[18F]Fluorocholine PET/CT in a 15-year-old patient suggested HPT-JT syndrome with active cemento-ossifying fibroma

Background: Hyperparathyroidism-jaw tumor (HPT-JT) syndrome is a rare autosomal dominant disorder caused by CDC73 gene mutations, predisposing individuals to primary hyperparathyroidism (pHPT), cemento-ossifying fibromas, and other neoplastic conditions. [18F]Fluorocholine PET/CT has emerged as a tool for localizing hyperfunctioning parathyroid glands in pHPT, but its application in HPT-JT syndrome remains unreported. Case presentation: We describe the case of a 15-year-old male presenting with severe hypercalcemia, increased PTH serum levels, and a history of cemento-ossifying fibroma removal. Standard imaging, including [99mTc]Tc-MIBI scintigraphy, was inconclusive. [18F]Fluorocholine PET/CT successfully identified a hyperfunctioning parathyroid gland, identified as parathyroid atypical adenoma at subsequent histology, and a recurrent maxillary cemento-ossifying fibroma. Genetic testing confirmed a CDC73 mutation, leading to the diagnosis of HPT-JT syndrome. Conclusions: To our knowledge, this is the first reported case utilizing [18F]Fluorocholine PET/CT for the evaluation and management of HPT-JT syndrome with active presence of a maxillary cemento-ossifying fibroma. Given its superior sensitivity compared to conventional imaging, [18F]Fluorocholine PET/CT provided critical information for surgical planning and it might be a useful diagnostic tool for long-term disease monitoring. This case highlights the potential role of [18F]Fluorocholine PET/CT in detecting both parathyroid and jaw manifestations of HPT-JT syndrome, emphasizing the need for further research into its application in hereditary endocrine disorders.