title: Malignant transformation of atypical oral lichen planus: a review of 32 cases.
abstract: OBJECTIVE
  To assess the prevalence of malignant transformation of atypical lichen planus in our medium and describe the clinico-pathological features of the cases that had a premalignant potential.
  
  
  METHODS
  we performed a retrospective analysis of the records of patients seen at the Stomatology Department of the School of Dentistry, University of Buenos Aires, during the period 1991-1997. A total of 719 patients (7.02%) had oral lichen planus (481 women and 238 men). From a clinico-pathological point of view, 228 (31.7%) were typical forms and 491 (68.3%) were atypical forms. In all of the cases, lichen planus was confirmed histologically and a clinical protocol was followed.
  
  
  RESULTS
  Thirty-two (6.51%) patients were known to have developed malignant changes. In these cases the lesions had been diagnosed as atypical lichen planus at the outset. The most frequent clinical presentations were the keratotic (plaque-like) and erosive forms. Most of the lesions were on the tongue. The results support a premalignant potential for atypical lichen planus.
  
  
  CONCLUSIONS
  Oral lichen planus is a precancerous condition. The atypical form, particularly in its keratotic and erosive presentations, has a premalignant potential in our medium. The most frequent localization is the tongue.
authors.affiliation: Catedra de Patologia y Clinica Bucodental II. Facultad de Odontologia. Universidad de Buenos Aires. postmast@pcbd2.odont.uba.ar
authors.forename: Héctor Eduardo
authors.initials: HE
authors.lastname: Lanfranchi-Tizeira
authors.forename: Silvia Cristina
authors.initials: SC
authors.lastname: Aguas
authors.forename: Susana Mariela
authors.initials: SM
authors.lastname: Sano
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002471:Cell Transformation, Neoplastic; D005260:Female; D006801:Humans; D017676:Lichen Planus, Oral / Q000453:epidemiology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000453:epidemiology / Q000473:pathology*; D012189:Retrospective Studies