Use of Mitotic Activity and the Size of Any Dedifferentiated Component for Risk Assessment in MDM2-Amplified Liposarcoma

The characteristic molecular signature for both atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma is amplified sequences derived from chromosome 12q13-15, including MDM2 proto-oncogene (MDM2). As the progression of atypical lipomatous tumor/well-differentiated liposarcoma to the more aggressive dedifferentiated liposarcoma has the potential to adversely affect patient outcomes, the extent of the latter component might be important to evaluate.