Case 289.

History An 8-year-old girl presented to our hospital with painful swelling of the left thigh and soft-tissue swelling in the right chest wall. The patient's history revealed that the swelling had been present since birth but had grown slowly. She had no history of relevant trauma. Her blood pressure was 145/95 mmHg (normal value, <115/76 mmHg), and her heart rate was 105 beats per minute (normal value, 75-118 beats per minute). The patient's electrocardiogram displayed sinus tachycardia. Physical examination revealed soft-tissue hypertrophy in the left thigh and right lower chest wall. A painful soft and flexible mass measuring approximately 5 × 6 × 15 cm (in the anteroposterior, transverse, and craniocaudal directions, respectively) was detected at the left thigh. Moreover, a painless soft mass measuring approximately 3 × 8 × 10 cm (in the anteroposterior, transverse, and craniocaudal directions, respectively) was detected in the right lower chest wall, and the overlying skin was intact. Pink macules with a 3-cm diameter on the anterior left superior thigh and a 2.5-cm diameter in the left inguinal region were detected. Examination of other systems, including the cardiovascular system, revealed normal findings. Laboratory test results were within normal limits. Abdominal US showed perirenal vascular collaterals, and musculoskeletal US of the left thigh revealed vascular collaterals (images not shown). Therefore, thoracoabdominal CT angiography (Fig 1a-1c) and contrast material-enhanced MRI of the bilateral thigh (Fig 2a-2c) were performed.