Chondromyxoid fibroma occurs primarily in the long tubular bones of the lower extremity, with the foot representing the second most frequent location after the knee. This benign cartilaginous tumor of bone is currently the rarest reported neoplasm of cartilaginous origin. This mass can mimic other benign and malignant bone tumors owing to its variable histologic features. We report 2 cases of chondromyxoid fibroma of the calcaneus with varying presentations. Initially, advanced imaging studies pointed to a diagnosis of a unicameral bone cyst. Pathologic examination is difficult but can be used to differentiate this lesion from more serious conditions. A quick and accurate diagnosis of chondromyxoid fibroma can prevent unnecessary treatment that could be harmful to the patient.
Level of Clinical Evidence: 4