title: Interobserver reliability in the histopathologic diagnosis of oral pre-malignant and malignant lesions.
abstract: BACKGROUND
  The histologic classification of pre-cancerous and cancerous oral lesions has generally shown poor agreement between pathologists, but lesion and patient characteristics that may affect diagnostic reliability have not been explored.
  
  
  METHODS
  Eighty-seven clinically suspicious oral lesions biopsied from 81 patients with previous upper aerodigestive tract cancer were independently classified by their local pathologist and a central pathology committee. Interobserver reliability between the local pathologist and the central pathology committee was measured with weighted kappa (kappa w) statistics and corresponding 95% confidence intervals (CI).
  
  
  RESULTS
  The kappa w for pathologic diagnosis was 0.59 (95% CI: 0.45, 0.72), and was higher for lesions without inflammation (0.67 (95% CI: 0.53, 0.80) than inflamed lesions (-0.10 (95% CI: -0.27, 0.07)). Greatest agreement was seen for lesions located in the buccal mucosa/vestibule (kappa w = 0.68 (95% CI: 0.46, 0.91)) and tongue (kappa w = 0.62 (95% CI: 0.40, 0.84)). Least agreement was found for lip/labial mucosa lesions (kappa w = -0.04 (95% CI: -0.34, 0.27)). Punch biopsies (kappa w = 0.67 (95% CI: 0.54, 0.80)) had greater interobserver reliability than wedge biopsies (kappa w = 0.38 (95% CI: 0.12, 0.64)).
  
  
  CONCLUSIONS
  These data suggest that the presence of inflammation, lesion site, and biopsy technique modifies the reliability of oral lesion histologic diagnoses.
authors.affiliation: Department of Oral Medicine, School of Dentistry, Box 356370, University of Washington, Seattle, WA 98195-6370, USA. denafis@u.washington.edu
authors.forename: Dena J
authors.initials: DJ
authors.lastname: Fischer
authors.forename: Joel B
authors.initials: JB
authors.lastname: Epstein
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Morton
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Schwartz
mesh_terms: D000428:Alcohol Drinking; D001706:Biopsy; D002277:Carcinoma / Q000175:diagnosis / Q000556:secondary; D002278:Carcinoma in Situ / Q000175:diagnosis*; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000175:diagnosis; D007249:Inflammation / Q000175:diagnosis; D007972:Leukoplakia, Oral / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D015588:Observer Variation; D010339:Pathology, Oral / Q000592:standards*; D011230:Precancerous Conditions / Q000175:diagnosis*; D012307:Risk Factors; D012907:Smoking