Type:
Educational Exhibit
Keywords:
Musculoskeletal soft tissue, Oncology, MR, Imaging sequences, Neoplasia
Authors:
K. Motupally, K. Singh, P. Jeremic
DOI:
10.26044/ranzcr2022/R-0232
Imaging findings OR Procedure details
The use of imaging in desmoid tumours can define the extension and potential for surgical excision of the lesion. MRI is the preferred modality for interval imaging for axillary musculoskeletal fibromatosis [9].
T1-weighted images of desmoid tumours are commonly hypointense (due to high cellullarity) or isointense to muscle whereas on T2-weighted images they are hyperintense. The use of gadolinium contrast shows moderate enhancement with hypointense bands due to collagen bundles which can increase the specificity of the diagnosis [10]. The mean ADC of desmoid tumours on DWI imaging is generally higher than soft tissue tumours which can be useful in differentiating between these differentials [11]. Common findings include an intermuscular location with a rim of fat surrounding the lesion (split-fat sign), linear extension along fascial planes (fascial tail sign) resembling a flame (flame sign). Desmoid tumours can have well defined borders but may also have infiltrative margins to nearby structures involving adjacent compartments, bone invasion and encasing adjacent neurovascular bundles such as the brachial plexus [12].