Presentation
Painless swelling of the posterior aspect of the left mid-thigh.
Patient Data
Relatively well-defined intramuscular soft tissue mass of the mid-thigh centered on the distal portion of the adductor magnus muscle and extending to the vastus medialis and intermedius through the femoral intermuscular septum with displacement of the sciatic nerve. It appears isointense to muscles on T1, hyperintense on T2 and stirs with restricted diffusion and vivid heterogeneous enhancement on postcontrast sequences. Normal thickness and signal intensity of the adjacent femoral cortex.
Case Discussion
MRI features of an enhancing intramuscular soft tissue mass centered on the adductor magnus muscle extending through the femoral intermuscular septum to the vastus medialis and intermedius muscles.
The patient went on to have surgical resection of the tumor with a histopathological exam that confirmed the diagnosis of Ewing sarcoma/primitive neuroectodermal tumor (PNET).