FDG-PET/CT in staging of clear cell odontogenic carcinoma.

Clear cell odontogenic carcinoma (CCOC) is a rare neoplasm; only 75 cases have been reported in the English language literature. They have a tendency for recurrence and a capacity to metastasize. There is very little known regarding the metabolic features of this tumour or the utility of fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scans in the staging and follow-up of these tumours. We present two cases of CCOC with their relevant FDG-PET/CT scan findings. The first patient had primary CCOC of the mandible that was FDG-avid, and the other had recurrence of CCOC of the anterior mandible and superomedial orbit that was not FDG-avid. FDG uptake in CCOC appears to be variable. Although FDG-PET/CT is useful in other head and neck cancers and has benefits compared to other imaging modalities, further studies are needed to investigate the sensitivity of FDG-PET/CT in CCOC.