title: Case report: natural development of osteosarcoma from precancerous lesion.
abstract: We encountered a very rare case that suggested the natural development of osteosarcoma from a precancerous lesion. The patient presented with a huge osteosarcoma in the distal femur on the initial consultation to our hospital. He had undergone X-ray examination twice previously, due to a knee injury. The findings of the lesion detected by the first X-ray examination were similar to a fibrous cortical defect (FCD), differing from those of an osteosarcoma lesion detected by second and last X-ray examinations. We retrospectively estimated the growth rate of the FCD-like and osteosarcoma lesions and found that FCD-like lesion was not osteosarcoma, but might have been a precancerous lesion. We also speculated that this osteosarcoma lesion might have appeared 18 months before the patient consulted our hospital.
authors.affiliation: Department of Orthopaedic Surgery, Kyoto Prefectural University of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Suginoshita
authors.forename: K
authors.initials: K
authors.lastname: Kusuzaki
authors.forename: T
authors.initials: T
authors.lastname: Nagaoka
authors.forename: H
authors.initials: H
authors.lastname: Murata
authors.forename: M
authors.initials: M
authors.lastname: Hirata
authors.forename: S
authors.initials: S
authors.lastname: Hashiguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Hirasawa
mesh_terms: D000058:Accidental Falls; D000328:Adult; D003288:Contusions / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D018450:Disease Progression; D017809:Fatal Outcome; D005266:Femoral Neoplasms / Q000000981:diagnostic imaging* / Q000209:etiology; D005269:Femur / Q000000981:diagnostic imaging* / Q000473:pathology; D005355:Fibrosis; D006801:Humans; D007718:Knee Injuries / Q000000981:diagnostic imaging*; D008297:Male; D010014:Osteolysis / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology; D012516:Osteosarcoma / Q000000981:diagnostic imaging* / Q000209:etiology; D010026:Osteosclerosis / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000473:pathology; D011230:Precancerous Conditions / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000473:pathology; D011859:Radiography