Expression of Napsin A in Carcinomas from Various Organs.
Kai Zhang, Haiyan Liu, Shaobo Zhu, Myra Wilkerson, Fan Lin. Geisinger Medical Center, Danville, PA
Background: Napsin A has been recently reported as a highly sensitive and specific marker for identifying a primary adenocarcinoma of the lung. Its expression has also been demonstrated in papillary and clear cell renal cell carcinomas. In this study, we investigate the expression of napsin A in carcinomas from various organs using a single immunostaining system (Ventana XT).
Design: We immunohistochemically evaluated the expression of napsin A (Cat No. 760-4446; rabbit polyclonal; prediluted; Ventana) on 862 cases of carcinoma from various organs on tissue microarray sections. The staining intensity was graded as weak or strong. The distribution was recorded as negative (<5% of tumor cells stained), 1+ (5-25%), 2+ (26-50%), 3+ (51-75%), or 4+ (>75%).
Results: The immunostaining results are summarized in Table 1. Weak nuclear staining was also observed in 6 of 15 seminomas and 3 of 8 embryonal carcinomas in addition to cytoplasmic granular staining.
|Tumor||Positive cases % (N)|
|Adenocarcinoma, lung||93% (50/54)|
|Squamous cell carcinoma, lung||5% (2/42)|
|Papillary renal cell carcinoma||69% (18/26)|
|Clear cell renal cell carcinoma||38% (20/53)|
|Adenocarcinoma, colon||29% (11/38)|
|Embryonal carcinoma||33% (8/24)|
|Yolk Sac tumor||50% (6/12)|
|Papillary carcinoma, thyroid||18% (8/45)|
|Adenocarcinoma, esophagus||17% (5/30)|
|Adenocarcinoma, stomach||6% (1/18)|
|Adenocarcinoma, pancreas||5% (3/56)|
|Urothelial carcinoma, bladder||5% (2/40)|
|Adenocarcinoma, prostate||0 (0/100)|
|Hepatocellular carcinoma||0 (0/18)|
|Ductal carcinoma, breast||0 (0/110)|
|Lobular carcinoma, breast||0 (0/53)|
|Follicular carcinoma, thyroid||0 (0/36)|
|Medullary carcinoma, thyroid||0 (0/10)|
|Papillary serous carcinoma, ovary||0 (0/15)|
|Adrenal cortical neoplasm||0 (0/24)|