Parosteal osteogenic sarcoma of the mastoid bone.

Parosteal osteogenic sarcoma (POS) is an uncommon surface bone tumor, most often arising from the metaphyseal end of long bones. Involvement of the cranial bones is rare, with only 1 case of mastoid bone POS previously reported in the literature. Two patients with POS of the mastoid are presented, 1 followed up for 25 years after surgical treatment. The… (More)