Presentation
Painless swelling over lateral ankle in an active sportswoman. No deterioration in performance.
Patient Data
Note: This case has been tagged as "legacy" as it no longer meets image preparation and/or other case publication guidelines.
Dense, well-defined, sausage-shaped soft tissue mass sitting on the postero-lateral aspect of the ankle paralleling the peroneal tendons. The density is due to the presence of hemosiderin.
Large, lobulated and enhancing soft tissue mass within the peroneal tendon sheath displacing the tendons. Key to the diagnosis is presence of magnetic susceptibility on the gradient echo sequence i.e. hemosiderin. No bone erosion at this time.
Case Discussion
Giant cell tumor of the tendon sheath are benign tumors equivalent to pigmented villonodular synovitis, hence the presence of hemosiderin. They are more commonly seen in hand tendons.