Abstract

We report on a case of angiomatoid fibrous histiocytoma located deep in subcutaneous tissue of the left shoulder in an 11-year-old boy. An ovoid firm mass was slowly increasing in size for 5 months without any pain or tenderness. The tumor was grossly multicystic, with dense fibrous capsule and it measured 7.5 x 7.5 x 4.0 cm. The locules contained hemorrhagic fluid, and the inner surface was purplish brown and trabecular. The septal solid areas were cellular, and they consisted of histiocytoid spindle cells that were arranged in a storiform or fascicular pattern. The tumor cells showed immuno-positivity for CD99, CD68 and desmin. These findings were compatible with angiomatoid fibrous histiocytoma of an uncommon location.

• Keywords: Angiomatoid fibrous histiocytoma;Shoulder;