Pathology: pleomorphic liposarcoma

Pleomorphic liposarcoma

  • Sheets of adipocytes admixed with spindle cells

  • Clear-eosinophilic cytoplasm

  • Round-ovoid, hyperchromatic, and pleomorphic nuclei; mitotic activity conspicuous

  • Pleomorphic lipoblasts interspersed

  • Necrosis often present

  • FISH: MDM2 non-amplified

Pleomorphic liposarcoma

  • Sheets of polygonal cells

  • Clear-eosinophilic and vacuolated cytoplasm

  • Round-ovoid, hyperchromatic, and pleomorphic nuclei; occasional mitotic activity

  • IHC: negative for MDM2 and CDK4 (not shown)

Pleomorphic liposarcoma

  • Sheets of polygonal cells with peritheliomatous pattern

  • Eosinophilic and vacuolated cytoplasm

  • Round-ovoid, hyperchromatic, and pleomorphic nuclei; occasional mitotic activity

  • Abundant necrosis

  • FISH: MDM2 non-amplified

Pleomorphic liposarcoma

  • Sheets of epithelioid-spindle cells

  • Eosinophilic cytoplasm

  • Round-ovoid, hyperchromatic, and pleomorphic nuclei; mitotic activity conspicuous

  • Sheets of pleomorphic lipoblasts

  • Necrosis often present

  • FISH: MDM2 non-amplified

Pleomorphic liposarcoma

  • Fascicles of epithelioid-spindle cells

  • Abundant eosinophilic cytoplasm

  • Round-ovoid, hyperchromatic, and pleomorphic nuclei; mitotic activity conspicuous

  • Focal myxoid stroma; interspersed nests of pleomorphic lipoblast-like cells

  • FISH: MDM2 non-amplified


(reasonable to wonder: is this a discrete entity, or perhaps heterologous adipocytic differentiation in myxofibrosarcoma, or another high grade sarcoma?)