Thyroid Nodules: Causes, Symptoms and Treatment

A thyroid nodule is a fluid-filled or solid lump of cells that develop in the thyroid gland - a small, butterfly-shaped gland at the base of the neck, above the breastbone. They are relatively common and usually cause no symptoms. The doctor may discover a thyroid nodule during imaging tests such as a CT scan and MRI to diagnose another health condition. More than 90% of thyroid nodules are benign (noncancerous) and not serious. However, in rare cases, they can be cancerous.

Thyroid nodules can develop in both children and adults. However, they are around four times more common among females. Thyroid nodules can be classified as the following:

1. Solitary Nodule: When there is a single nodule in the thyroid gland
2. Multiple Nodule: When there is more than one nodule in the thyroid gland
3. Cystic Nodule: These are fluid-filled nodules in the thyroid gland
4. Solid Nodule: These are nodules with little fluid and too many cells

Further, thyroid nodules can be classified as cold, warm, or hot based on whether or not they produce thyroid hormones. 

1. Cold nodules: These nodules do not produce thyroid hormones (thyroxine). They may be benign or malignant. 
2. Warm nodules: These nodules act as normal thyroid cells. 
3. Hot nodules: Hot nodules produce excess thyroid hormone (thyroxine) and are almost always noncancerous

Usually, thyroid nodule does not cause any symptoms. But, if the nodule gets large enough, one may be able to see them and experience the following symptoms:

1. Goitre (an enlarged thyroid gland)
2. Pain at the base of the neck
3. Trouble with swallowing
4. Difficulty in breathing
5. Hoarseness in voice

Hyperfunctioning or hot thyroid nodules can cause excess production of thyroid hormones, leading to symptoms of hyperthyroidism, including:

1. Palpitations (rapid and irregular heartbeat)
2. Unexplained weight loss
3. Increased appetite
4. Feeling nervous or shaky
5. Frequent bowel movements
6. Difficulty sleeping
7. Muscle weakness around the shoulders, hips, and sometimes face and throat
8. Light or missed menstrual cycle

Thyroid nodules may also cause low thyroid hormone levels, leading to symptoms of hypothyroidism, including:

1. Persistent fatigue
2. Tingling or numbness in hands
3. Unexplained weight gain
4. Dry skin and hair
5. Constipation
6. Sensitivity to cold
7. Brittle nails
8. Puffy face
9. High cholesterol
10. Joint pain or swelling
11. Depression
12. Memory loss
13. Heavy and frequent menstrual cycle

When the thyroid nodules become large, they may press on the airway or oesophagus, causing the following symptoms:

1. Difficulty swallowing and breathing
2. Discomfort while lying down in certain positions
3. Food getting stuck in the throat
4. Noisy breathing at night

The cause of a thyroid nodule is not always clear. Several medical conditions can cause nodule development in the thyroid gland. These conditions include:

1. Overgrowth of the thyroid tissue: Also known as thyroid adenoma, it is unclear why overgrowth of the thyroid tissue occurs. The growth is not cancerous and isn’t severe unless its size causes some troublesome symptoms. Thyroid adenoma can sometimes lead to hyperthyroidism. Thyroid adenoma usually develops due to heredity. 
2. Thyroiditis: It is chronic inflammation (swelling) of the thyroid gland caused by conditions such as Hashmito’s disease (an autoimmune disorder damaging the thyroid gland). Inflammation of the thyroid is often associated with hypothyroidism. 
3. Thyroid cysts: These are cysts or growths filled with fluid. Often this fluid is mixed with solid components. Usually, thyroid cysts are noncancerous, but sometimes they may contain solid cancerous elements. 
4. Multinodular goitre: A goitre is a thyroid gland enlargement caused by thyroid disease or iodine deficiency. Multinodular goitre contains multiple benign nodules. 
5. Thyroid cancer: The chances of a nodule being cancerous are very small - less than 5% of all thyroid nodules. However, there may be chances of cancer when a large and complex nodule causes pain and discomfort. 
6. Grave’s disease: An autoimmune disease where the immune system mistakes healthy cells for foreign bodies and thus attacks them. It causes an overactive thyroid, i.e., excess thyroid hormone production. 
7. Iodine Deficiency: A diet that lacks iodine can also sometimes cause the thyroid glands to develop thyroid nodules.

