آدنوم پاراتیروئید به چه معناست؟

غدد پاراتیروئید معمولاً شامل ۴ غده به اندازه نخود یا دانه برنج هستند که در ناحیه‌ گردن و اطراف غده‌ تیروئید قرار دارند. Their main function is to secrete parathyroid hormone (PTH), which by taking calcium from the bones and increasing its absorption from the kidney and intestine, helps to regulate the level of calcium needed for the proper functioning of the brain, heart, nerves and bones. A parathyroid adenoma is a benign mass (non-cancerous) that develops on one or more of the parathyroid glands. Parathyroid surgery is one of the main treatment methods for parathyroid tumor.

This abnormal growth causes the parathyroid gland to produce parathyroid hormone (PTH) in excess of the body's needs; This condition is called primary hyperparathyroidism. Too much parathyroid hormone disrupts the body's normal calcium balance and increases the amount of calcium in the bloodstream. An increase in the level of calcium in the blood leads to health problems such as kidney stones and osteoporosis.

Parathyroid adenoma

Parathyroid tumors are divided into two general categories based on the number of benign masses created in the parathyroid glands:

Single adenoma:

This case is the most common type of parathyroid adenoma, which accounts for about 85% of all hyperparathyroidism cases. In this case, only one parathyroid gland develops abnormally and turns into a benign mass (adenoma).

Multiple parathyroid adenomas:

This type is much less common (about 4-5% of all cases of hyperparathyroidism). Here, two or more parathyroid glands grow abnormally at the same time or at different times and become adenomas.

Symptoms caused by parathyroid adenoma, which leads to increased blood calcium levels (hypercalcemia), can be very diverse. However, many people do not have any noticeable symptoms and their disease is often diagnosed during routine blood tests for other reasons. Symptoms caused by parathyroid tumor include the following:

1. General symptoms and nervous system:

These symptoms occur due to the effect of excess calcium on the brain and body and include:

• Fatigue and weakness: feeling very tired, lethargy and muscle weakness
• Cognitive and mood disorders: confusion, memory loss, depression, irritability and intellectual problems such as confusion and brain fog (decreased concentration and memory)
• General pains: bone and joint pain and general pains without specific cause

2. Renal and skeletal symptoms:

Increasing blood calcium directly affects bones and kidneys and may lead to the following symptoms:

• Bone complications: osteoporosis, weak bones and increased risk of fracture
• Kidney complications: formation of kidney stones and frequent urination (especially at night)

3. Gastrointestinal and miscellaneous symptoms:

These symptoms occur due to the effect of high calcium on the digestive system and the cardiovascular system:

• Digestive complaints: constipation, abdominal pain, heartburn, nausea/vomiting and loss of appetite
• Blood pressure: suffering from high blood pressure

In most cases, there is no specific cause for the formation of these benign masses. However, several factors are known as risk factors or underlying causes that can directly or indirectly play a role in stimulating the parathyroid glands and causing adenoma.

1. Hereditary and genetic factors

About 10% of cases of parathyroid adenoma are hereditary and are often diagnosed at a younger age:

• Multiple endocrine neoplasia syndromes :(MEN) including MEN I and MEN IIA in which a changed gene is inherited from the parents and can involve other glands in addition to the parathyroid.
• Isolated familial hyperparathyroidism: This condition is an inherited genetic defect that predisposes a person to primary hyperparathyroidism (in fact, hyperparathyroidism runs in families). In these people, the defective gene causes the parathyroid gland or glands to grow abnormally and eventually appear as an adenoma (benign mass) and become overactive.

2. Environmental factors and lifestyle

Factors that can stimulate the parathyroid glands and increase the risk of adenoma formation:

• Gender and age: Parathyroid tumor is almost three times more common in women than in men, and the highest prevalence is seen in people aged 50 to 70.
• Radiation therapy: Exposure to radiation (such as a history of radiation therapy) in the head and neck area increases the risk of infection.
• Nutritional deficiencies: Chronic and long-term lack of calcium or vitamin D in the diet can stimulate the parathyroid glands and cause tumors.
• Drugs: Long-term use of certain drugs such as lithium may increase the risk of developing parathyroid adenoma.

