Ossifying fibromyxoid tumor of soft parts presenting as a scalp cyst

Background: Ossifying fibromyxoid tumor of soft parts (OFMT) is a rare mesenchymal neoplasm of intermediate malignant potential. The tumor most commonly occurs on the extremities with a male predominance. We present an unusual case of OFMT occurring as a cystic lesion on the scalp of a female. Case history: A 67-year-old woman presented with a 6-year history of a well demarcated cystic scalp mass. Physical examination revealed a slightly movable, multilobular mass of the left parietal scalp which was subsequently excised. Histological evaluation revealed an OFMT comprised of bland, small cells and a thick collagenous capsule containing an incomplete rim of lamellar bone. Conclusion: OFMT is an unusual tumor which can usually be considered as having an intermediate risk of malignancy. It generally occurs in the extremities with a male predominance. The clinical differential for a cystic mass on the scalp is broadened by this unusual case of an OFMT.