Osteoblastoma in the nasal cavity: F-18 FDG PET/CT and Tc-99m MDP 3-phase bone scan findings with pathologic correlation.

A benign osteoblastoma of the nasal cavity is very rare. A 57-year-old woman, who had a radical hysterectomy for carcinoma of the uterine cervix 5 years ago, underwent F-18 FDG PET/CT. An expansile bone tumor with high glucose metabolism in the middle turbinate of the left nasal cavity was incidentally demonstrated. A subsequent Tc-99m methylene diphosphonate 3-phase bone scan revealed focal increased uptake of radionuclide in all 3 phases at the corresponding tumor. Histology confirmed a benign osteoblastoma that was composed of proliferating osteoblasts with woven bone spicules and rich vascular stroma. Scintigraphic findings, including F-18 FDG PET/CT and 3-phase bone scan, reflected the pathologic features well.