What is CDC73-associated (hyperparathyroid-jaw) syndrome?
CDC73-associated (hyperparathyroid-jaw) syndrome (HPT-JT) is a rare disease caused by mutations – or genetic changes – in the CDC73 gene (also HRPT-2). Those affected have a much higher risk of parathyroid tumors and also parathyroid hyperfunction (primary hyperparathyroidism, PHPT), bone tumors (ossifying fibromas) in the upper and lower jaw, and tumors of the kidneys and uterus.
How is CDC73-associated (hyperparathyroid-jaw) syndrome diagnosed?
Clinical Diagnostic Criteria
Confirming the Diagnosis
The clinical diagnosis is made through blood tests (measuring calcium and parathormone) and imaging diagnostics (X-ray of the jaw, ultrasound of the kidneys and pelvis).
Genetic Diagnostics
The diagnosis of “HPT-JT” is confirmed by detection of a mutation – or genetic change – in the CDC73 gene.
What is the risk of cancer?
Primary Hyperparathyroidism
Tumors in the Jaw
Disease of the Kidneys
Tumors in the Uterus
What causes CDC73-associated (hyperparathyroid-jaw) syndrome?
CDC73-associated (hyperparathyroid-jaw) syndrome is brought about by a mutation – or genetic change – in the CDC73 gene. This gene encodes for the protein parafibromin, which plays a role in the reproduction of genetic material. Now if the CDC73 gene is in an altered form, the protein parafibromin can no longer function properly, resulting in the development of a tumor.
It is not yet known how frequently HPT-JT syndrome occurs. What is known is that the disease can be passed on to children from their parents. In these cases, it is inherited as an autosomal dominant disease.
Is there a treatment?
Primary Hyperparathyroidism
Since it is usually the case that there is only one parathyroid tumor causing the PHPT, a minimally invasive approach for removing the parathyroid tumor is preferred, which involves the following:
If malignant parathyroid cancer is present, the parathyroids and the thyroid lobe on the same side should be removed.
Tumors in the Jaw
If possible, the tumor should be removed completely. There are no known medicinal approaches to date for tumors that have not been fully removed. Due to the risk of relapse, patients should undergo aftercare checkups.
Disease of the Kidneys
With cystic diseases, it is necessary to lay out individual treatment depending on their extent and manifestation. There are no specific guidelines for HPT-JT patients.
Tumors in the Uterus
With tumors of the uterus, it is necessary to lay out individual treatment depending on their extent and manifestation. There are no specific guidelines for HPT-JT patients.
Surveillance Recommendations for the Early Detection of Cancer
Surveillance Recommendations
There are no standard surveillance recommendations for patients with a CDC73 mutation to date. Based on the literature currently available, the following is recommended:
Self-Care and Support
What should I pay special attention to?
Hyperparathyroidism may present as bone pain. In addition, kidney or gall stones may occur and cause pain in the flanks and/or upper abdomen regions. Kidney cysts can trigger pain in the area of the flanks, and urine anomalies or urinary tract infections may occur as well. Tumors in the uterus usually present themselves through bleeding or changes in menstruation. Tumors in the jaw may prevent the eruption of teeth in the jaw and cause swelling and pain.
Should you notice one of the symptoms or other complaints or anomalies listed above, be sure to see a doctor right away.
Support Groups and Additional Information
Unfortunately, we are as yet unaware of any existing support groups for patients with a CDC73-associated (hyperparathyroid-jaw tumor) syndrome. We will add new information as it becomes available.