Thyroid nodules are more common in people who live in countries with iodine-deficient diets. Iodine is necessary for the thyroid gland to produce thyroid hormones essential for a body to function correctly. Several factors increase the risk of developing thyroid nodules, including:

Uncontrollable factors that can lead to a thyroid nodule

1. Exposure to thyroid X-rays during infancy or childhood
2. Family history of thyroid nodules
3. 60 years or older
4. Gender (more common in women; however, when they develop in men, they are more likely cancerous)
5. Pre-existing thyroid conditions, such as Hashimoto’s disease

Controllable factors that can contribute to the growth of a thyroid nodule

1. Smoking
2. Alcohol consumption
3. Obesity 

Since the cause of thyroid nodule is not always known, it is difficult to prevent it in most cases. However, one can decrease the risk by managing certain modifications in the lifestyle. 

1. Try to quit smoking.
2. Exercise regularly and eat a healthy diet to manage weight.
3. Make sure to eat a diet with enough iodine.

When to See a Doctor?

Although most thyroid nodules are noncancerous and do not cause serious problems, the advice of a doctor if there is any unusual swelling in the neck. Consult a healthcare professional if experiencing signs of hyperthyroidism (sudden weight loss, trouble sleeping, pounding heart, nervousness) or hypothyroidism (fatigue, dry skin, coldness, depression, constipation, memory problems). The healthcare professional will refer to an endocrinologist for thyroid-specific issues. 

Sometimes, it's possible to see or feel a thyroid nodule. The doctor may detect a nodule during imaging tests for another condition. If they suspect a thyroid nodule, they will refer to an endocrinologist. During diagnosis, the endocrinologist will ask about the medical and family history. Furthermore, they will ask if any radiation treatment was done on the neck or head during infancy or childhood. Next, they will order the following tests to diagnose a thyroid nodule:

1. Physical exam: During a physical exam, the healthcare provider will likely ask the person to swallow as a thyroid nodule will move up and down in the throat while swallowing. They will also look for signs of hyperthyroidism and hypothyroidism. 
2. Thyroid blood test: These tests measure the level of Thyroid-Stimulating Hormone (TSH) and thyroid hormones (T3, T4, and Thyroid Antibodies) in the blood. It helps check whether someone is suffering from hyperthyroidism or hypothyroidism. 
3. Ultrasound: The imaging test produces images of the thyroid gland. A thyroid ultrasound helps determine the shape and structure of the nodules. Moreover, it helps the doctor distinguish between fluid-filled and solid nodules. Doctors also use ultrasound to guide the needle placement in fine-needle aspiration biopsy. The ultrasound forms images to locate the right area for fine-needle aspiration. Using these images, the doctor inserts a thin needle attached to a syringe through the skin into the abnormality within the thyroid. 
4. Fine-needle aspiration biopsy: The test is performed to ensure that the nodules are noncancerous. During the test, the doctor inserts a very thin needle in one or more nodules to take a sample of cells. These samples are then analysed under a microscope in the laboratory. 
5. Thyroid scan: It is performed to check whether the nodule is cold, warm, or hot. The doctor injects a small amount of radioactive iodine (a treatment for overactive thyroid and thyroid cancer) into a vein in the arm. A special camera then produces images of the thyroid gland on a computer screen. The doctor will evaluate how much radioactive iodine is absorbed by thyroid nodules and the normal thyroid tissue.

How to Prepare for Doctor Consultation?

1. While preparing for a doctor consultation, make sure to:-
2. Take a prior appointment
3. Note down the symptoms
4. Make a list of personal and family medical history
5. Make a note of all the medications, herbs, and supplements
6. Write down any further questions for the doctor

One must expect the following questions from the doctor during the visit:

1. When were the symptoms experienced at first?
2. Any family history of nodules?
3. Any thyroid radiations were experienced as an infant or child?
4. Do they have other pre-existing thyroid conditions?
5. Does anything improve or worsen the symptoms?