Diagnosis of parathyroid adenoma

Diagnosis of parathyroid adenoma is a multi-step process that includes clinical, laboratory and imaging evaluation. The purpose of this process is to confirm primary hyperparathyroidism, determine the underlying cause of the adenoma, and determine the exact location of the tumor for better treatment planning.

1. Clinical evaluation and history taking from the patient

First, the doctor performs a complete clinical evaluation, which includes the following:

• Symptom Check: Ask questions about possible symptoms of high calcium, such as bone pain, muscle weakness, fatigue, kidney stones, and digestive problems.
• Medical history: Investigate family history of endocrine tumors and history of exposure to radiation therapy in the neck and head area, as well as the use of drugs such as lithium.

2. Definitive diagnosis of the disease (blood and urine test)

Diagnosis of primary hyperparathyroidism is determined only by measuring the level of calcium and parathyroid hormone (PTH) in the blood. The presence or absence of clinical symptoms in the patient has no effect on this diagnosis:

• Serum calcium: Initial diagnosis usually begins with the observation of an above-normal calcium level in a routine blood test.
• Parathyroid hormone :(PTH) The final diagnosis is confirmed by observing a higher than normal level of PTH in the blood along with high calcium.
• Serum phosphorus: measuring phosphorus is important; Because serum phosphorus levels are usually low in primary hyperparathyroidism. (hypophosphatemia)
• Kidney function: Tests such as creatinine and BUN are done to check the health of the kidneys.
• Urine test24hour: It is prescribed to measure the amount of calcium that the body excretes through urine.
Vitamin D deficiency has a negative effect on parathyroid function; Therefore, the level of vitamin D is also checked accurately.

3. Determining the location of the adenoma (imaging)

After confirming the definitive diagnosis, the specialist uses imaging tests to find the exact location of the adenoma so that the treatment process can be carried out with greater precision.

• Sestamibi scan: (Sestamibi Neck Scan) This specialized imaging method is used to identify the exact location of adenoma or hyperactive adenomas and has high sensitivity.
• Sonography of the neck: is done to observe the parathyroid and thyroid glands and confirm the presence of possible masses.
• CT scan (CT Scan) or MRI :(MRI) In more complicated cases where the results of ultrasound and sestamibi are not certain, CT scan or MRI may be used for more accurate imaging and determining the position of the adenoma.
• Fine needle sampling :(FNA) In rare cases, a small sample of the tumor is removed to confirm the histological diagnosis of adenoma.

Untreated parathyroid adenoma keeps blood calcium levels chronically high by continuously secreting parathyroid hormone (PTH). This hypercalcemia causes serious damage to the organs in the short and long term:

Chronic and long-term effects of not treating parathyroid tumor

The following are the most common complications caused by not treating this problem, which gradually weakens the body:

• Severe osteoporosis
• Chronic bone and joint pain
• Kidney stones
Kidney failure Chronic fatigue
• Brain fog (impairment of concentration and memory)
• Depression
• High blood pressure
• Digestive problems such as chronic constipation, nausea and increased risk of stomach ulcers

Acute and threatening side effects

The following symptoms occur due to a very strong and sudden increase in blood calcium and require immediate medical intervention:

• Parathyroid Crisis is a rare emergency condition characterized by a sudden and severe increase in calcium and leads to severe mental changes, kidney failure and, if untreated, coma and death.
• Cardiac arrhythmias (irregular heartbeats): Too much calcium disrupts the heart's electrical activity and sometimes causes severe heart irregularities.
• Death: A very strong increase in calcium without treatment may even lead to death.

Parathyroid adenoma treatment methods generally fall into two main categories: surgical treatment and non-surgical methods. The appropriate method for treating parathyroid tumor varies from person to person and is determined according to factors such as age, severity of symptoms, presence of serious complications (such as osteoporosis or kidney stones) and individual preferences of the patient.

