Osteoblastic Osteosarcoma of the Mandible: Findings on Tc-99m HMDP Bone and Ga-67 Citrate Scintigraphy

A 25-year-old woman presented with a disturbance in the opening of her mouth 5 months before admission. On admission, painful swelling of the right preauricular region was revealed. Computed tomography (CT) demonstrated a soft tissue density mass around the right condylar process of the mandible. Tc-99m hydroxymethylene diphosphonate (HMDP) bone scintigraphy and Ga-67 citrate scintigraphy showed avid uptake in the mass. The tumor was histologically identified as an osteoblastic osteosarcoma of the right mandible. There are few reports of Ga-67 citrate scintigraphy findings of osteoblastic osteosarcoma of the mandible. The accumulation patterns on Tc-99m HMDP bone scintigraphy and Ga-67 citrate scintigraphy are possibly characteristic of osteoblastic osteosarcoma of the mandible.