Myxoid Liposarcoma, High-Grade

Comments:
Myxoid Liposarcoma, High-Grade (Round Cell LPS): The tumor cells are larger, primitive-appearing with a high nucleus/cytoplasm ratio, a prominent nucleolus and scant cytoplasm. They are arranged back-to-back in compact sheets without much myxoid stroma, imparting a basophilic appearance at low magnification.

The tumor cells may also form trabeculae or cords. Lipoblasts and plexiform capillary network are less prominent than myxoid LPS. The percentage of high-grade areas should be documented in the pathology report. The tumor may be combined myxoid and round cell LPS or pure round cell LPS. The high-grade areas harbor the same translocations as myxoid LPS.