Thyroid nodules are lumps that have formed in the thyroid, a small butterfly-shaped gland located at the base of the neck that plays a vital role in the body’s endocrine system. The nodules can be either solid or filled with fluid. While some thyroid nodules can be cancerous, the majority are benign; however, it is crucial to seek early treatment at the first sign of a thyroid nodule until the nature of the nodule can be determined.
Thyroid Nodule Symptoms
A large proportion of thyroid nodules do not have noticeable symptoms; however, in 4% to 7% of cases, the nodules are palpable, and 67% of nodules are found via ultrasound. On rare occasions, the nodule may make it difficult to breathe or swallow due to inflammation pressing on the windpipe or esophagus.
A potential complication that can arise with thyroid nodules is excess production of the hormone thyroxine. When this happens, patients may exhibit signs of hyperthyroidism, including:
- Unexplained weight loss
- Hyperhidrosis (excess sweating)
- Tremors
- Anxiety or nervousness
- Rapid, irregular heartbeat
While only a small number of thyroid nodules are cancerous, it is impossible to determine without evaluation by an endocrinologist. If you discover a nodule on your thyroid, you should visit an endocrine specialist as soon as possible. They can perform an ultrasound or fine-needle aspiration biopsy to determine whether the nodules are benign or malignant.
You should also visit an endocrinologist immediately if you have any of the following symptoms, which could indicate a more serious issue:
- Unintentional weight loss despite a regular (or increased) appetite
- Noticeable blood pressure increases, which can manifest itself as a pounding heartbeat
- Difficulty falling or staying asleep
- Noticeable muscle weakness or decrease in strength
- Unusual anxiety, nervousness, or irritability
- Constant cold feeling
- Unusually dry skin
- Issues with memory and information recall
- Loss of stamina
- Constipation
- Depression
Diagnosing Thyroid Nodules
There are several ways your doctor can diagnose thyroid nodules; your doctor’s main goal is to rule out thyroid cancer or thyroid dysfunction, like hyperthyroidism or hypothyroidism.
Some methods of diagnosis include:
A Physical Exam
The simplest and most common way to diagnose a thyroid nodule is through a physical exam performed by your doctor. This exam will involve your doctor asking you to swallow as they examine your thyroid.
Typically, the nodule will move vertically while swallowing. They will also palpate your neck to assess the location and size of the nodule. Your doctor will likely perform additional tests after examining your thyroid for nodules, primarily for hyperthyroidism and hypothyroidism.
Thyroid Function Tests
Thyroid function tests are another common way to identify thyroid nodules. Your doctor will prescribe blood tests to look at thyroid-stimulating hormone (TSH) and thyroxine (T4) levels in the blood. They will also look for elevated or suppressed levels of thyroid-related hormones like parathyroid hormone (PTH).
Ultrasound Tests
Thyroid ultrasound imaging tests may be used to evaluate your thyroid for possible nodules, cancer, or impaired function. Ultrasound imaging involves using high-frequency sound waves to produce an image of the thyroid. This imaging helps doctors identify the nature, volume, and number of thyroid nodules.
Fine-Needle Aspiration Biopsy
Fine-needle aspiration biopsies are commonly performed to distinguish benign nodules from cancerous tumors.
The biopsy involves the insertion of a small needle, which is guided into place with help from ultrasound imaging, into the nodule. The needle removes a small number of cells which will then be sent to a lab for analysis. Fine-needle aspiration biopsy procedures are performed in the doctor’s office and can take less than 30 minutes.
Thyroid Scan
A thyroid scan involves the injection of an isotope of radioactive iodine, typically into a vein in the arm. A camera system will then produce images of your thyroid. If the nodule absorbs more of the radioactive isotope than normal thyroid tissue would, it is considered a hot nodule and is most likely non-cancerous.
If the nodule absorbs less of the isotope than normal thyroid tissue, it is considered a cold nodule, which carries a higher risk of thyroid cancer. Although thyroid scans can help doctors gain more information on the nodule, it is not possible to diagnose a nodule as cancerous with 100% accuracy with this test.
Causes of Thyroid Nodules
There are several possible causes of thyroid nodules, including:
Thyroid Cyst
Cysts are fluid-filled cavities most commonly caused by the degeneration of thyroid adenomas, defined as overgrowths of normal thyroid tissue. Sometimes, these cysts contain solid components within the fluid; they are usually non-cancerous but can contain cancer on rare occasions.
Chronic Thyroid Inflammation
Chronic thyroid inflammation, also called Hashimoto’s disease, can lead to enlarged nodules. Chronic thyroid inflammation is often accompanied by hypothyroidism.
Normal Tissue Overgrowth
Sometimes, normal thyroid tissue can overgrow. This is referred to as thyroid adenoma. While the underlying mechanism behind thyroid adenoma is unknown, it is not cancerous. Usually, it does not require treatment unless the size of the growth is causing problems for the patient. Thyroid adenoma is sometimes accompanied by hyperthyroidism.
Multinodular Goiter
The term goiter is used to describe the enlargement of the thyroid gland. Goiters are commonly caused by a thyroid disorder or an iodine deficiency. Multinodular goiters contain multiple separate nodules within the goiter.
Iodine Deficiency
The thyroid can sometimes develop nodules if a patient has an iodine deficiency. Iodine is a necessary nutrient for proper thyroid function and the endocrine system.
Unfortunately, iodine deficiency (a major risk factor for thyroid issues and mental disabilities) affects approximately two billion people worldwide. Iodine deficiency is relatively rare in the United States since the vast majority of table salt is fortified by the nutrient.
Thyroid Cancer
While thyroid nodules are statistically unlikely to be cancerous, there are a small proportion of cases in which the nodule is cancerous. Cancer is more likely if your nodule is painful or very large.
Treating Thyroid Nodules
There are only a handful of treatment options for benign thyroid nodules. You may require surgery to remove the cancer cells if cancer is present. Surgical removal is only necessary for cancerous nodules. Benign thyroid nodule treatment options include:
Thyroid Radiofrequency Ablation
Thyroid radiofrequency ablation is a cutting-edge, minimally invasive thyroid treatment. The doctors at Associated Endocrinologists are proud to be one of the few endocrinologist practices in Michigan to offer the treatment.
Thyroid radiofrequency ablation is an FDA-approved, non-surgical treatment that shrinks thyroid nodules without impairing normal thyroid and endocrine function.
The procedure uses alternating currents transmitted to an electrode needle, creating heat. The heat is transferred from the electrode to the surrounding thyroid tissue, cauterizing the abnormal cells. The heat lesions cause the nodule’s cells to die, leading to a significant reduction in the size of the nodule. The treatment is a first choice where available as it can save patients from undergoing surgery.
Radioactive Iodine Therapy
Radioactive iodine therapy is primarily used for nodules that cause hyperthyroidism. The treatment is relatively common and has been in use for over 50 years. To undergo radioactive iodine therapy, patients will drink a small amount of water containing radioactive iodine through a straw. The treatment only needs to be performed once.
Associated Endocrinologists and Thyroid Nodules
At Associated Endocrinologists, we are proud to be one of the leading endocrinology practices in the United States and one of only a few practices in Michigan to offer thyroid radiofrequency ablation for treating thyroid nodules.
If you have symptoms of thyroid dysfunction or believe you have developed a thyroid nodule, call us at (248) 940-3785 and schedule a consultation today.