title: Comparative analysis of cytokeratin 15, TDAG51, cytokeratin 20 and androgen receptor in sclerosing adnexal neoplasms and variants of basal cell carcinoma.
abstract: BACKGROUND
  Desmoplastic trichoepithelioma (DTE), morpheaform basal cell carcinoma (BCC) and microcystic adnexal carcinoma (MAC) are sclerosing adnexal neoplasms with overlapping histopathologic features. We compared cytokeratin 15, (CK15), T-cell death-associated gene 51 (TDAG51), cytokeratin 20 (CK20) and androgen receptor (AR) in differentiating these tumors and assessed their expression in BCC subtypes.
  
  
  METHODS
  Fifteen DTE, 15 infundibulocystic BCC, 18 micronodular BCC, 18 morpheaform BCC and 6 MAC were assessed for CK15, TDAG51, CK20 and AR expression.
  
  
  RESULTS
  Quantitative CK15 staining was higher in DTE compared with BCC (p < 0.0001) and MAC (p = 0.02). Quantitative TDAG51 staining was higher in DTE than BCC (p < 0.0001). The CK20+AR- immunophenotype was 100% sensitive and specific in diagnosing DTE. The CK20-AR+ immunophenotype was 95.24% specific and 83.33% sensitive for BCC. The CK20-AR- immunophenotype was 83.33% sensitive and 90.91% specific for MAC. CK15, CK20 and AR were positive in 87, 53 and 67% of infundibulocystic BCC cases, respectively.
  
  
  CONCLUSIONS
  Combination of CK20 and AR best differentiated these sclerosing adnexal neoplasms. Greater positivity for CK15 and TDAG51 generally favors benign lesions. Infundibulocystic BCC has higher CK20 and lower AR immunopositivity than other BCC variants and a high degree of CK15 and TDAG51 positivity.
authors.affiliation: Departments of Dermatology and Pathology, University of California, San Francisco, CA, USA.
authors.forename: Mara Therese P
authors.initials: MT
authors.lastname: Evangelista
authors.affiliation: Departments of Dermatology and Pathology, University of California, San Francisco, CA, USA.
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: North
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D002280:Basal Cell Carcinoma / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D053569:Keratin-15 / Q000378:metabolism*; D053554:Keratin-20 / Q000378:metabolism*; D018294:Neoplasms, Adnexal and Skin Appendage / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology; D011944:Receptors, Androgen / Q000378:metabolism*; D012878:Skin Neoplasms / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: C410798:AR protein, human; D014408:Biomarkers, Tumor; D053569:Keratin-15; D053554:Keratin-20; C491923:PHLDA1 protein, human; D011944:Receptors, Androgen; D014157:Transcription Factors
keywords: CK15; desmoplastic trichepithelioma; infundibulocystic basal cell carcinoma; microcystic adnexal carcinoma; morpheaform basal cell carcinoma