Parosteal osteosarcoma of the 2nd metatarsal.

While masses of the foot are relatively common, bone forming lesions of the foot are less common. The differential diagnosis includes benign and malignant lesions. A thorough history and physical examination, along with selective imaging, can guide the practitioner to an accurate diagnosis. For malignant lesions, appropriate local and whole body imaging consistent with published national guidelines in order to stage the patient's disease helps to guide treatment. Knowledge of the national history of the lesion will guide decision making for appropriate surgical resection and the need for any adjuvant therapy. Postresection surveillance of malignant or locally aggressive lesions is also important in the patient's postoperative care. We present a case of parosteal osteosarcoma of the 2nd metatarsal.