title: Low-grade liposarcoma with osteosarcomatous dedifferentiation: radiological and histological features.
abstract: We describe the radiological and pathological findings of a rare case of a low-grade liposarcoma associated with a high-grade osteosarcomatous component in a 78-year-old woman. Pre-operative imaging demonstrated a well-encapsulated homogeneous fatty tumour in the right buttock deep to the gluteal musculature. Centrally within the fatty tumour a region of increased soft tissue attenuation on CT and heterogeneous high signal on fat-saturated T2-weighted MRI was seen with amorphous calcification/ossification. Histological assessment revealed a low-grade liposarcoma containing an area of dedifferentiation that resembled an osteosarcoma. We describe the radiological-pathological findings in this rarely reported clinical entity and discuss the differential diagnosis of calcification within lipomatous tumours.
authors.affiliation: Department of Medical Imaging, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario, M5G 1X5, Canada.
authors.forename: Andoni P
authors.initials: AP
authors.lastname: Toms
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: White
authors.forename: Rita
authors.initials: R
authors.lastname: Kandel
authors.forename: Robert S
authors.initials: RS
authors.lastname: Bell
mesh_terms: D000368:Aged; D002081:Buttocks; D002114:Calcinosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008080:Liposarcoma / Q000000981:diagnostic imaging* / Q000473:pathology; D019042:Muscle Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging*; D011859:Radiography