This is the external surface of a liposarcoma, a malignant tumor of adipocyte origin. Note the irregular surface and color, with relatively few areas of the yellow color typical of fat. Tumor of adult life, with a peak incidence between 40 and 60 years of age.
Retroperitoneal tumors occur somewhat more frequently in women.
There is no evidence that any race or geographical area is more prone to develop liposarcomas. The three most common locations are the thigh, the retroperitoneum, and the inguinal region. Liposarcomas typically manifest a lobulated appearance. Cut section may reveal a mucinous appearance, especially if the myxoid component is prominent. Typically, at least some evidence of yellow color, due to the lipid material, is present.