Background: A 51-year-old previously healthy woman presented with a perianal mass. The mass has been there for some years and has gradually increased in size ever since with progressive pain when she sits. There was no history of trauma nor injections in this region.
Clinically, the mass was not tender and rather soft, with superficially some focal harder spots. A large lipoma was suspected on clinical basis.
An ultrasonography and subsequent MRI scan, including sequences following administration of gadolinium contrast medium were performed.