Fig. 1.

A 14-year-old female patient presented with a chief complaint of growing palpable mass in the anterior aspect of the left mid thigh. (A) On the plain radiography of the left femur, soft tissue shadow was seen in the anterior aspect of the midshaft of the femur. (B) On T2-weighted coronal magnetic resonance image, there was a 7 × 5 × 3 mm-sized, well-enhanced soft tissue mass at the same site. (C,D) On computed tomography angiogram, a highly vascularized mass lesion was observed, and tortuous prominent blood vessels were seen on superior and inferior margins of the mass. (E,F) There was no metastasis seen on positron emission tomography computed tomography. (G) Incisional biopsy was performed and the mass was diagnosed as alveolar soft part sarcoma. A wide marginal excision was performed.