title: Repeated dedifferentiation of low-grade intraosseous osteosarcoma.
abstract: Low-grade intraosseous osteosarcoma is an uncommon bone tumor that is characterized by minimum cytological atypism and a much better prognosis than conventional osteosarcoma. This report describes a patient who had a low-grade osteosarcoma that mimicked fibrous dysplasia (FD). The tumor had an area of high-grade sarcoma at the initial diagnosis. Ten years after incomplete resection of FD-like tumor, local recurrence with areas of high-grade tumor developed. This case illustrates the potential of dedifferentiation in low-grade intraosseous osteosarcoma.
authors.affiliation: Department of Orthopedic Surgery and Pathology, Niigata University School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ogose
authors.forename: T
authors.initials: T
authors.lastname: Hotta
authors.forename: I
authors.initials: I
authors.lastname: Emura
authors.forename: S
authors.initials: S
authors.lastname: Imaizumi
authors.forename: M
authors.initials: M
authors.lastname: Takeda
authors.forename: S
authors.initials: S
authors.lastname: Yamamura
mesh_terms: D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D005357:Fibrous Dysplasia of Bone / Q000473:pathology; D006801:Humans; D006811:Humerus / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D012516:Osteosarcoma / Q000000981:diagnostic imaging / Q000473:pathology*; D011859:Radiography; D012509:Sarcoma / Q000473:pathology