Staining of desmosomal plaque-related proteins may be useful in the diagnosis of lung SCC.<b>Materials and methods:</b> We compared the usefulness of six conventional (CK5/6, p40, p63, CK7, TTF1, and Napsin A) and three novel (PKP1, KRT15, and DSG3) markers to distinguish between lung SCC and AC in 85 small biopsy specimens (41 ACs and 44 SCCs).
TTF-1 and napsin A IHC stainings had similar specificity but better sensitivity for adenocarcinoma than the mucin stains, but addition of PASD or ABPAS identified more tumors as adenocarcinomas (n = 8 and n = 10, respectively) than napsin A (n = 1) in cases with solid growth that were negative for TTF-1 and p40.
As there are few data from South Africa, we aimed to determine utility of TTF-1, napsin A, p63 and CK5 immunostaining on fine needle aspiration (FNA) cell block and formalin-fixed paraffin-embedded tissue biopsy specimens in subtyping NSCLC as adenocarcinoma and squamous cell carcinomas.
In conclusion, LCNECs are unique among lung neuroendocrine neoplasms in that some of these tumors exhibit low-level expression of exocrine marker napsin A, and harbor genomic alterations typical of adenocarcinoma.
Among our patients (48 men and 2 women) all adenocarcinoma (confirmed by histology and IHC with TTF1/Napsin A), 94% were smokers exceeding the tobacco risk threshold (at least 25 pack-years) and the women were none.
Immunohistochemically, the adenocarcinomas were positive for MUC6 (4/5), PAX8 (3/5), CK7 (5/5), CK20 (1/5), CDX2 (5/5), CA19.9 (5/5), CEA (4/5), CA125 (5/5), and hepatocyte nuclear factor 1β (5/5). p16, estrogen receptor, and Napsin A were negative in all cases tested, whereas p53 exhibited mutation-type staining in 3/5 cases.
Unlike the common adenocarcinomas of the lung, WDFAs showed nuclear/cytoplasmic expression of β-catenin, diffuse expression for TTF-1, and focal for Napsin A.
The aim of this study was to compare the performance of TTF-1 and Napsin-A in determining the primary origin of adenocarcinoma in malignant serous effusion.
LC patients were additionally subdivided into three immunohistochemistry groups based on positive expression of TTF-1/Napsin A (adenocarcinoma-like, n = 24; 59%), CK5/P40 (squamous-like, n = 5; 12%), or no marker expression (marker-negative, n = 12; 29%).
Transcript levels of 10 genes (SFTPB, SFTPC, SFTPD, SLC34A2, LAMP3, CACNA2D2, AGER, EMP2, NKX2-1, and NAPSA) were significantly associated with survival in the adenocarcinoma subgroup, thus qualifying as promising biomarker candidates.
In the case we report, the pulmonary-type adenocarcinoma was closely associated with a bronchial structure and exhibited diffuse positive immunohistochemical staining with TTF1, PE10, and napsin A. Molecular studies revealed no evidence of epidermal growth factor receptor mutation, a molecular alteration which may be found in primary pulmonary adenocarcinoma.