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.
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.
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.
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.
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.
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%).
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).
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.
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.
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.
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.