Diagnostic value of TTF-1,Napsin A,CK7,P63 and CK5/6 immunostaining on pulmonary biopsy specimens in histopathologic classification of lung cancer

Objective To detect the expression of thyroid transcription factor 1(TTF-1),Napsin A,CK7,P63 and CK5/6on pulmonary biopsy specimens,and study their valuation in the diagnosis of various histologic typing lung carcinoma,to find the most cost-effective panel.MethodsOf 209 specimens from fine-needle aspiration or transbronchial biopsy,202 were primary lung carcinomas including 162non-small cell carinomas(NSCLCs),40 small cell lung cancers(SCLCs),and 7metastatic carcinomas.Of 162non-small cell carinomas(NSCLCs),adenocarcinoma(AC)were 102,squamous cell carcinoma(SCC)were 55 and large cell carcinoma(LCC)were 5.Expression of TTF-1,Napsin A,CK7,P63 and CK5/6was detected by immunohistochemistry staining.The expression of level marker was judged as positive:≥10%,negative:10%.ResultsThe positive nuclear immunoreactivity of TTF-1 was identified in 39 of 40SCLCs(97.5%),it was the most highest in SCLC.But in squamous cell carcinomas(SCCs)was 3.6%(2/55).TTF-1and Napsin A had 96%and 100%specificity for adenocarcinoma(AC),but CK7 had 100%sensitivity.P63 had 96% specificity for squamous cell carcinoma(SCC),but CK5/6had 95% sensitivity.Conclusion To distinguish of poorly differentiated adenocarcinoma and squamous cell carcinoma,poorly differentiated squamous cell carcinoma and small cell carcinoma on limited fine-needle aspiration or transbronchial biopsy specimens,assisting immunohistochemical staining,combination of TTF-1,Napsin A,P63 and CK5/6is the most cost-effective panel and contribute to differentiate primary lung adenocarcinoma and metastatic carcinoma.