Specimen is an aggregate of brown papillary tissue which on cut section has a lobulated appearance.
Histologically this was found to be a benign tumour composed of histiocytes and numerous giant
cells. The brown colouration is due to the deposition of hemosiderin pigment.
This 27-year-old male presented with a four year history of left ankle pain. On
examination swelling was noted immediately adjacent to the left lateral malleolus. The tumour
was surgically removed and has not recurred.