Large complex cystic soft tissue mass involving the posterior medial aspect of the leg. The lesion demonstrates mixed high and intermediate signal intensity on T2 and a central haemorrhagic component of high T1 images. Intralesional fluid-fluid levels are seen giving the appearance of "bowl of grapes". The mass is located at the expected location of pes anserinus bursa. There is no bony or joint extension.
The differential diagnosis would include synovial sarcoma or angiomatoid fibrous histiocytoma (pleomorphic undifferentiated sarcoma).