title: Significance of autofluorescence for the optical demarcation of field cancerisation in the upper aerodigestive tract.
abstract: BACKGROUND
  Second primaries in the upper aerodigestive tract (UADT) are increasingly related to bad prognosis. So early detection of small cancer foci is required to improve the survival rate. Here, autofluorescence (AF) might become useful as in vivo biochemical changes of cancer metabolism can be shown by fluorescence.
  
  
  METHODS
  For more exact data on AF in cancerous lesions 32 cancer specimens of the UADT and 57 specimens of normal oral mucosa as a control group were examined by using autofluorescent microscopy and spectroscopy, the tissue being activated with light at 365 nm wavelength. Video-controlled in vivo fluorescence examinations in field cancerisation of the UADT were also investigated and compared with pathohistological findings.
  
  
  RESULTS
  The intensity of AF of the connective tissue was observed to increase at the tumour border. Contrary to results in the literature, no homogeneous fluorescence gradient could be proved between marginal epithelium and the tumour itself. The brightly shining submucosal elastic fibres allowed fluorescent spectroscopic detection of the tumour margins in vitro in 71%. Even small precancerous lesions were traced in vivo mainly by keratinization when using the autofluorescence diagnostic imaging system.
  
  
  CONCLUSIONS
  Our examination proved a multi-factorial genesis of autofluorescence with strong inter-individual variations. Preliminary clinical examination showed that this method can be applied as an additional tool for early detection of cancerous lesions in the UADT.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Justus-Liebig-University of Giessen, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Fryen
authors.forename: H
authors.initials: H
authors.lastname: Glanz
authors.forename: W
authors.initials: W
authors.lastname: Lohmann
authors.forename: T
authors.initials: T
authors.lastname: Dreyer
authors.forename: R M
authors.initials: RM
authors.lastname: Bohle
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000175:diagnosis*; D005453:Fluorescence; D006801:Humans; D007822:Laryngeal Neoplasms / Q000175:diagnosis*; D009959:Oropharyngeal Neoplasms / Q000175:diagnosis; D010610:Pharyngeal Neoplasms / Q000175:diagnosis*