Fibrous dysplasia が悪性転化した節骨洞原発 low-grade central osteosarcoma (LGCOS) 症例

抄録

We report the clinical manifestation of a rare case of low-grade central osteosarcoma (LGCOS) originating in the right ethmoid sinus.
A 64-year-old woman consulted our hospital with a chief complain of left nasal obstruction. CT showed osteosclerosis in left ethmoid sinus, which was considerd as benign tumor. We performed tumor resection, and the diagnosis was fibrous dysplasia. One year later, osseous swelling of the root of nose was found and CT revealed recurrent osteosclerosis in the left ethmoid sinus, which extend left nasal cavity and left ethmoid sinus. We performed tumor resection again, and the diagnosis was low-grade central osteosarcoma (LGCOS). We considered that fibrous dysplasia changed into LGCOS.
LGCOS are associated with a good prognosis. The pathological diagnosis of LGCOS from fibrous dysplasia is difficult. To diagnosis of LGCOS, it is necessary to confirm whole is low grade.