[MRI of suspected bone and soft tissue sarcomas - an overview]

Sarcomas are rare malignant tumors of connective and supportive tissues, associated with relatively poor five-year survival. According to Swedish patient care bundles ("standardiserat vårdförlopp"), MRI should be performed at local radiology departments before a possible referral to a sarcoma center when there is a strong suspicion of a soft tissue sarcoma, highlighting the need for adequate knowledge of appopriate MRI protocols. For soft tissue lesions, MRI is diagnostic only for a few entities, such as simple lipomas. Most muskuloskeletal tumors, however, require biopsy for definitive diagnosis. Consequently, MRI is primarily used to assess tumor extent prior to biopsy and potential surgery. The Swedish Society of Musculoskeletal Radiology (SFMSR) recommends that an MRI protocol for musculoskeletal tumors should always consist of at least the following three sequences: coronal STIR FSE, axial T1-weighted FSE, and axial T2-weighted FSE. Coronal STIR is mainly used for tumor detection and evaluation of lipomatous lesions. Axial T1 is primarily used to assess intraosseous tumor extent and characterize lipomatous lesions. Axial T2 is primarily used to evaluate soft tissue tumor extension and extraosseous components of bone tumors.