CDX-2 expression in pulmonary fine-needle aspiration specimens: a useful adjunct for the diagnosis of metastatic colorectal adenocarcinoma.

Abstract

CDX-2 is a homeobox gene, which encodes a transcription factor that plays a vital role in the development and differentiation of intestinal epithelial cells. Recent studies showed that CDX-2 protein expression by immunohistochemistry (IHC) has a high predictive value for confirming the diagnosis of colorectal adenocarcinoma (ACA). The differentiation of primary pulmonary ACA from metastatic colorectal ACA can be extremely challenging on fine-needle aspiration (FNA). The results of immunostains for TTF-1, CK 7, and CK 20 may be controversial in the differential diagnosis. In this study, we evaluated the clinical utility of CDX-2 in lung FNA specimens. Cell blocks from 41 primary lung and 20 colorectal ACAs metastatic to the lungs were retrieved. Cell block sections were immunostained with a CDX-2 monoclonal antibody. Sensitivity and specificity of CDX-2 for colorectal ACA was 75 and 100%, respectively. All five cases negative for CDX-2 were moderately to poorly differentiated colorectal ACAs. Our study confirms that CDX-2 is a highly useful immunohistochemical marker for the differentiation of primary pulmonary ACA from colorectal ACA metastatic to the lungs in FNA specimens. Of diagnostic importance is the loss of CDX-2 immunoreactivity in poorly differentiated colorectal ACAs.

• Authors: Pascale Hummel Levine, Alla Joutovsky, Joan Cangiarella, Herman Yee, Aylin Simsir
• Journal: Diagnostic cytopathology (Diagn Cytopathol) Vol. 34 Issue 3 Pg. 191-5 (Mar 2006) ISSN: 8755-1039 [Print] United States
• PMID: 16470859 (Publication Type: Journal Article, Validation Study)
• Copyright: 2006 Wiley-Liss, Inc.

Chemical References

• CDX2 Transcription Factor
• DNA, Neoplasm
• Homeodomain Proteins
• Trans-Activators

Topics

• Adenocarcinoma (chemistry, diagnosis, pathology, secondary)
• Biopsy, Fine-Needle (methods)
• CDX2 Transcription Factor
• Colorectal Neoplasms (chemistry, diagnosis, pathology)
• DNA, Neoplasm (analysis)
• Diagnosis, Differential
• Gene Expression Regulation, Neoplastic
• Genes, Homeobox
• Homeodomain Proteins (analysis, genetics)
• Humans
• Immunohistochemistry
• Lung Neoplasms (chemistry, diagnosis, pathology, secondary)
• Predictive Value of Tests
• Reproducibility of Results
• Trans-Activators (analysis, genetics)