Recurrent hyperparathyroidism and a novel nonsense mutation in a patient with hyperparathyriodism-jaw tumor syndrome.

OBJECTIVE: To present the case of a hyperparathyroidism-jaw tumor (HPT-JT) patient with a novel nonsense mutation of the CDC73 gene. METHODS: We present the case of a patient with a history of three prior maxillectomies and two prior parathyroidectomies who presented with recurrent primary hyperparathyroidism (PHPT). We also briefly review the literature pertaining to HPT-JT. RESULTS: Genetic analysis revealed a novel nonsense mutation (c.85G>T; pGlu29) in exon 1 of CDC73. The patient's son underwent genetic testing for a CDC73 mutation and was found to be negative. CONCLUSION: HPT-JT is a rare condition characterized by PHPT and benign tumors of the mandible and maxilla. Up to 15% of HPT-JT patients with PHPT have parathyroid carcinoma. HPT-JT is associated with an inactivating mutation of CDC73, a gene that codes for the tumor suppressor protein parafibromin. This report expands our understanding of the genetics underlying this rare disorder and emphasizes the importance of early detection in order to prevent hypercalcemic complications such as parathyroid carcinoma.