Tag Archives: WT-1

WT-1 (Wilms tumor gene product)

WT-1 (Wilms tumor gene product) is a marker most commonly used to identify OVARIAN SEROUS CARCINOMAS.  It is also commonly used in a panel to differentiate mesothelioma (positive) from adenocarcinoma (negative).  WT-1 has a normal expression distribution in adult tissues, which includes Sertoli cells, ovarian stromal and surface epithelium, and mesothelium.  The 6F-H2 clone has shown better sensitivity compared to other WT-1 antibodies (Ordonez).
 
Tumors / lesions expressing WT-1:
  • Mesothelioma (>75% of epithelial mesotheliomas, usually negative in sarcomatoid variants)
  • Ovarian Serous Carcinomas
  • Wilms tumor
  • Desmoplastic Small Round Cell Tumors
  • Metanephric Adenomas
 
Tumor
Expression (%)
Ovarian Serous Carcinoma
93%
Ovarian Mucinous Carcinoma
0%
Pancreatobiliary Carcinoma
0%
Breast Carcinoma
0%
Lung Carcinoma
0%
Colon Adenocarcinoma
0%
Renal Cell Carcinoma
0%
Thyroid Carcinoma
0%
Prostate Adenocarcinoma
0%
 
WT-1 expression in differentiating mesothelioma from adenocarcinoma (Marchevsky).
Tumor
Expression (%)
Epithelioid Mesothelioma
77%
Sarcomatoid Mesothelioma
13%
Adenocarcnioma
4%
Photomicrographs
WT-1 - Wilms Tumor
WT-1 – Wilms Tumor
WT-1 - Mesothelioma
WT-1 – Mesothelioma
WT-1 - Ovarian Serous Carcinoma
WT-1 – Ovarian Serous Carcinoma
WT-1 - Stromal Cells
WT-1 expression in stromal cells.

 
References:
Muir, T. E., Cheville, J. C., & Lager, D. J. (2001). Metanephric adenoma, nephrogenic rests, and Wilms’ tumor: a histologic and immunophenotypic comparison. The American Journal of Surgical Pathology, 25(10), 1290–1296.
 
Marchevsky, A. M. (2008). Application of immunohistochemistry to the diagnosis of malignant mesothelioma. Archives of Pathology & Laboratory Medicine, 132(3), 397–401.
 
Ordóñez, N. G. (2005). Immunohistochemical diagnosis of epithelioid mesothelioma: an update. Archives of Pathology & Laboratory Medicine, 129(11), 1407–1414.  
  
Hadi, AIMM Annual Meeting, “Carcinomas of Unknown Primary”, presentation, 2011.