title: Enchondroma of the nasal septum due to Ollier disease: a case report and review of the literature.
abstract: BACKGROUND
  Morbus Ollier is characterized by the presence of multiple enchondromas (ie, benign intraosseous cartilaginous lesions). Although their manifestation in the limb bones is well described, only a few cases with ear, nose, and throat (ENT) involvement, primarily arising from the skull, have been reported. The malignant transformation toward slowly growing low-grade chondrosarcomas is the most severe form of progression.
  
  
  METHODS
  We report a unique case of a 54-year-old patient with Ollier disease with an extensive nasal enchondroma apparently eroding the middle nasal concha and expanding to the lateral nasal wall that raised suspicion of malignant transformation.
  
  
  RESULTS
  Radiological and histological features of enchondromas can be controversial and seem to have limited sensitivity to exclude low-grade malignancy. The clinical symptoms play a decisive role in differentiation between enchondromas and low-grade chondrosarcomas.
  
  
  CONCLUSIONS
  Surgery remains the only effective solution in removing an enchondroma and preventing the tendency toward malignant transformation.
authors.affiliation: Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Zurich, Zurich, Switzerland; Medical School of the Technical University Munich, Munich, Germany.
authors.forename: Christian M C
authors.initials: CM
authors.lastname: Jacobi
authors.forename: Egodage Samitha
authors.initials: ES
authors.lastname: Hiranya
authors.forename: Annietta
authors.initials: A
authors.lastname: Gay
authors.forename: David
authors.initials: D
authors.lastname: Holzmann
authors.forename: Spyridon
authors.initials: S
authors.lastname: Kollias
authors.forename: Michael B
authors.initials: MB
authors.lastname: Soyka
mesh_terms: D001707:Biopsy, Needle; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D002812:Chondroma / Q000473:pathology* / Q000601:surgery; D004687:Enchondromatosis / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D005269:Femur / Q000473:pathology*; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009300:Nasal Septum / Q000601:surgery*; D009669:Nose Neoplasms / Q000473:pathology* / Q000601:surgery; D018570:Risk Assessment; D016896:Treatment Outcome
keywords: Ollier disease; chondrosarcoma; enchondroma; multiple enchondromatosis; nasal septum