CDX2 Expression in Columnar Cell Variant of Papillary Thyroid Carcinoma

This is the authors' abstract. We don't add key points for this paper.

The columnar cell variant of papillary thyroid carcinoma (CCV-PTC) is a rare subtype of PTC that exhibits morphologic features often described as reminiscent of secretory endometrium or colonic adenomas/adenocarcinomas. CDX2, a nuclear transcription factor, is important for intestinal development. It is normally expressed in intestinal epithelium and is also detected in adenoma and adenocarcinomas of the gastrointestinal tract; however, it has also been reported in tumors of other sites with intestinal-type morphologic features. We evaluated CDX2 expression in CCV-PTC and in a thyroid tissue microarray composed of various benign and malignant thyroid lesions. CDX2 expression was identified in 6 (55%) of 11 cases of CCV-PTC, but not in any other benign and malignant thyroid lesions. We conclude that CDX2 is selectively expressed in CCV-PTC and can be used in distinguishing it from other variants of PTC with overlapping morphologic features.