dedifferentiated liposarcoma with homologous lipoblastic differentiation
Dedifferentiated liposarcoma (LPS) is a malignant adipocytic neoplasm defined as the transition from well-differentiated LPS to a nonlipogenic sarcoma.
Heterologous differentiation is seen in 5% to 10% of dedifferentiated LPS, usually with myogenic or osteo/chondrosarcomatous elements.
Adipocytic differentiation in the dedifferentiated component is incompatible with the current definition of dedifferentiated LPS. Pleomorphic LPS is a high-grade sarcoma containing lipoblasts.
At least in areas, pleomorphic LPS can be indistinguishable from dedifferentiated LPS, except for the presence of lipoblasts in pleomorphic LPS and well-differentiated LPS areas in dedifferentiated LPS.
Dedifferentiated LPS can show lipoblastic differentiation in the high-grade component, resulting in areas indistinguishable from pleomorphic LPS.
The available clinical and molecular data support the notion of "homologous" lipoblastic differentiation in dedifferentiated LPS, rather than mixed-type LPS.
References
Dedifferentiated liposarcoma with "homologous" lipoblastic (pleomorphic liposarcoma-like) differentiation: clinicopathologic and molecular analysis of a series suggesting revised diagnostic criteria. Mariño-Enríquez A, Fletcher CD, Dal Cin P, Hornick JL. Am J Surg Pathol. 2010 Aug;34(8):1122-31. PMID: #20588177#