Extraskeletal osteosarcoma of the jaw.

Extraskeletal osteosarcoma is a rare malignancy, which accounts for 1-2% of all soft tissue sarcomas; occurrence of these tumors in the head and neck is extremely rare. We present a case of extraskeletal osteosarcoma arising in the subcutaneous tissue of the jaw angle, the central portion of which displayed calcification. Imaging findings were interesting in terms of a high grade malignancy in that the tumor was small and well circumscribed; its appearance mimicked a calcified lymph node. The differential diagnosis of this lesion as well as the imaging and pathological features of extraskeletal osteosarcoma are discussed.