Radiologic evaluation of soft-tissue masses: A current perspective

MR imaging is the preferred modality for the evaluation of a soft-tissue mass after radiography. The radiologic appearance of certain soft-tissue tumors or tumorlike processes, such as myositis ossificans, fatty tumors, hemangiomas, peripheral nerve sheath tumors, pigmented villonodular synovitis, and certain hematomas may be sufficiently unique to allow a strong presumptive radiologic diagnosis. It must be emphasized that MR imaging cannot reliably distinguish between benign and malignant lesions and when radiologic evaluation is nonspecific, one is ill-advised to suggest that a lesion is benign or malignant solely on its MR imaging appearance. When a specific diagnosis is not possible, knowledge of tumor prevalence by location and age, with appropriate clinical history and radiologic features, can be used to establish a suitably ordered differential diagnosis.