Napsin A expression in primary mucin-producing adenocarcinomas of the lung: an immunohistochemical study.
Immunohistochemical expression of napsin A in primary pulmonary mucinous tumors is not well established. Napsin A immunoreactivity was evaluated in 43 mucin-producing adenocarcinomas of the lung consisting of 18 tumors formerly classified as mucinous bronchioloalveolar carcinoma, 15 colloid adenocarcinomas, 5 solid predominant adenocarcinomas with mucin production, and 5 adenocarcinomas with signet ring cell features, as well as in 25 extrapulmonary mucinous adenocarcinomas of different anatomic sites. Immunohistochemical expression of thyroid transcription factor 1 (TTF-1) was also compared. Thirty-three percent of mucinous lung tumors exhibited positive immunoreactivity for napsin A, whereas 42% expressed TTF-1. All 25 extrapulmonary mucinous adenocarcinomas lacked expression of napsin A and TTF-1. Mucin-producing neoplasms of the lung infrequently express napsin A, suggesting that immunohistochemical assessment of napsin A may have limited diagnostic usefulness for distinguishing primary and metastatic mucinous adenocarcinomas involving the lung.
Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA.
Jeffrey
J
Wu
Peiguo G
PG
Chu
Zhong
Z
Jiang
Sean K
SK
Lau
D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D014157:Transcription Factors
D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; C504003:TTF1 protein, human; D014157:Transcription Factors; D016282:Aspartic Acid Endopeptidases; C498549:NAPSA protein, human