title: The occurrence of keratocystic odontogenic tumours in nevoid basal cell carcinoma syndrome.
abstract: OBJECTIVE
  This retrospective study reviews the occurrence of keratocystic odontogenic tumours (KOTs) in nevoid basal cell carcinoma syndrome (NBCCS) patients seen in the Oral and Maxillofacial Radiology Special Procedures Clinic in the Faculty of Dentistry at the University of Toronto.
  
  
  METHODS
  This study examines the number and radiographic features of KOTs identified in 11 NBCCS patients who presented with 43 KOTs between January 1989 and 30 June 2007 on plain film radiographs and CT.
  
  
  RESULTS
  Regression analysis revealed a statistically significant (P < 0.01) relationship between the age at first KOT occurrence and the total number of lifetime KOTs (r = -0.78). Of the KOTs identified, 25 developed in the mandible and 18 developed in the maxillae. The majority of these were associated with a change in either the size or shape of the follicular space, and both plain film radiography and CT were equally effective at demonstrating these changes. CT was, however, more effective at demonstrating endosteal scalloping of cortical bone than plain film radiography (P < 0.001) while the opposite was true for showing tooth displacement (P < 0.01). For patients imaged with both plain radiography and CT (29 KOTs), 5 KOTs were detectable only by CT.
  
  
  CONCLUSIONS
  Our results suggest that there should be early and frequent monitoring of NBCCS patients for the development of KOTs in youth and adolescence, and that CT imaging should play an important role in these investigations.
authors.affiliation: The University of Toronto, ON, Canada. ernest.lam@dentistry.utoronto.ca
authors.forename: E W N
authors.initials: EW
authors.lastname: Lam
authors.forename: L
authors.initials: L
authors.lastname: Lee
authors.forename: S E
authors.initials: SE
authors.lastname: Perschbacher
authors.forename: M J
authors.initials: MJ
authors.lastname: Pharoah
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001478:Basal Cell Nevus Syndrome / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology*; D016009:Chi-Square Distribution; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009808:Odontogenic Tumors / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology*; D009864:Ontario / Q000453:epidemiology; D015995:Prevalence; D011862:Radiography, Panoramic; D012044:Regression Analysis; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed