title: GATA3 expression in primary vulvar Paget disease: a potential pitfall leading to misdiagnosis of pagetoid urothelial intraepithelial neoplasia.
abstract: GATA3 has been reported as a specific urothelial marker among organs in the pelvic region, and has been classified as highly sensitive and specific for urothelial and breast carcinomas. Our aim was to verify GATA3 expression in extramammary Paget disease, and to determine whether it can be use to differentiate primary vulvar Paget disease from pagetoid urothelial intraepithelial neoplasia (PUIN). We also analysed HER2 protein expression and HER2 gene amplification and their roles as prognostic factors in extramammary Paget disease.
  
  
  
  We analysed GATA3 and HER2 expression in 11 primary vulvar Paget disease cases and two PUIN cases. All cases showed nuclear expression of GATA3. Of 13 cases, five were equivocal for HER2 expression (score 2+) and one was positive (3+). Fluorescence in-situ hybridization results showed amplification in two of these six cases. Both HER2-amplified cases were invasive.
  
  
  
  GATA3 was positive in all extramammary Paget disease cases tested (13 cases), and it has no value for differentiating between primary and secondary vulvar Paget disease from the urological tract. HER2 amplification might confer an aggressive and invasive pattern in primary vulvar Paget disease, as both amplified cases showed an invasive pattern.
authors.affiliation: Department of Pathology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Diogo
authors.initials: D
authors.lastname: Morbeck
authors.affiliation: Department of Pathology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Aline C
authors.initials: AC
authors.lastname: Tregnago
authors.affiliation: Department of Gynecology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Glauco
authors.initials: G
authors.lastname: Baiocchi
authors.affiliation: Department of Urology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Carlos
authors.initials: C
authors.lastname: Sacomani
authors.affiliation: Department of Pathology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Peresi
authors.affiliation: Department of Pathology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Cynthia T
authors.initials: CT
authors.lastname: Osório
authors.affiliation: Instituto de Anatomia Patológica, Piracicaba, Brazil.
authors.forename: Luciana
authors.initials: L
authors.lastname: Schutz
authors.affiliation: Department of Pathology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Stephania M
authors.initials: SM
authors.lastname: Bezerra
authors.affiliation: Department of Pathology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Louise
authors.initials: L
authors.lastname: de Brot
authors.affiliation: Department of Pathology, AC Camargo Cancer Center, São Paulo, Brazil.
authors.forename: Isabela W
authors.initials: IW
authors.lastname: Cunha
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D003951:Diagnostic Errors; D005260:Female; D050990:GATA3 Transcription Factor / Q000032:analysis / Q000096:biosynthesis*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D010145:Paget Disease, Extramammary / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D014571:Urologic Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D014846:Vulvar Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D050990:GATA3 Transcription Factor; D018719:Erb-b2 Receptor Tyrosine Kinases; C494749:GATA3 protein, human; C508053:ERBB2 protein, human
keywords: GATA3; extramammary Paget disease; pagetoid urothelial intraepithelial neoplasia; vulvar Paget disease