title: Expression of CDX2, cytokeratins 7 and 20 in sinonasal intestinal-type adenocarcinoma.
abstract: CDX2 is a transcription factor expressed by intestinal epithelium. It is considered as a sensitive marker for a colorectal or-less frequently-gastric origin of adenocarcinomas. The pattern of coordinated expression of cytokeratin (CK) 7 and CK20 is also useful for the diagnosis of the origin of metastatic adenocarcinomas. Expression of CDX2, CK7 and CK20 was investigated in 14 cases of sinonasal intestinal-type adenocarcinoma (SIA), a particular tumor with an enteric-cell-type appearance. Formalin-fixed, paraffin embedded tissue sections were immunostained with monoclonal antibodies using the biotin-labeled streptavidin technique. All of the cases expressed CDX2, being stained 50 to 100% of the tumor cells (mean: 87.2%). CK7 positivity was detected in 8 cases (57.1%), with the staining of 10 to 100% of cells (mean: 65.6%), and CK20 was found in all the tumors (10 to 100% of cells; mean: 78.8%). The histologic resemblance between SIA and colorectal adenocarcinoma is reinforced by the expression of CDX2 and CK20, which are virtually constant in both neoplasms. CDX2 seems to be a marker for cellular phenotype better than an indicator of the origin of adenocarcinomas. CK7 is expressed in SIA less frequently than in colonic adenocarcinoma, but with a rate similar to the subset of rectal tumors, making the differential diagnosis between the two neoplasms difficult.
authors.affiliation: Department of Pathology, Centro Médico POVISA, Vigo, Pontevedra, Spain. jaortiz@povisa.es
authors.forename: José A
authors.initials: JA
authors.lastname: Ortiz-Rey
authors.forename: Carlos
authors.initials: C
authors.lastname: Alvarez
authors.forename: Pilar
authors.initials: P
authors.lastname: San Miguel
authors.forename: Begoña
authors.initials: B
authors.lastname: Iglesias
authors.forename: Iosu
authors.initials: I
authors.lastname: Antón
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000503:physiopathology; D000368:Aged; D000369:Aged, 80 and over; D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000096:biosynthesis / Q000235:genetics*; D007414:Intestinal Neoplasms / Q000378:metabolism* / Q000503:physiopathology; D053554:Keratin-20; D053552:Keratin-7; D007633:Keratins / Q000096:biosynthesis / Q000235:genetics*; D008875:Middle Aged
chemical_list: D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins; D007381:Intermediate Filament Proteins; C507499:KRT20 protein, human; C507497:KRT7 protein, human; D053554:Keratin-20; D053552:Keratin-7; D007633:Keratins