Soft tissue masses in the foot and ankle: characteristics on MR Imaging

Benign neoplasms and tumor-like lesions constitute the majority of soft tissue masses in the foot and ankle. Therefore, malignant tumors are often unsuspected at this site and misdiagnosed clinically, especially if occurring in young individuals with unspecific or long-standing clinical symptoms. In addition to radiography, MR imaging represents the method of choice in evaluation of foot tumors. Because of their relatively characteristic imaging appearance, in most cases of benign soft tissue lesions of the foot and ankle a specific diagnosis can be suggested. Unfortunately, malignant tumors can also arise with nonaggressive imaging features. Diagnostic errors can be avoided if any soft tissue lesion that cannot be specifically diagnosed is regarded as potentially malignant until proved otherwise. This article reviews the MR appearance of the most common benign and malignant soft tissue masses in the foot and ankle together with their clinical, radiographic, and pathological findings.