title: Fine needle aspiration biopsy of hepatocellular carcinoma resembling neuroendocrine tumor. A case report.
abstract: BACKGROUND
  The incidence of hepatocellular carcinoma (HCC) is steadily increasing in western countries. Its present incidence in Italy is about 6.9/100,000. The diagnosis is usually made by a combination of ultrasound (US), computed tomography (CT) and fine needle aspiration biopsy (FNAB). HCC resembling a neuroendocrine tumor has been described, but no previous FNAB diagnosis was reported.
  
  
  METHODS
  An asymptomatic 45-year-old man underwent a CT scan after incidental US detection of multiple focal lesions in both lobes of the liver. FNAB showed clusters of small neoplastic cells with hyperchromatic nuclei and scanty cytoplasm. A thin tissue core showed a microacinar pattern very similar to that of a neuroendocrine tumor. A large panel of specific antibodies displayed an immunophenotype consistent with HCC.
  
  
  CONCLUSIONS
  In this rare variant of HCC, the final diagnosis could be assessed only by correlating the cytologic, microhistologic and immunohistochemical features.
authors.affiliation: Department of Pathology, St. Anna Hospital, Como, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Piatti
authors.forename: B
authors.initials: B
authors.lastname: Caspani
authors.forename: C
authors.initials: C
authors.lastname: Giudici
authors.forename: D
authors.initials: D
authors.lastname: Ferrario
mesh_terms: D000328:Adult; D000918:Antibody Specificity; D001707:Biopsy, Needle; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000276:immunology / Q000473:pathology*; D003937:Diagnosis, Differential; D006801:Humans; D007124:Immunoenzyme Techniques; D016130:Immunophenotyping; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000276:immunology / Q000473:pathology*; D008297:Male; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000276:immunology / Q000473:pathology; D014057:Tomography, X-Ray Computed