title: Paravertebral Well-Differentiated Liposarcoma with Low-Grade Osteosarcomatous Component: Case Report with 11-Year Follow-Up, Radiological, Pathological, and Genetic Data, and Literature Review.
abstract: Despite being one of the most frequent soft-tissue sarcomas, well-differentiated liposarcoma has never been reported near the spine. The authors present the case of a 67-year-old man with progressive history of back pain. Physical examination revealed a mass located within the right paravertebral muscles. MR and CT imaging showed a heavily ossified central mass surrounded by a peripheral fatty component. No connection with the underlying bone was detected on imagery and during surgery. After surgical resection, histopathological examination revealed a tumor harboring combined features of well-differentiated liposarcoma and low-grade osteosarcoma. Tumor cells displayed overexpression of MDM2, CDK4, and P16 by immunohistochemistry and CGH revealed amplification of 12q13-15 as the only genetic imbalance. MDM2 FISH analysis was performed but was inconclusive. The pathological, immunohistochemical, and genetic features, the differential diagnoses, and the therapeutic management of this unusual tumor are discussed. No complementary treatment was performed initially. Following first treatment, two recurrences occurred 6 and 9 years later, both displaying histological features similar to the first occurrence. Radiotherapy was started after the second recurrence. Follow-up shows no evidence of disease 11 years after initial diagnosis. This case was unusual due to the paravertebral location of the tumor and its divergent differentiation.
authors.affiliation: Department of Pathology, APHM, Marseille, France.
authors.forename: Nicolas
authors.identifier: 0000-0002-9882-2162
authors.initials: N
authors.lastname: Macagno
authors.affiliation: Department of Neurosurgery, APHM, Marseille, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Fuentes
authors.affiliation: Department of Pathology, University Hospital, Tours, France.
authors.forename: Gonzague
authors.identifier: 0000-0001-5987-4552
authors.initials: G
authors.lastname: de Pinieux
authors.affiliation: Department of Pathology, APHM, Marseille, France.
authors.forename: André
authors.initials: A
authors.lastname: Maues de Paula
authors.affiliation: Department of Oncology, APHM, Marseille, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Salas
authors.affiliation: Department of Orthopedic Surgery, APHM, Marseille, France.
authors.forename: Jean-Camille
authors.initials: JC
authors.lastname: Mattéi
authors.affiliation: Department of Oncology, APHM, Marseille, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Dupuis
authors.affiliation: Department of Pathology, APHM, Marseille, France.
authors.forename: Romain
authors.initials: R
authors.lastname: Appay
authors.affiliation: Department of Molecular Biology, Curie Institute, Paris, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Aurias
authors.affiliation: Department of Neurosurgery, APHM, Marseille, France.
authors.forename: Henry
authors.initials: H
authors.lastname: Dufour
authors.affiliation: Department of Pathology, APHM, Marseille, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Figarella-Branger
authors.affiliation: Department of Pathology, APHM, Marseille, France.
authors.forename: Corinne
authors.initials: C
authors.lastname: Bouvier