Liposarcoma is the most common soft tissue malignancy in adults accounting for at least 20% of all sarcomas in this age group. Liposarcoma is a lipogenic tumour subclassified into four main histologic groups, including well-differentiated liposarcoma (lipoma-like and sclerosing types), myxoid-round cell liposarcoma, pleomorphic liposarcoma, and dedifferentiated liposarcoma. The histologic group is predictive of both the clinical course of the disease and the ultimate prognosis.

Myxoid-round cell liposarcoma is a subtype of liposarcoma characterized by the presence of the reciprocal chromosomal translocation t(12;16)(q13;p11). This translocation creates the FUS-DDIT3 chimeric gene.

The DDIT3 gene encodes a member of the CCAAT/enhancer-binding protein (C/EBP) family of transcription factors. The protein functions as a dominant-negative inhibitor by forming heterodimers with other C/EBP members, such as C/EBP and LAP (liver activator protein), and preventing their DNA binding activity. The protein is implicated in adipogenesis and erythropoiesis, is activated by endoplasmic reticulum stress, and promotes apoptosis.