Detection of local recurrent disease in musculoskeletal tumors: magnetic resonance imaging versus computed tomography.

A 2 1/2-year prospective study of surgically treated malignant mesenchymal neoplasms showed magnetic resonance imaging (MRI) to be superior to computed tomography (CT) in sensitivity for local recurrent disease measuring less than 15 cm3. Larger masses were detected with similar sensitivity; specificity and predictive values did not differ. The presence of areas of high signal intensity on T2-weighted images proved to be a reliable criterion except in fibrous neoplasms. However, differentiation between non-hemorrhagic fluid collections, cross-sectioned veins or bowel contents and small tumor nodules cannot be made simply by signal intensity, but has to be based upon the evaluation of gross morphologic criteria.