title: Retroperitoneal dedifferentiated liposarcoma with osteosarcomatous components: a case report.
abstract: We report a rare case of recurrent retroperitoneal dedifferentiated liposarcoma with osteosarcomatous components. An 82-year-old male diagnosed with recurrent retroperitoneal liposarcoma underwent a tumor resection. Histologically, osseous matrix with osteoid and mature hyaline cartilaginous tissues with high cellularity were observed in a fibrous background through most of the tumor, and scattered MDM2- and CDK4-positive atypical hyperchromatic stromal cells were detected surrounding the dedifferentiated areas. Dedifferentiation occurs in up to 10% of well-differentiated liposarcomas, frequently resembling a malignant fibrous histiocytoma-like pleomorphic sarcoma. In contrast, divergent differentiation with osteosarcomatous components is considered to be extremely rare.
authors.affiliation: Department of Surgery, Okaya Municipal Hospital, Hon-machi 4-11-33, Okaya, 394-8512, Japan.
authors.forename: Taishi
authors.initials: T
authors.lastname: Fujii
authors.forename: Takuma
authors.initials: T
authors.lastname: Arai
authors.forename: Masahiro
authors.initials: M
authors.lastname: Sakon
authors.forename: Shinji
authors.initials: S
authors.lastname: Sawano
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Momose
authors.forename: Keiko
authors.initials: K
authors.lastname: Ishii
authors.forename: Shiro
authors.initials: S
authors.lastname: Miwa
mesh_terms: D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D054337:Cell Dedifferentiation; D051358:Cyclin-Dependent Kinase 4 / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D008080:Liposarcoma / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000473:pathology* / Q000601:surgery; D012516:Osteosarcoma / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D011237:Predictive Value of Tests; D051736:Proto-Oncogene Proteins c-mdm2 / Q000032:analysis; D012086:Reoperation; D012186:Retroperitoneal Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; C495900:CDK4 protein, human; D051358:Cyclin-Dependent Kinase 4
keywords: Dedifferentiated liposarcoma; osteosarcoma; retroperitoneum