Primary carcinoid tumor of the common hepatic duct: A rare case with immunohistochemical and molecular findings.
We report immunohistochemical (IHC) and molecular findings in a rare case of a carcinoid tumor of the extrahepatic bile ducts in a 33-year-old woman, who presented with a 3.9x2.8x2.6 cm mass within the right and common hepatic ducts. She underwent surgery and a carcinoid tumor was identified. This lesion is of interest because in addition to the morphological and cytological features of a typical carcinoid, it demonstrated a distinct pleomorphic area immunoreactive for gastrin. By molecular analysis, loss of heterozygosity (LOH) with opposite allelic patterns between the gastrin-positive and gastrin-negative areas of the tumor was identified. The molecular studies for LOH along with the morphology and IHC profiling suggest that this second population of gastrin-positive carcinoid cells may represent a new clone within the carcinoid tumor with differentiation toward gastrin production or may represent the next step in the carcinogenic process with a gradual emergence of a more aggressive clone.
Ligato
Saverio
S
Department of Pathology and Laboratory Medicine, Hartford Hospital, Hartford, CT, USA.
Furmaga
Wieslaw
W
Cartun
Richard W
RW
Hull
David
D
Tsongalis
Gregory J
GJ
D000328:Adult; D000483:Alleles; D001650:Bile Duct Neoplasms / Q000235:genetics* / Q000276:immunology*; D002276:Carcinoid Tumor / Q000235:genetics* / Q000276:immunology*; D002471:Cell Transformation, Neoplastic; D005260:Female; D006500:Hepatic Duct, Common / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D019656:Loss of Heterozygosity