title: Immunophenotypic and prognostic analysis of PAX8 and TTF-1 expressions in neuroendocrine carcinomas of thymic origin: A comparative study with their pulmonary counterparts.
abstract: OBJECTIVE
  To investigate the immunoreactivity of TTF-1 and PAX8 in neuroendocrine carcinoma of thymic (TNEC) and pulmonary origins (PNEC), and whether their immunophenotyping could be used to distinguish between NEC of the two sites, as well as prognosis of patients with TNEC.
  
  
  METHODS
  Twenty-two cases of TNEC and 20 cases of PNEC were selected for immunohistochemical analysis using PAX8 and TTF-1. Clinical data and follow-up information were obtained for survival analyses.
  
  
  RESULTS
  TTF-1 immunoreactivity was seen in 19 PNEC cases (95%) and 13 TNEC cases (59.1%). PAX8 was negative in all pulmonary tumors while positive in 19 thymic cases (86.4%). TTF-1 positivity was associated with high sensitivity but low specificity for PNEC, and adding PAX8 negativity significantly increased the specificity. PAX8 positivity alone showed essentially 100% specificity and 86.4% sensitivity for TNEC. Survival analysis showed lung metastasis as a significant prognostic factor in TNEC.
  
  
  CONCLUSIONS
  Our study demonstrated that TTF-1/PAX8 immunophenotyping may be helpful for differential diagnosis of NECs of pulmonary and thymic origins. TTF-1+/PAX8- immunophenotyping showed high specificity for PNECs, while PAX8+ alone showed a good diagnostic accuracy for TNEC. Lung metastasis was a predictive factor that associated with survival of TNEC patients. J. Surg. Oncol. 2016;114:697-702. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Yalan
authors.initials: Y
authors.lastname: Bi
authors.affiliation: Department of Pathology, Jiangxi Maternal and Child Health Hospital, Nanchang, China.
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Department of General Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Shanqing
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of General Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of General Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Yeye
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of General Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Dongjie
authors.initials: D
authors.lastname: Ma
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Mao
authors.affiliation: Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Yuzhou
authors.initials: Y
authors.lastname: Guan
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. jiechen693@163.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. yunxiaomeng19@163.com.
authors.forename: Yunxiao
authors.initials: Y
authors.lastname: Meng
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018278:Carcinoma, Neuroendocrine / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D008297:Male; D008875:Middle Aged; D000072636:PAX8 Transcription Factor / Q000378:metabolism*; D010641:Phenotype; D011379:Prognosis; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016019:Survival Analysis; D013953:Thymus Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D014157:Transcription Factors
chemical_list: D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D000072636:PAX8 Transcription Factor; C083325:PAX8 protein, human; C504003:TTF1 protein, human; D014157:Transcription Factors
keywords: differential diagnosis; paired box gene 8 (PAX8); pulmonary neuroendocrine carcinoma (PNEC); thymic neuroendocrine carcinoma (TNEC); thyroid transcription factor-1 (TTF-1)