Benign fibrous histiocytoma: a rare finding on bone scan staging for prostate adenocarcinoma

Benign fibrous histiocytoma is a rare bone tumor that usually presents with localized pain and/or a pathological fracture. We report on a patient with adenocarcinoma of the prostate who had a radionuclide bone scan for staging, which was suspicious for metastatic disease. Histologic examination of left eleventh rib revealed a Benign Fibrous Histiocytoma (BFH). To our knowledge, this is the first BFH found solely on bone scan.