Sonographic imaging of abdominal and extraabdominal desmoids.

PURPOSE: To describe the sonographic imaging characteristics of abdominal and extraabdominal desmoids. MATERIALS AND METHODS: We retrospectively investigated 12 histologically and pathologically proven abdominal and extraabdominal desmoids. Two radiologists with musculoskeletal sonography experience reviewed sonographic images for lesion location, size, echotexture, and vascularity with agreement by consensus. RESULTS: Desmoids were seen in 9 females and 3 males. They manifested as slowly growing masses. Nine lesions were intramuscular and 3 were found within the subcutaneous adipose tissue. A typical sonographic feature of all intramuscular desmoids was the spindle-shaped margin at the tumor ends when scanned along the long axis of the affected muscle. The desmoids arising from the fascia had an irregular shape. Tumor vascularity was rich in 6 cases and poor in 6 cases. A fibrillar pattern within the tumor was found in 75% of the cases. CONCLUSION: A spindle-shaped appearance is common in intramuscular desmoids. Hyperechoic areas and a fibrillar pattern within desmoids are also common sonographic features.