title: Thyroid Transcription Factor-1 Expression in Adenocarcinomas of the Bile Duct.
abstract: BACKGROUND
  The immunoreactivity of thyroid transcription factor-1 (TTF-1) is a very specific marker for lung and thyroid neoplasms; the expression of TTF-1 has also been demonstrated in extrapulmonary carcinomas. We examined the expression of TTF-1 in 15 intestinal-type adenocarcinomas of the extrahepatic bile duct. We then compared the expression to TTF-1 staining with other immunohistochemical markers including cytokeratin (CK) 7, CK20, caudal-type homeobox transcription factor 2 (CDX2), Napsin A, and MUC2. We additionally compared the clinicopathological prognostic factors with the TTF-1 expression status.
  
  
  RESULTS
  Nuclear TTF-1 staining was detected in 2 cases (13.3%), and Napsin A was positive in the same 2 cases (13.3%). All cases were positive for CK20, CDX2, and MUC2; 5 cases were positive for CK7. There was no correlation between TTF-1 expression and the clinicopathological characteristics.
  
  
  CONCLUSIONS
  To avoid potential pitfalls, TTF-1 should be interpreted in conjunction with the clinical setting, histology, and the results of markers such as CK7, CK20, Napsin A, and CDX2. This report is the first of TTF-1 positivity in adenocarcinomas from the extrahepatic biliary tract.
authors: Instituto Nacional de Cancerología, Mexico City, Mexico saul.lino.sil@gmail.com.
authors: Leonardo S
authors: LS
authors: Lino-Silva
authors: Instituto Nacional de Cancerología, Mexico City, Mexico.
authors: Rosa A
authors: RA
authors: Salcedo-Hernández
authors: Instituto Nacional de Cancerología, Mexico City, Mexico.
authors: Miguel A
authors: MA
authors: García-Gómez
authors: Instituto Nacional de Cancerología, Mexico City, Mexico.
authors: Erika B
authors: EB
authors: Ruiz-García
authors: Universidad Nacional Autónoma de México, Mexico City, Mexico.
authors: José M
authors: JM
authors: Aguilar-Romero
authors: Universidad Nacional Autónoma de México, Mexico City, Mexico.
authors: Jorge A
authors: JA
authors: Domínguez-Rodríguez
authors: Instituto Nacional de Cancerología, Mexico City, Mexico.
authors: Ángel
authors: Á
authors: Herrera-Gómez
authors: Instituto Nacional de Cancerología, Mexico City, Mexico.
authors: Héctor A
authors: HA
authors: Maldonado-Martínez
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000368:Aged; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism; D001650:Bile Duct Neoplasms / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism; D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins / Q000378:metabolism; D006801:Humans; D053554:Keratin-20 / Q000378:metabolism; D053552:Keratin-7 / Q000378:metabolism; D008297:Male; D055262:Mucin-2 / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins; C507499:KRT20 protein, human; D053554:Keratin-20; D053552:Keratin-7; C524625:MUC2 protein, human; D055262:Mucin-2; C000614412:NKX2-1 protein, human; D009687:Nuclear Proteins; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors; D016282:Aspartic Acid Endopeptidases; C498549:NAPSA protein, human
keywords: Biliary tract; TTF-1; cancer; choledocho; immunohistochemistry