Parathyroid hormone (PTH) regulates calcium, phosphorus, and magnesium levels within the blood and bone. The four parathyroid glands, which are located in the neck around the thyroid, secrete this hormone to control the blood level of calcium. When calcium in the blood stream is low, more PTH is secreted – this signals your body to absorb more calcium from your gut, excrete less calcium from the kidneys, and release calcium stores from bones.
Hyperparathyroidism occurs when there is an enlargement or tumor of one or more of the parathyroid glands, which results in overproduction of PTH. There are three main types of hyperparathyroidism:
- Primary: One or more of the parathyroid glands independently over-produces PTH and raises the calcium level above normal.
- Secondary: The parathyroid glands over-produce PTH in response to chronically low calcium levels in the blood. This can occur in patients with kidney failure, vitamin D deficiency, and diseases causing malabsorption of calcium from the gut.
- Tertiary: The parathyroid glands independently over-produce PTH in patients with secondary hyperparathyroidism from kidney failure who then undergo kidney transplantation. In these patients, the transplanted kidney normalizes calcium levels in the blood, but the parathyroid glands continue to over-produce PTH because they have been stimulated to do so for a long time.
There is a wide range of disease severity in hyperparathyroidism – patients with more severe disease may experience kidney stones, bone pain, fractures, and marked neurocognitive disturbances. On the other hand, patients with mild disease may have more subtle symptoms that are difficult to attribute directly to hyperparathyroidism, such as fatigue, muscle weakness, irritability, memory loss, constipation, excessive urination, or heartburn. Prolonged hyperparathyroidism can lead to significant health problems such as osteoporosis, cardiovascular disease, stroke, and kidney damage.
At Weill Cornell Medicine, we use a multidisciplinary approach to accurately diagnose hyperparathyroidism with comprehensive biochemical tests including blood and urine evaluations. If the diagnosis is confirmed then imaging studies – including neck ultrasound, CT scan, and Sestamibi scan – are utilized to help guide the surgical treatment.
For primary hyperparathyroidism, surgery to remove the affected gland(s) is offered to patients with severe disease and symptoms that are directly attributable to hyperparathyroidism. However, the decision to offer surgery for patients with subtle symptoms, or without symptoms, is more complex. Since about 25% of patients with mild disease will eventually progress to have more severe disease, we offer surgery to patients with the following factors who may be at risk to develop worsening disease:
• Age < 50
• Calcium level >1mg/dL above the upper limit of normal range
• Elevated calcium in the urine
• Reduced kidney function
In addition, if subtle symptoms can not be explained by other factors, patients can choose to proceed with surgery.
For secondary hyperparathyroidism, many patients can initially be managed with medications in conjunction with a transplant nephrologist. Surgery can be considered in patients with severe disease who do not respond well to medical management or who cannot tolerate the medical regimen.
For tertiary hyperparathyroidism, patients with mild disease can be medically managed; however, those with worsening disease, notable symptoms, or severe electrolyte derangements that do not improve with medications are candidates for surgery.
Surgery for hyperparathyroidism has been associated with improved bone mineral density (correcting or improving osteoporosis), better kidney function, and reduced long-term cardiovascular risk. Additionally, several studies have suggested that neuro-cognitive symptoms may resolve after surgery, thus also improving quality of life. Your endocrine surgeon will discuss if surgery is the right option for you.
Our goal is to cure primary hyperparathyroidism using a minimally invasive surgical approach to remove the diseased parathyroid gland or glands. The operation can be performed under local or general anesthesia through a small incision in your neck using intraoperative PTH monitoring. Typically all 4 glands are visualized during the surgery. Since parathyroid hormone in the bloodstream degrades within minutes on its own, we also measure the level at the beginning of surgery and then again 10 minutes after the affected parathyroid gland(s) have been removed. This is a second way to confirm that a successful operation has been performed.
In secondary and tertiary hyperparathyroidism, all 4 parathyroid glands are usually affected, and thus patients require a multi-gland exploration to ensure that no diseased parathyroid glands are left behind. Our typical approach is to excise 3.5 glands, while leaving a 0.5 gland remnant to ensure normal PTH and calcium levels after surgery.
The risks of parathyroid surgery include bleeding, nerve injury that could affect your vocal cords and thus the quality of your voice, and damage to the remaining parathyroid glands resulting in low calcium levels in the bloodstream. Our surgeons, due to their expertise and large experience, have minimized these risks to some of the lowest in the country. Though the incidence of voice complications is exceedingly low in our hands, if necessary, we can evaluate your vocal cords before and after surgery to assess for any laryngeal dysfunction using flexible laryngoscopy. Additionally, during the parathyroid operation itself, our surgeons may use nerve-monitoring technology, which helps assess the integrity of your vocal cord nerve in real-time.
After parathyroid surgery, most patients will be able to go home the same day after a 4-6 hour observation period. Patients with secondary and tertiary hyperparathyroidism may need to stay in the hospital a few days for close calcium level observation. Regardless, recovery is quick and the procedure causes little discomfort. Patients usually resume normal activity within a couple days and some patients return to work within a few days of surgery. Your surgeon will discuss in detail with you the expected recovery period.
Follow-Up and Surveillance
Since hyperparathyroidism can recur in a small proportion of people, all patients are enrolled in our post-operative active surveillance program. This will entail serial bloodwork that our staff will monitor. If a patient is noted to have an increasing PTH or calcium on routine bloodwork, we will investigate for recurrence with parathyroid imaging studies.
At the Weill Cornell Endocrine Oncology program, we are dedicated to a patient-centered multidisciplinary approach to provide you with the most up-to-date treatment options and access to clinical trials for parathyroid disease.