Pitfalls in MR imaging of musculoskeletal tumors.

A wide range of musculoskeletal tumors and tumor-like conditions may be encountered when patients undergo radiologic examinations. Although MR imaging is a powerful medical imaging method that has been used extensively in the evaluation of musculoskeletal tumors, nontumoral or tumorlike lesions may have similar imaging findings. The imaging features of certain normal, reactive, benign neoplastic, inflammatory, traumatic, or degenerative processes in the musculoskeletal system may mimic malignant tumors. Misinterpretation of the imaging findings can lead to inappropriate clinical management of the patient. We review and describe the MR imaging characteristics of nontumoral bone lesions that are located in the marrow cavity, cortical bone, or in both, and soft tissue lesions that may be misinterpreted as sarcoma.