title: Potential diagnostic utility of CDX-2 immunophenotyping in extramammary Paget's disease.
abstract: Extramammary Paget's disease (EMPD) is a rare condition whose importance is amplified by its association with either cutaneous or internal malignancy. Recently it has been shown that EMPD is not a single disease but can be divided into cutaneous and endodermal subtypes. The authors studied 12 new cases of immunohistochemically well-characterized EMPD, including HER-2/neu and CDX-2 immunophenotyping. The latter represents a novel application of this nuclear transcription factor, considered to be a relatively specific IHC marker for gastrointestinal-type epithelium. Cutaneous EMPD, accounting for 10 of the 12 (83%) cases, was CDX2-/HER2+; endodermal EMPD, accounting for 2 of the 12 (17%) cases, was CDX2+/HER2-. Four of the 12 cases (33%) were associated with a malignancy (two cutaneous adenocarcinomas, two colorectal carcinomas). The two cases of cutaneous adenocarcinoma occurred in the cutaneous group (2/10 [20%]), while the two cases of rectal carcinoma (one invasive, one in situ) occurred in the endodermal group (2/2 [100%]). Since EMPD subtypes have specific implications with regard to cancer risk, immunophenotyping should be performed in all cases. CDX-2 immunoreactivity may be useful in the subtyping of EMPD.
authors.affiliation: Department of Pathology and Laboratory Medicine, Hartford Hospital, CT 06102, USA.
authors.forename: Hao Audrey
authors.initials: HA
authors.lastname: Zeng
authors.forename: Richard
authors.initials: R
authors.lastname: Cartun
authors.forename: Andrew
authors.initials: A
authors.lastname: Ricci
mesh_terms: D000071616:CDX2 Transcription Factor; D005260:Female; D018398:Homeodomain Proteins / Q000032:analysis*; D006801:Humans; D016130:Immunophenotyping; D008297:Male; D010145:Paget Disease, Extramammary / Q000145:classification* / Q000175:diagnosis* / Q000276:immunology; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D012189:Retrospective Studies; D015534:Trans-Activators / Q000032:analysis*
chemical_list: D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D015534:Trans-Activators