recurrence of hyperparathyroid hypercalcemia in a patient with the hrpt-2 mutation and a previous parathyroid carcinoma in hyperparathyroidism-jaw tumor syndrome

conclusions the recurrence of hyperparathyroid hypercalcemia in htp-jt syndrome after an initial total parathyroidectomy is a well-known condition necessitating careful management, an evaluation of any underlying genetic abnormality, and a family examination. a surgical treatment and surveillance of calcium and pth measurements are necessary to prevent a recurrence. introduction cancer in the parathyroid gland is rare, but parathyroid cancer is occasionally seen in relation to genetic abnormalities. due to a limited amount of evidence, the optimal handling of these cases is not clear. furthermore, the presence of a malignant parathyroid tumor is rarely known at the time of the initial operation; therefore, re-operations are often necessary. the aim of this study was to present the case of a patient with a previously diagnosed jaw tumor and parathyroid carcinoma that presents as a recurrence of hyperparathyroid hypercalcemia. case presentation a 41-year-old patient who was already diagnosed with a parathyroid carcinoma and a jaw tumor caused by a cdc73 mutation, presented with biochemical evidence of increasing parathyroid hormone (pth) and calcium levels after a previous total parathyroidectomy. the patient’s ionized calcium increased to 1.55 mmol/l and pth increased to 16.0 pmol/l. a previous genetic analysis revealed a mutation in the cdc73 gene. there was no family history of hyperparathyroidism. we performed a sestamibi scintigraphy and an 11-c methionine (met) positron emission tomography (pet) scan that showed a recurrence on the left side of the trachea. the patient underwent a third neck operation for the removal of a tumor on the left side of the trachea. the pathology report revealed that the tumor was a lymph node metastasis from the previous parathyroid carcinoma. the patient is currently enrolled in our follow-up regime. hyperparathyroidism-jaw tumor (hpt-jt) syndrome is a rare autosomal dominant disorder characterized by a parathyroid adenoma or carcinoma, fibro-osseous lesions (ossifying fibroma) of the mandible and maxilla, and renal cysts and tumors. this autosomal dominant familial cancer syndrome has been reported with a variable and incomplete penetrance, and up to 10% of gene carriers do not show any clinical manifestations. here we present a patient’s case and discuss the literature related to this condition.