Figure 4c. Deep intramuscular lipoma with thick septa in a 60-year-old woman with a slowly enlarging mass in the thigh. (a, b) Coronal T1-weighted (600/30) (a) and T2-weighted (2000/90) (b) MR images show a heterogeneous mass (*) that is predominantly isointense relative to subcutaneous fat. However, prominent thick septations with some nodularity are also present (arrowheads), some of which reveal high signal intensity on the long TR image (b). These features do not allow distinction from well-differentiated liposarcoma. (c) Photograph of the longitudinally sectioned gross specimen demonstrates the lipomatous tissue (*) with thick septa and focal nodularity (arrows).