A 35 year old female presented with a painless swelling on the outer aspect of left upper arm for the last one year. On examination, the swelling measured 4.5 x 4 cm. It was soft to firm, ill defined, non-tender, deeply located and was not attached to the overlying skin. A computed tomographic scan revealed a homogenous soft tissue mass measuring 4.5 x 4 cm located within the muscle.

Keywords: Alveolar soft part sarcoma; TFE3; fine needle aspiration cytology.