title: Dedifferentiated Liposarcoma of the Retroperitoneum With Heterologous Osteosarcomatous Differentiation and a Striking Aneurysmal Bone Cyst-Like Morphology.
abstract: A 69-year-old woman with a 10-year medical history of recurrent retroperitoneal dedifferentiated liposarcoma presented with a 3-cm large hemorrhagic and multicystic left-sided retroperitoneal mass. Histopathological examination of the resected specimen showed a heterogeneous, high-grade mesenchymal nonlipogenic tumor with areas of osteoblastic/osteosarcomatous differentiation and aneurysmal bone cyst-like features. Based on the clinical presentation, the morphology, and the supportive immunohistochemical and molecular findings (MDM2 overexpression and amplification of the MDM2 gene, respectively), a diagnosis of a dedifferentiated liposarcoma with heterologous osteosarcomatous differentiation and an aneurysmal bone cyst-like morphology was made. To the best of our knowledge, this is the first description of aneurysmal bone cyst-like morphology in dedifferentiated liposarcoma, further expanding the broad morphological spectrum of dedifferentiated liposarcoma.
authors.affiliation: 1 Ghent University Hospital, Ghent University, Ghent, Belgium.
authors.forename: Carole
authors.initials: C
authors.lastname: Van Haverbeke
authors.affiliation: 1 Ghent University Hospital, Ghent University, Ghent, Belgium.
authors.forename: Jo
authors.initials: J
authors.lastname: Van Dorpe
authors.affiliation: 1 Ghent University Hospital, Ghent University, Ghent, Belgium.
authors.forename: Evelyne
authors.initials: E
authors.lastname: Lecoutere
authors.affiliation: 2 Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Uta
authors.initials: U
authors.lastname: Flucke
authors.affiliation: 1 Ghent University Hospital, Ghent University, Ghent, Belgium.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Ferdinande
authors.affiliation: 1 Ghent University Hospital, Ghent University, Ghent, Belgium.
authors.forename: David
authors.initials: D
authors.lastname: Creytens
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008080:Liposarcoma / Q000473:pathology*; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D012186:Retroperitoneal Neoplasms / Q000473:pathology*
keywords: MDM2; aneurysmal bone cyst; dedifferentiated liposarcoma; liposarcoma; osteosarcomatous