Hyperparathyroidism–Jaw Tumor Syndrome: A Case Study and Review of This Rare Condition

encodes parafibromin, a ubiquitously expressed nuclear protein with antiproliferative action.Overall, >100 germline and somatic alterations of CDC73 have been identified.The CDC73 mutation is primarily associated with HPT-JT, familial isolated hyperparathyroidism, and sporadic parathyroid cancer.5 IntroductIonPrimary hyperparathyroidism (PHPT) is a common endocrine disorder that imposes a substantial health burden.While the majority of PHPT cases are sporadic, an underlying hereditary condition is identified in up to 10% of patients.Clinical heterogeneity and the absence of a family history may result in the underrecognition of inherited cases, leading to an underestimation of the true prevalence.Familial forms of PHPT encompass a genetically and clinically diverse group of disorders, including multiple endocrine neoplasia (MEN) types 1, 2A, and 4, hyperparathyroidism-jaw tumor (HPT-JT) syndrome, nonsyndromic familial isolated hyperparathyroidism, neonatal severe PHPT, autosomal dominant moderate hyperparathyroidism, and familial hypocalciuric hypercalcemia.In recent decades, a growing number of genetic mutations responsible for hereditary PHPT have been identified.The diagnosis of hereditary PHPT requires a high index of suspicion, with key diagnostic principles involving the recognition of distinctive clinical features, obtaining a detailed family history, and making timely referrals for genetic testing.1,2 Hyperparathyroidism-jaw tumor is a rare familial cause of PHPT first described in 1990.3 In 2019, Torresan and Iacobone reported 154 families with HPT-JT which included 365 patients with PHPT. 4 Since then, there have been a few more reports of single patients and families with HPT-JT.It is an autosomal dominant inherited condition caused by a pathogenic mutation in the Cell division cycle 73 (CDC73) tumor suppressor gene (previously known as the HRPT2 gene).This gene