title: Reproducibility of biopsy diagnoses of endometrial hyperplasia: evidence supporting a simplified classification.
abstract: BACKGROUND
  Identifying which categories in the World Health Organization classification of endometrial hyperplasia contribute to suboptimal reproducibility is clinically important.
  
  
  METHODS
  A 2-member panel reviewed 209 endometrial biopsy/curettage specimens originally diagnosed as incident endometrial hyperplasia as part of a progression study. Original diagnoses included the following: disordered proliferative endometrium, simple hyperplasia, complex hyperplasia, and atypical hyperplasia; panel diagnoses also included negative and carcinoma. We assessed percentage agreement and kappa statistics+/-standard errors (K+/-SE).
  
  
  RESULTS
  Original and panel diagnoses (combining negative with disordered proliferative endometrium; atypical hyperplasia with carcinoma) agreed for 34.9% of biopsies (K-unweighted+/-SE=0.18+/-0.03; K-weighted+/-SE=0.27+/-0.04). Panelists' diagnoses agreed (using 6 categories) for 51.7% of biopsies, corresponding to K-unweighted+/-SE=0.37+/-0.03, improving with weighting to K-weighted+/-SE=0.63+/-0.05. Reproducibility based on a 2-tier classification ([negative, disordered proliferative endometrium, simple hyperplasia, or complex hyperplasia] versus [atypical hyperplasia or carcinoma]) increased agreement between original and panel diagnoses to 82.8%, K-unweighted+/-SE=0.37+/-0.06, and between panelists to 87.0%, K-unweighted+/-SE=0.63+/-0.07. Agreement between panelists at a cutpoint of complex hyperplasia and more severe versus simple hyperplasia or less severe was 88.0%, K-unweighted+/-SE=0.72+/-0.07.
  
  
  CONCLUSIONS
  Developing and prospectively testing a binary system of classifying endometrial hyperplasia on endometrial biopsy may aid efforts to improve interobserver reproducibility.
authors.affiliation: Cancer Epidemiology and Genetics, The National Cancer Institute, 6120 Executive Blvd, Room 5028, Rockville, MD 20892-7374, USA. shermanm@mail.nih.gov
authors.forename: Mark E
authors.initials: ME
authors.lastname: Sherman
authors.forename: Brigitte M
authors.initials: BM
authors.lastname: Ronnett
authors.forename: Olga B
authors.initials: OB
authors.lastname: Ioffe
authors.forename: Douglas A
authors.initials: DA
authors.lastname: Richesson
authors.forename: Brenda B
authors.initials: BB
authors.lastname: Rush
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Glass
authors.forename: Nilanjan
authors.initials: N
authors.lastname: Chatterjee
authors.forename: Maire A
authors.initials: MA
authors.lastname: Duggan
authors.forename: James V
authors.initials: JV
authors.lastname: Lacey
mesh_terms: D001706:Biopsy; D004714:Endometrial Hyperplasia / Q000145:classification* / Q000473:pathology*; D005260:Female; D006801:Humans; D015203:Reproducibility of Results