clinical markers of malignancy. In addition, it appears that PCNA is a better marker of cell-proliferation in FLC than Ki67. The significance of EBV infection in FLC requires further study.
authors.affiliation: Department of Pathology, Medical University of Warsaw, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Górnicka
authors.forename: Bogna
authors.initials: B
authors.lastname: Ziarkiewicz-Wróblewska
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Wróblewski
authors.forename: Grzegorz Marek
authors.initials: GM
authors.lastname: Wilczynski
authors.forename: Lukasz
authors.initials: L
authors.lastname: Koperski
authors.forename: Marek
authors.initials: M
authors.lastname: Krawczyk
authors.forename: Aleksander
authors.initials: A
authors.lastname: Wasiutynski
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology*; D002455:Cell Division; D019938:Cyclin D1 / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D053552:Keratin-7; D007633:Keratins / Q000378:metabolism; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology*; D008875:Middle Aged; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013194:Staining and Labeling; D014763:Viral Matrix Proteins / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; C037662:EBV-associated membrane antigen, Epstein-Barr virus; C507497:KRT7 protein, human; D053552:Keratin-7; D018809:Proliferating Cell Nuclear Antigen; D014763:Viral Matrix Proteins; D019938:Cyclin D1; D007633:Keratins