Here’s what could be asked to the doctor about the condition:

1. What is the cause of the symptoms?
2. Are these nodules cancerous or noncancerous?
3. What diagnostic tests are needed?
4. How to prepare for the diagnostic tests?
5. Are any changes required in the diet?
6. What should be included in a healthy diet?
7. How to prevent progression?
8. What are the treatments for the nodules that don’t cause any problems?
9. What are the available treatment options, and which one is most recommended?
10. Is surgery needed?
11. Can it be managed without surgery?

Problems might arise when a nodule or goitre produces excessive amounts of thyroid hormone, which causes the hormone to build up in the body. Complications of having a thyroids nodule:

1. Problems with thyroid nodule surgery: If one already had surgery to remove nodules, they will need thyroid hormone replacement therapy for the rest of the life. 
2. Difficulty swallowing or breathing: Large thyroid nodules can interfere with breathing and swallowing. 
3. Hyperthyroidism: When a nodule produces thyroid hormone, it can lead to an excess hormone level in the body, causing hyperthyroidism. The potential complications of hyperthyroidism include weak bones, irregular heartbeat, and thyroid storm (a rare but life-threatening condition when the thyroid suddenly releases large amounts of thyroid hormone). 

The treatment depends on the type of thyroid nodule. For example, if a thyroid nodule increases in size and number, the doctor may suggest the following treatment methods.

Thyroid Nodule treatment without surgery

1. Benign Nodules
   The treatment options for benign (noncancerous) thyroid nodules include:
   1. Watchful waiting: If the thyroid nodules are not cancerous, the doctor may suggest watching the condition. The doctor will regularly evaluate changes in the nodules. If the benign nodule remains unchanged,  one may never need treatment. 
   2. Thyroid hormone therapy: When the thyroid gland is not producing enough thyroid hormones, the doctor may recommend thyroid hormone therapy. The treatment uses artificial thyroid hormones to raise the body’s low levels of natural hormones. 
2. Nodules that Lead to Hyperthyroidism
   If a thyroid nodule is producing excess thyroid hormones, the doctor may recommend the following treatment options:
   1. Anti-thyroid medications: Anti-thyroid medications such as methimazole can help reduce hyperthyroidism symptoms in some cases. It is a long-term treatment that can have serious side effects on the liver. Therefore, it is important to discuss risks and benefits with the doctor. 
   2. Radioactive iodine: Radioactive iodine taken as a capsule o the liquid form gets absorbed by the thyroid gland. The iodine causes nodules to shrink and reduce hyperthyroidism symptoms within two to three months. 
3. Cancerous Nodules
   ​​​​​​​Treatment for cancerous nodules includes:
   1. Observation: Tiny cancerous nodules have low chances of growing. Therefore, the doctor may prefer closely observe them before treatment. Observation includes tests such as ultrasound and blood tests. 
   2. Alcohol ablation: Certain small cancerous nodules can also be treated with alcohol ablation. In this method, the doctor injects a small amount of alcohol into a cancerous nodule to shrink it. One may need multiple sessions for effective treatment. 

Thyroid Nodule treatment with surgery

1. Benign Nodules
   The doctor may recommend surgery if a large noncancerous nodule or multinodular goitre constricts the oesophagus or airway, making it hard to swallow or breathe. Suspicious nodules may also require surgical removal to be examined for cancer. 
2. Nodules that Lead to Hyperthyroidism
   If the other two treatment options are unsuitable, the doctor may recommend surgery to remove the overproductive thyroid nodule. 
3. Cancerous Nodules
   It is the most common treatment option for cancerous nodules. Traditionally, a significant part of the thyroid tissue was removed by a total thyroidectomy procedure. Today, however, only half of the thyroid is released in a limited surgery. After the surgery, there is a need for lifetime treatment with levothyroxine (a medicine used to treat hypothyroidism) to supply thyroid hormone to the body. 

The type of thyroid nodule determines the best course of medical treatment. There are numerous ways to reduce thyroid nodules through dietary changes.

1. Foods rich in B vitamins and zinc, such as spinach, cashews, grass-fed beef, chicken, eggs, mushrooms, and asparagus
2. Consume adequate iodine-rich foods to avoid one of the causes of thyroid nodules, such as table salt and dairy products.
3. Spinach, halibut, salmon, cashews, sunflower seeds, brazil nuts, and oats high in selenium.
4. Food with high Vitamin D content like Egg yolks, mushrooms, and some fish, such as mackerel, salmon, and tuna.