title: Radiation-induced dedifferentiated chondrosarcoma with orbital invasion.
abstract: OBJECTIVE
  To report 2 interventional cases of dedifferentiated chondrosarcoma with orbital involvement after radiotherapy performed in childhood and to review the literature on chondrosarcoma in the orbit following radiation treatment.
  
  
  METHODS
  Retrospective analysis of medical records of 2 patients with chondrosarcoma of the orbits with review of the literature.
  
  
  RESULTS
  The first patient developed chondrosarcoma of the orbital and maxillary sinus 36 years after external beam radiation therapy to the OS to treat retinoblastoma. The second patient developed a large orbital chondrosarcoma 35 years after external beam radiation therapy in the treatment of craniofacial fibrous dysplasia.
  
  
  CONCLUSIONS
  These cases highlight the risk of secondary chondrosarcoma in patients following radiotherapy and the importance of lifetime monitoring.
authors.affiliation: *Department of Ophthalmology, Oculoplastic and Orbital Surgery, University of Colorado Hospital, Aurora, Colorado; †Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland; ‡Department of Pathology, Denver Health Medical Center; §Colorado Head and Neck Specialists, Denver, Colorado, U.S.A.; ‖Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, University of São Paulo, School of Medicine of Ribeirão Preto, São Paulo, Brazil; ¶King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia; #Otolaryngology, Head and Neck Surgery, University of Colorado Hospital, Aurora, Colorado; and **Texas Oculoplastic Consultants, Austin, Texas, U.S.A.
authors.forename: Brett W
authors.initials: BW
authors.lastname: Davies
authors.forename: Christina R
authors.initials: CR
authors.lastname: Prescott
authors.forename: Sherif A
authors.initials: SA
authors.lastname: Said
authors.forename: John
authors.initials: J
authors.lastname: Campana
authors.forename: Flávia A
authors.initials: FA
authors.lastname: Attié-Castro
authors.forename: Antonio Augusto
authors.initials: AA
authors.lastname: Velasco E Cruz
authors.forename: Vikram D
authors.initials: VD
authors.lastname: Durairaj
mesh_terms: D000328:Adult; D054337:Cell Dedifferentiation; D002813:Chondrosarcoma / Q000175:diagnosis / Q000209:etiology*; D003037:Cobalt Radioisotopes / Q000009:adverse effects*; D005147:Facial Bones / Q000473:pathology*; D017809:Fatal Outcome; D005260:Female; D005357:Fibrous Dysplasia of Bone / Q000532:radiotherapy; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009361:Neoplasm Invasiveness; D009381:Neoplasms, Radiation-Induced / Q000175:diagnosis / Q000209:etiology*; D009918:Orbital Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D019572:Retinal Neoplasms / Q000532:radiotherapy; D012175:Retinoblastoma / Q000532:radiotherapy; D012888:Skull Neoplasms / Q000175:diagnosis / Q000209:etiology*; D014057:Tomography, X-Ray Computed
chemical_list: D003037:Cobalt Radioisotopes