Pleomorphic Liposarcoma : Microscopic Features

Comments:
Microscopic Features: The diagnostic feature of a pleomorphic liposarcoma (PLS) is the presence of highly pleomorphic lipoblasts with bizarre hyperchromatic nuclei in a background of a high-grade sarcoma. Some of the tumor giant cells have acidophilic cytoplasm with eosinophilic hyaline droplets.

Given the uneven distribution of lipoblasts, thorough sampling of the tumor is necessary. PLS with scant number of lipoblasts are commonly diagnosed as undifferentiated pleomorphic sarcoma or rhabdomyosarcoma. Areas of well-differentiated liposarcoma are absent. Necrosis is seen in 50% of cases. Abnormal mitoses are frequent (see lower left corner).