title: Expression of CK7, Cam 5.2 and Ber-Ep4 in cutaneous squamous cell carcinoma.
abstract: BACKGROUND
  Cytokeratin 7 (CK7) and Cam 5.2 are often used to differentiate extramammary Paget's disease (EPD) from squamous cell carcinoma (SCC) in situ because they are generally considered to be expressed in the former but not in the latter. However, we have encountered CK7+ and Cam 5.2+ SCCs.
  
  
  METHODS
  We evaluated CK7, Cam 5.2 and Ber-Ep4 expression in SCC and EPD.
  
  
  RESULTS
  We found significant CK7 and Cam 5.2 positivity in SCCs, particularly in those with a pagetoid pattern. Only one case expressed Ber-Ep4.
  
  
  CONCLUSIONS
  We conclude that CK7 and Cam 5.2 expression may occur in SCC. A panel including Ber-Ep4 is advisable for immunohistochemical differentiation of EPD from SCC.
authors.affiliation: Department of Pathology, The Penn State Hershey Medical Center, Hershey, PA 17033, USA. lclarke@hmc.psu.edu
authors.forename: Loren E
authors.initials: LE
authors.lastname: Clarke
authors.forename: Andrea B
authors.initials: AB
authors.lastname: Conway
authors.forename: Nicole M
authors.initials: NM
authors.lastname: Warner
authors.forename: Patricia N
authors.initials: PN
authors.lastname: Barnwell
authors.forename: Jennifer
authors.initials: J
authors.lastname: Sceppa
authors.forename: Klaus F
authors.initials: KF
authors.lastname: Helm
mesh_terms: D015415:Biomarkers; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D053552:Keratin-7 / Q000096:biosynthesis*; D007633:Keratins / Q000096:biosynthesis*; D008297:Male; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D012878:Skin Neoplasms / Q000378:metabolism / Q000473:pathology; D000951:Antigens, Neoplasm
chemical_list: D015415:Biomarkers; D014408:Biomarkers, Tumor; D053552:Keratin-7; D007633:Keratins; D009363:Neoplasm Proteins; C400901:CAM 5.2 antigen; C115012:human epithelial antigen-125; D000951:Antigens, Neoplasm