title: PAX-5 expression in pulmonary neuroendocrine neoplasms: its usefulness in surgical and fine-needle aspiration biopsy specimens.
abstract: The World Health Organization classification of lung tumors recognizes 4 histologic subtypes of pulmonary neuroendocrine carcinomas (NECs), which include typical carcinoids (TCs), atypical carcinoids (ACs), small cell carcinomas (SCCs), and large cell NECs (LCNECs). These tumors can be misclassified owing to morphologic parallels, indicating the necessity for adjunctive tests for correct classification. We evaluated immunohistochemical expression of PAX-5 in histologic and fine-needle aspiration (FNA) specimens of pulmonary NECs. Staining was stratified by intensity (0 to 3+) and percentage of cells stained as focal (<10%) or diffuse (=10%). PAX-5 expression was present in 29/37 (78%) of high-grade NECs (22/26 SCCs, 1/2 LCNECs, and 6/9 combined tumors) and none of 51 TCs and ACs; FNA specimens showed concordant staining. This study confirmed that PAX-5 is a useful marker in FNA and surgical specimens for the discrimination of low- to intermediate-grade NECs from high-grade NECs with 100% specificity and 79% sensitivity in surgical specimens.
authors.affiliation: Department of Pathology, Weill Cornell Medical Center, New York, NY, USA.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Sica
authors.forename: Madeline F
authors.initials: MF
authors.lastname: Vazquez
authors.forename: Nassar
authors.initials: N
authors.lastname: Altorki
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Port
authors.forename: Paul C
authors.initials: PC
authors.lastname: Lee
authors.forename: Yifang
authors.initials: Y
authors.lastname: Liu
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hyjek
authors.forename: Anjali
authors.initials: A
authors.lastname: Saqi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D044963:Biopsy, Fine-Needle; D002276:Carcinoid Tumor / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D018287:Carcinoma, Large Cell / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D018278:Carcinoma, Neuroendocrine / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D018288:Carcinoma, Small Cell / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D002452:Cell Count; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D051757:PAX5 Transcription Factor / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D051757:PAX5 Transcription Factor; C497281:PAX5 protein, human