title: The natural course of preneoplastic lesions in bronchial epithelium.
abstract: OBJECTIVE
  To study the natural history of preneoplastic lesions in the bronchial mucosa of the individuals at risk.
  
  
  METHODS
  White light and autofluorescence bronchoscopy examinations have been done in 52 individuals harboring 134 preneoplastic lesions (WHO criteria). End points were the development of carcinoma in situ (CIS) or squamous cell cancer (SCC) or the highest category of dysplasia up until March 1, 2003 for the remaining preneoplastic lesions.
  
  
  RESULTS
  Distribution and outcome of preneoplastic lesions have been found to be unrelated to various risk factors such as smoking history, past history of cancer, or chronic obstructive pulmonary disease. Nonstepwise changes of preneoplastic lesions are seen. Regression rate has been 54%. Progression to CIS/SCC has been 13.4% (18 of 134) and was for severe dysplasia, significantly higher (P < 0.003) than preneoplastic lesions showing lower-grade dysplasia (squamous metaplasia, mild and moderate dysplasia). Time to progression was not significantly different. However, when analyzed per individual, no significant difference of progression rate between individuals with or without severe dysplasia was seen (39% versus 26%; P = 0.36).
  
  
  CONCLUSIONS
  The 54% regression rate of all preneoplastic lesions, 26% to 39% progression rate to CIS/SCC of individuals with lower-grade dysplasia or severe dysplasia with no significant difference in progression rate and time to progression combined with nonstepwise histologic changes unrelated to the initial histologic grading indicate that one cannot differentiate the potentially more malignant preneoplastic lesions among the many preneoplastic lesions present in the bronchial mucosa. The initial WHO classification of any preneoplastic lesion cannot be reliably used for accurate risk assessment of field carcinogenesis.
authors.affiliation: Department of Pulmonology, Vrije Universiteit Medical Center, 1007 MB Amsterdam, the Netherlands.
authors.forename: Roderick H
authors.initials: RH
authors.lastname: Breuer
authors.forename: Arifa
authors.initials: A
authors.lastname: Pasic
authors.forename: Egbert F
authors.initials: EF
authors.lastname: Smit
authors.forename: Esther
authors.initials: E
authors.lastname: van Vliet
authors.forename: Anton
authors.initials: A
authors.lastname: Vonk Noordegraaf
authors.forename: Elle J
authors.initials: EJ
authors.lastname: Risse
authors.forename: Pieter E
authors.initials: PE
authors.lastname: Postmus
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Sutedja
mesh_terms: D000328:Adult; D000368:Aged; D001980:Bronchi / Q000473:pathology*; D001999:Bronchoscopy; D002278:Carcinoma in Situ / Q000175:diagnosis / Q000209:etiology; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000209:etiology; D002471:Cell Transformation, Neoplastic; D018450:Disease Progression; D004848:Epithelium / Q000473:pathology*; D005260:Female; D005453:Fluorescence; D006801:Humans; D008027:Light; D008175:Lung Neoplasms / Q000145:classification / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012307:Risk Factors