Surgical treatment (parathyroidectomy)

Parathyroidectomy is known as the main and definitive treatment for parathyroid adenoma. Parathyroid adenoma surgery involves removing the parathyroid gland with adenoma and in more than 95% of cases, it leads to complete recovery of the disease. This surgery can be performed open or using minimally invasive techniques. The success of the operation depends on the experience and expertise of the surgeon in diagnosing and locating overactive parathyroid glands in the sensitive area of ​​the neck. It is very important to use tools such as a neurometer during surgery; These tools help the surgeon to identify the laryngeal nerve and prevent damage to it and increase the safety of the patient during the operation. Choosing the right surgical method and precision in the operation is the key to ensuring a high rate of treatment and preventing the recurrence of the disease.

Non-surgical treatments (management and monitoring)

These approaches are used for patients who are not candidates for surgery or who have mild symptoms:

• Active surveillance (observation): For small, asymptomatic or mild adenomas, the patient is regularly monitored for calcium levels and kidney function.
• Drug management: The goal of drug treatment for parathyroid adenoma is to manage complications caused by increased blood calcium and is not considered a definitive treatment (substitute for surgery). This management focuses on controlling calcium levels and protecting bones. The main drugs used include calcimimetics (such as cinacalcet) to reduce PTH and calcium, bisphosphonates (such as alendronate and zoledronic acid) to protect bones from osteoporosis, and in some cases calcitonin or estrogen replacement hormones for postmenopausal women.
• Destructive minimally invasive techniques: For some patients, minimally invasive methods such as radiofrequency ablation (RFA) or intraglandular ethanol injection (PEI) are used to destroy the parathyroid tumor.

• First, a small incision (usually about 1 to 2 cm) is made in the front of the neck.
• The surgeon examines all of the parathyroid glands to determine the abnormal gland or glands.
• If one or two glands have adenomas, they will be removed and the remaining healthy glands will be responsible for maintaining calcium levels.
• In cases of hyperplasia, i.e. if all four parathyroid glands are abnormal, 3 complete glands and part or half of the fourth gland are removed and some tissue remains.
• During the surgery, the level of parathyroid hormone (PTH) is measured quickly. If the adenoma has been removed, the PTH level should decrease by at least 50%.
• Using tools such as a neurometer to help the surgeon identify and protect the laryngeal nerve is very important to prevent voice changes.
• The removed gland is immediately sent to the laboratory so that the pathologist can confirm that the removed gland was indeed the fertile gland.

Note: The surgeon's ability to find and examine all four glands during the operation ensures the highest rate of successful and long-term treatment.

Complications Possible parathyroid tumor surgery

Parathyroid tumor surgery is associated with risks like any other operation; But choosing an experienced and skilled surgeon in the field of endocrinology minimizes the risk of complications. The following are the most common possible complications of parathyroid adenoma surgery:

Short-term or permanent decrease in blood calcium level (hypocalcemia): This is the most common risk of parathyroid surgery. Symptoms of hypocalcemia include numbness or tingling in the fingers and around the mouth, as well as muscle cramps.

Calcium loss after extensive surgery: In surgeries where 3 or more parathyroid glands are removed, you will definitely experience calcium loss symptoms in the first week after surgery.

To reduce these risks, take the following steps:

• Consumption of calcium and vitamin D supplements for two weeks after surgery, exactly according to the prescription and dosage prescribed by the doctor
• If more than 3 parathyroid glands are removed, you may need to take a higher dose of calcium.

Dr. Seyed Ahmad Fanai is a thyroid and parathyroid surgeon and a member of the American Thyroid Association. He, who is known as the Golden Paw thyroid surgeon, performs thyroid and parathyroid surgeries with the most up-to-date medical equipment such as neurometer, Harmony, etc. Preservation of the vocal nerve is very important in parathyroid tumor surgery.

The surgeon may face various challenges during surgery. For example, Dr. Fenai has performed rare and simultaneous surgery for parathyroid adenoma and thyroid cancer several times. Simultaneously performing this surgery should only be done by an expert and experienced surgeon. Dr. Fanai specializes in thyroid and parathyroid surgery. To schedule an appointment, call the numbers listed on the site or fill out the online reservation form.

End

Parathyroid adenoma is a benign mass and the main cause of hyperparathyroidism, which threatens the health of kidneys and bones. Parathyroid surgery (parathyroidectomy) is known as the definitive treatment of parathyroid tumor with a success rate of more than 95%. Performing this operation by an up-to-date and experienced surgeon minimizes the risk of possible complications.