Presentation
Slowly growing swelling over the dorsum of foot.
Patient Data
Soft tissue swelling at dorsum of foot. No calcifications or bony erosion.
A variegated hyperintense heterogeneous soft tissue lesion at the dorsum of the foot underneath and lifting the extensor digitorum longus tendons 2nd, 3rd, 4th slips. A tendon is seen to pass through the lesion which represents extensor digitorum brevis tendon slip. Intraarticular extent is seen at cuboid-4th metatarsal articulation.
No intraosseous extension, no calcification.
The doppler study demonstrates internal vascularity. Intraarticular extension is also well delineated.
Case Discussion
MRI reveals a heterogeneous soft tissue lesion closely associated with the extensor digitorum longus involving the brevis tendons, with dark intralesional signals on GRE: these findings represent giant cell tumor of the tendon sheath (GCTTS), also known as pigmented villonodular tumor of the tendon sheath (PVNTS).
Excision biopsy was performed and the diagnosis confirmed on histopathology.