title: Thyroid transcription factor 1 and napsin a double staining in lung adenocarcinoma in pleural fluid.
abstract: OBJECTIVE
  Thyroid transcription factor 1 (TTF-1)/napsin A double staining is useful for the identification of primary lung adenocarcinoma. We examined its performance in pleural fluid.
  
  
  METHODS
  Thirty-eight pleural-fluid specimens with lung adenocarcinoma were identified. Among these, 23 cases were diagnosed with a lung primary adenocarcinoma and 15 with a nonlung primary adenocarcinoma [breast (n = 13), ovarian (n = 1) and esophageal (n = 1)]. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded cell blocks. Expression of TTF-1 as a brown nuclear stain and napsin A as a red cytoplasmic stain were identified as positive staining.
  
  
  RESULTS
  In lung adenocarcinoma, 19 out of the 23 (83%) cases were positive for the TTF-1/napsin A double stain, 1 (4%) was positive for TTF-1 only, 2 (9%) were positive for napsin A only and 1 (4%) was negative for the TTF-1/napsin A double stain. All 15 cases of nonlung primary adenocarcinoma were negative for the TTF-1/napsin A double stain.
  
  
  CONCLUSIONS
  The sensitivity of napsin A for diagnosing lung adenocarcinoma is slightly higher than that of TTF-1.
authors: Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA.
authors: Lian
authors: L
authors: Liu
authors: Cynthia
authors: C
authors: Cohen
authors: Momin T
authors: MT
authors: Siddiqui
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry / Q000175:diagnosis* / Q000378:metabolism; D016282:Aspartic Acid Endopeptidases / Q000032:analysis* / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000378:metabolism; D009687:Nuclear Proteins / Q000032:analysis* / Q000378:metabolism; D016066:Pleural Effusion, Malignant / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D012680:Sensitivity and Specificity; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors / Q000032:analysis* / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; C000614412:NKX2-1 protein, human; D009687:Nuclear Proteins; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors; D016282:Aspartic Acid Endopeptidases; C498549:NAPSA protein, human