title: A giant radiopaque mass in the masticatory space.
abstract: A 2-year-old boy presented with a giant mass in the masticatory space. The mass exhibited a lobulating ossification, with no attachment to the adjacent normal bone. An enucleation was performed under the tentative diagnosis of extra-articular synovial chondromatosis, benign ossifying neoplasm, non-neoplastic heterotopic ossification, or low-grade malignancy. Upon microscopic examination, the excised mass was composed of multiple osteocartilaginous areas. We hereby present detailed clinicopathological findings.
authors.affiliation: Lecturer, Department of Pathology, School of Dentistry, Seoul National University, Seoul, Korea.
authors.forename: Young-Ah
authors.initials: YA
authors.lastname: Cho
authors.forename: Hye-Jung
authors.initials: HJ
authors.lastname: Yoon
authors.forename: Seong-Doo
authors.initials: SD
authors.lastname: Hong
authors.forename: Jae-Il
authors.initials: JI
authors.lastname: Lee
authors.forename: Sam-Pyo
authors.initials: SP
authors.lastname: Hong
mesh_terms: D002675:Child, Preschool; D002812:Chondroma / Q000175:diagnosis; D015838:Chondromatosis, Synovial / Q000175:diagnosis; D002813:Chondrosarcoma / Q000175:diagnosis; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008406:Masseter Muscle / Q000000981:diagnostic imaging* / Q000473:pathology; D019042:Muscle Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D009221:Myositis Ossificans / Q000175:diagnosis; D015831:Osteochondroma / Q000000981:diagnostic imaging* / Q000473:pathology; D011859:Radiography; D013705:Temporomandibular Joint Disorders / Q000175:diagnosis