Benign fibrous histocytoma is a well-established soft tissue neoplasm, and the occurrence of this lesion in the oral cavity is rare. Only 3 cases of this lesion arising centrally in the mandible have been reported in the literature. In this paper, we reported a patient with benign fibrous histiocytoma of the mandible.
A 42-year-old Japanese woman was referred to our department complaining of swelling on the lingual side of the right mandibular body in November 1987. Radiographic examination demonstrated a illdefined radiolucent lesion in the right body of the mandible extending from 7 to the ramus. We performed segmental resection of the mandible in March 1988. A solid yellowish lesion was observed in the mandible body, and partial destruction of the lingual palate was found. Histopathologically, the lesion was composed of spindle-shaped figroblastic cells and histiocytic cells. The histiocytic cells showed negative staining for S-100 protein and positive staining for a-1 antitrypsin. Based on these clinical and histopathological findings, the lesion was diagnosed as benign fibrous histiocytoma. The postoperative course was good and no signs of recurrence have been seen almost 6 years and 4 months after operation.