title: Endometrial intraepithelial neoplasia.
abstract: BACKGROUND
  Developed in conjunction with molecular and progression data, the sequence classification schema for endometrial intraepithelial neoplasia (EIN)/benign hyperplasia (BH) provides an easy to adopt and reproducible method for classification of endometrial biopsies.
  
  
  OBJECTIVE
  To review current data supporting the use of BH/EIN to classify endometrial biopsies, and to discuss the hormone-driven endometrial sequence from anovulation/disordered proliferative endometrium through BH and EIN and their diagnostic difficulty.
  
  
  METHODS
  A comprehensive review of EIN literature based on literature indexed by PubMed (National Library of Medicine) and Google Scholar.
  
  
  CONCLUSIONS
  The BH/EIN schema is gaining wider acceptance among pathologist and clinicians. The research leading to the EIN criteria is based on molecular and progression data. The BH/EIN schema has better reproducibility among pathologists, is intuitively easy to use, and requires understanding of endometrial physiology and neoplasia.
authors.affiliation: From the Department of Pathology, University of Arkansas for Medical Sciences, Little Rock.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Owings
authors.forename: Charles M
authors.initials: CM
authors.lastname: Quick
mesh_terms: D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D003937:Diagnosis, Differential; D004714:Endometrial Hyperplasia / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D016889:Endometrial Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D004717:Endometrium / Q000473:pathology; D005260:Female; D006801:Humans; D008679:Metaplasia; D009154:Mutation; D051762:PAX2 Transcription Factor / Q000235:genetics; D051059:PTEN Phosphohydrolase / Q000235:genetics
chemical_list: D051762:PAX2 Transcription Factor; C497318:PAX2 protein, human; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human