title: Fluorescence visualization detection of field alterations in tumor margins of oral cancer patients.
abstract: OBJECTIVE
  Genetically altered cells could become widespread across the epithelium of patients with oral cancer, often in clinically and histologically normal tissue, and contribute to recurrent disease. Molecular approaches have begun to yield information on cancer/risk fields; tissue optics could further extend our understanding of alteration to phenotype as a result of molecular change.
  
  
  METHODS
  We used a simple hand-held device in the operating room to directly visualize subclinical field changes around oral cancers, documenting alteration to fluorescence. A total of 122 oral mucosa biopsies were obtained from 20 surgical specimens with each biopsy being assessed for location, fluorescence visualization (FV) status, histology, and loss of heterozygosity (LOH; 10 markers on three regions: 3p14, 9p21, and 17p13).
  
  
  RESULTS
  All tumors showed FV loss (FVL). For 19 of the 20 tumors, the loss extended in at least one direction beyond the clinically visible tumor, with the extension varying from 4 to 25 mm. Thirty-two of 36 FVL biopsies showed histologic change (including 7 squamous cell carcinoma/carcinomas in situ, 10 severe dysplasias, and 15 mild/moderate dysplasias) compared with 1 of the 66 FV retained (FVR) biopsies. Molecular analysis on margins with low-grade or no dysplasia showed a significant association of LOH in FVL biopsies, with LOH at 3p and/or 9p (previously associated with local tumor recurrence) present in 12 of 19 FVL biopsies compared with 3 of 13 FVR biopsies (P=0.04).
  
  
  CONCLUSIONS
  These data have, for the first time, shown that direct FV can identify subclinical high-risk fields with cancerous and precancerous changes in the operating room setting.
authors.affiliation: Faculty of Dentistry, University of British Columbia, Department of Cancer Control Research, and Department of Surgery, Vancouver General Hospital, Vancouver, British Columbia, Canada.
authors.forename: Catherine F
authors.initials: CF
authors.lastname: Poh
authors.forename: Lewei
authors.initials: L
authors.lastname: Zhang
authors.forename: Don W
authors.initials: DW
authors.lastname: Anderson
authors.forename: J Scott
authors.initials: JS
authors.lastname: Durham
authors.forename: P Michele
authors.initials: PM
authors.lastname: Williams
authors.forename: Robert W
authors.initials: RW
authors.lastname: Priddy
authors.forename: Ken W
authors.initials: KW
authors.lastname: Berean
authors.forename: Samson
authors.initials: S
authors.lastname: Ng
authors.forename: Olivia L
authors.initials: OL
authors.lastname: Tseng
authors.forename: Calum
authors.initials: C
authors.lastname: MacAulay
authors.forename: Miriam P
authors.initials: MP
authors.lastname: Rosin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics; D002278:Carcinoma in Situ / Q000175:diagnosis; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000235:genetics / Q000601:surgery*; D005260:Female; D005453:Fluorescence; D006801:Humans; D006838:Hydrocarbons; D007432:Intraoperative Period; D019656:Loss of Heterozygosity; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000601:surgery*; D018570:Risk Assessment
chemical_list: D014408:Biomarkers, Tumor; D006838:Hydrocarbons; C013089:ligroin