Parosteal osteosarcoma associated with a low-grade component mimicking well-differentiated liposarcoma: a case report


Parosteal osteosarcomas and well-differentiated liposarcomas are both well-differentiated locally aggressive tumors. They both have simple karyotypes with amplification of the 12q13-15 regions including MDM2 and CDK4 genes. In this report, we describe the case of a parosteal osteosarcoma intertwined with a low-grade component similar to a well-differentiated liposarcoma. The association of a bone component with an adipose component was initially overlooked. We describe the histological, imaging, and molecular characteristics of this tumor stressing the importance of radio-pathological correlation. To our knowledge, this is the second report of a parosteal osteoliposarcoma. Awareness of this rare presentation may allow radiologists and surgeons to recognize the peripheral fatty component as an integral part of the tumor.

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Correspondence to F. Larousserie.

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This case was awarded the Corinne Farrell Best Case Report Presentation at the 2013 ISS Members’ Meeting.

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Sohier, P., Rodrigues, M., Anract, P. et al. Parosteal osteosarcoma associated with a low-grade component mimicking well-differentiated liposarcoma: a case report. Skeletal Radiol (2020).

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  • Parosteal osteosarcoma
  • Well-differentiated liposarcoma
  • Parosteal osteoliposarcoma
  • Radio-pathological correlation