Immunohistochemistry staining of the tumor cells revealed diffuse positivity for p63, zonal positivity for epithelial membrane antigen (EMA) and the low molecular-weight cytokeratin CK7
. Carcinoembryonic antigen (CEA) was present in rare tumor cells and the B-cell lymphoma-2 marker (Bcl-2) was positive in some of the tumor cells.
In our study of 60 cases, 24 (40%) cases of squamous cell carcinoma being the most common with P63 positivity, 20 (33%) cases of adenocarcinoma with TTF-1, CK 7, EGFR and Napsin A positivity with negative P63 and 15 (25%) cases of small cell lung carcinoma with TTF-1 positivity and Napsin A negativity and 1 (1.66%) case of metastasis from colon adenocarcinoma with CK7
negativity and CK20 positivity were confirmed and out of 60 cases, 39 (65%) were males and 21 (35%) were females.
We also found positive staining for CK7
but negative for TTF-1.
In the paraffin-embedded (permanent) sections of the mass, the slit-like spaces were thought to be the glandular parts of an adenomatoid tumor or vascular structures and they stained negative for calretinin and CK7
and positive for CD34.
The tumor cells were strongly positive for cytokeratin 7 (CK7
), cytokeratin 5/6 (CK5/6), tumor protein 63 (p63), estrogen receptor (ER), progesterone receptor (PR) and were negative for cytokeratin 20 (CK20Figure 3).
was applied and showed positive expression in all the cases.
The tumor cells were immunoreactive for CK7
, CK19, CEA, and EMA but were nonimmunoreactive for CK20 and CDX2.
(10) Vimentin has been found to stain 87% of clear cell carcinoma and CD10 has been found to stain 94% to 100%, whereas CK7
is negative in 63% to 100% of cases.
The samples were stained with hematoxylin and eosin and the diagnosis was confirmed by immunochemistry using TTF-1, CK7
and napsin A panel of antibodies for adenocarcinoma confirmation and p63 and CK5/6 antibodies to exclude squamous cell carcinoma.
Immunohistochemical expression of CDX2 in primary ovarian mucinous tumors and metastatic mucinous carcinomas involving the ovary: comparison with CK20 and correlation with coordinate expression of CK7
. Mod Pathol 2006; 19: 1421-1428.
Immunohistochemical studies were carried out on the cell block sections using antibodies to CK AE1/AE3, CK5/6, Cam 5.2, CK7
, S100, Melan A, HMB45, EMA, vimentin, CEA and Alpha 1AT.
Immunostaining results showed calretinin (−), CK7
(+), and paired-box gene 8 (PAX-8) (+) [Figure 1]b,[Figure 1]c,[Figure 1]d.