Toxic Multinodular Goiter Treatment in Delhi, India

The thyroid gland produces hormones that regulate various functions in the body. When the diseased thyroid gland enlarges, it is called goiter.

A goiter with multiple nodules is termed multinodular goiter. The reasons for its development are not known. Multinodular goiter is most often asymptomatic. However, they are associated with a higher risk of cancer. Its treatment depends on:

• Whether the patient has a history of hyperthyroidism
• The size of the goiter
• Whether any of the nodules are malignant

Toxic multinodular goiter, or TMNG, contains at least two autonomously functioning nodules that produce excessive thyroid hormones. In the elderly, multinodular goiter is the most common cause of hyperthyroidism. This type of goiter develops slowly and is diagnosed only on routine blood tests. It may evolve to cause a critical condition, thyrotoxicosis. 

In Graves' disease, near-total thyroidectomy (NTT) is the treatment of choice, but the optimal therapy for TMNG is debatable. 

Typically, there are two treatment options for TMNG: 

1. Radioiodine therapy (RAI) 
2. Thyroidectomy

Anti-thyroid drugs are rarely successful in the long term. If surgery is not an option, percutaneous ultrasound-guided ethanol injection in the toxic nodules can be helpful. Thyroidectomy may be a beneficial choice of treatment for the disorder. However, patients will be subjected to the risk of surgery and the possible complications of recurrent nerve injury and hypocalcemia.

Symptoms of Toxic Multinodular Goiter

Most multinodular goiters are asymptomatic and are diagnosed during a regular physical examination. Some symptoms of multinodular goiter are:

• Sudden and unexplained weight loss
• Rapid heartbeat
• Increased appetite
• Tremors, usually in your hands
• Profuse sweating
• Increased sensitivity to heat
• Nervousness or anxiety

A large multinodular goiter can also present clinical symptoms, especially when it expands to the chest. Such a condition presents the following symptoms:

• Difficulty breathing or swallowing.
• The feeling of food being stuck in the throat.
• Experiencing a feeling of fullness in the neck.
• Large goiters are sometimes visible in the neck.

Causes of Toxic Multinodular Goiter

Multinodular goiter is a result of the following conditions:

• Iodine deficiency - Without adequate quantities of iodine, the thyroid hormones cannot produce enough hormones, leading to multinodular goiter.
• Genetically inherited
• A family history of multinodular goiter
• History of autoimmune diseases like Hashimoto's thyroiditis, Graves' disease
• A person may suffer from a multinodular goiter without a known cause.

Diagnosis of Toxic Multinodular Goiter

Doctors enquire about the patient's health conditions, ongoing medications, and personal or familial history of goiter or thyroid-related disorders. A physical examination may reveal one or many nodules in the thyroid. In addition, the thyroid appears enlarged, and there may be a rapid heart rate or a tremor.

Lab Tests

• Third-generation thyroid-stimulating hormone (TSH) assays: These tests provide the best screening for hyperthyroidism. Patients with TMNG show suppressed TSH levels.
• Nuclear Scanning: This scan is applicable to patients with biochemical hyperthyroidism. Patchy uptake is seen in patients with toxic multinodular goiter. 
• Ultrasonography: This is a highly sensitive procedure for delineating discrete nodules that are not palpable during thyroid examination.
• Blood tests: These help diagnose thyroid problems, especially thyroid-stimulating hormone (TSH) tests. If TSH levels are low, it indicates hyperthyroidism. If TSH levels are high, hypothyroidism may be indicated.
• Biopsy: A biopsy may be done to scan for cancer cells within the nodules. A standard biopsy method uses a small needle guided by an ultrasound, known as fine-needle aspiration (FNA). A biopsy can be done if the nodule is larger than 1 cm.

Other tests may include:

• Serum thyroid hormone levels (T3, T4) (elevated levels)
• Serum TSH (thyroid-stimulating hormone) (decreased levels)
• Thyroid uptake and scan or radioactive iodine uptake (this test may show increased uptake of radioactive iodine)
• Thyroid ultrasound

Treatment of Toxic Multinodular Goiter

The treatment of toxic multinodular goiter depends on its size, signs and symptoms, and underlying cause. If the goiter is small and thyroid function is healthy, the doctor would recommend a monitoring approach with timely check-ups.

Medicines

Medications for TMNG may include the following:

• To increase hormone production: Replacing the thyroid hormone can help treat an underactive thyroid. Some medications replace T-4, which results in lowered levels of TSH released by the pituitary gland. Some medications replace T-3 hormones and may decrease the size of the goiter.
• To reduce hormone production: An anti-thyroid drug disrupting hormone production is used to treat an overactive thyroid. It may additionally reduce the size of the goiter.
• For hormone-blocking activities: Beta-blocker drugs are prescribed to manage symptoms of hyperthyroidism, such as high blood pressure. They can disrupt the excess thyroid hormones and lower symptoms.
• For managing pain: If thyroid inflammation results in pain, it's usually treated with aspirin, naproxen sodium, ibuprofen, or related pain relievers. For severe pain, steroids can be given.

Surgery

The thyroid gland may need to be removed surgically. Sometimes, only a part of the thyroid is removed (partial thyroidectomy). Goiter presenting with the following complications requires surgical intervention:

• Difficulty breathing or swallowing
• Thyroid nodules that cause hyperthyroidism
• Thyroid cancer

Depending on the amount of thyroid removed, thyroid hormone replacement therapy may be needed to achieve better results.

Radioactive iodine therapy

iodine, taken orally, suppresses an overactive thyroid gland. The thyroid gland absorbs the radioactive iodine and destroys thyroid cells. The treatment eliminates or reduces hormone production. Additionally, it may decrease the size of the goiter.

Complications of Toxic Multinodular Goiter

Complications of multinodular goiter are associated with the organs their produced hormones affect. These include:

• Heart complications like heart failure, irregular heartbeat (atrial fibrillation), rapid heart rate
• Bone complications like bone loss leading to osteoporosis
• Hyperthyroidism
• Thyroid crisis: A thyroid crisis, also known as a thyroid storm, is an acute worsening of the symptoms of hyperthyroidism. It may occur simultaneously with infection or stress.
• Difficulty breathing or swallowing due to pressure on the airway passage (trachea) or esophagus behind the thyroid.

Risk Factors of Toxic Multinodular Goiter

Some factors that contribute to the development of multinodular goiter are:

• Women are at an increased risk
• Iodine deficiency
• Age over 40 
• History of radiation therapy performed in the head and neck area
• People with a family history of thyroid nodules

Prognosis of Toxic Multinodular Goiter

Most multinodular goiters are asymptomatic. However, if the symptoms of hyperthyroidism are evident, or there is difficulty in breathing or swallowing, contact the doctor or medical facility immediately.

Multinodular goiters increase the risk of developing thyroid cancer. However, they can be cured with medication, radioactive iodine therapy, or surgery. Multinodular goiters, in general, are not life-threatening.

Review

Reviewed by Dr. Jimmy Pathak, Consultant - Endocrinology & Diabetes, Diabesity Clinic.