Thyroid Nodules: Diagnosis and Treatment
What are thyroid nodules?
Thyroid nodules are lumps or tumors in your thyroid gland. In general, thyroid nodules are very common, and the likelihood of having a thyroid nodule increases with age. Gender is also a factor, as nodules are three times more common overall in women compared to men.
Most thyroid nodules are benign and never become symptomatic or cancerous. In fact, the vast majority — as many as 95 percent — of thyroid nodules are not cancerous. These benign nodules can, however, be a sign of other thyroid conditions, including Hashimoto’s thyroiditis and toxic multinodular goiter.
Why do thyroid nodules develop?
Thyroid nodules can be solid, partially solid and partially fluid-filled (cysts), or pure fluid-filled cysts. They can also be solitary, or you may have several nodules.
Thyroid nodules can develop for a number of reasons:
- As a result of normal overgrowth of thyroid tissue, more common with age
- As a result of autoimmune Hashimoto’s thyroiditis
- As a result of autoimmune Graves’ disease
- As a result of infection
- As a result of cancer in the thyroid gland
How thyroid nodules are found
Thyroid nodules are typically found in a number of ways:
- By self-examination or a “neck check” you perform yourself
- By manual examination from your healthcare practitioner
- A partner or family member feels or sees a lump or enlargement in your neck
- By hairdressers, massage therapists, and others who handle your neck area
- On routine X-rays not related to your thyroid, such as dental X-rays, or X-rays to evaluate neck pain
- On ultrasound tests of the head, neck, and shoulders
What are the symptoms of thyroid nodules?
Thyroid nodules often don’t produce any symptoms, but when they do, it is often due to their size, their location, or their ability to produce thyroid hormone.
Some of the more common symptoms include:
- Feeling a lump in the neck
- Discomfort or difficulty swallowing
- A feeling of a tickle in the throat
- Some pain or sensitivity in the neck, jaw, or ear
- Enlargement of the neck
- A hoarse voice
- Discomfort with scarves, ties, and necklaces
- Feeling a lump in the throat when swallowing
If you have a hormone-producing nodule or nodules, you may experience some of the common signs and symptoms of hyperthyroidism, including anxiety, high heart rate, elevated blood pressure, insomnia, feeling hot, excessive sweating, thirst, diarrhea, and weight loss, among other signs and symptoms.
Seeing an expert
If you have a thyroid nodule, you should consider seeing an endocrinologist, experienced thyroid surgeon, otolaryngologist, ear/nose/throat surgeon, or another specialist with expertise in diagnosing and managing thyroid nodules. The process of diagnosing and treating thyroid nodules is better left in the hands of an expert rather than a general practitioner.
How are thyroid nodules evaluated?
Typically, evaluating a nodule or nodules involves a number of key steps:
Thyroid blood tests, including the thyroid stimulating hormone (TSH) test, are run to determine if the nodules are producing excessive amounts of thyroid hormone.
A thyroid ultrasound is performed, to evaluate the size, shape, location, and characteristics of the nodules, and to evaluate the nearby lymph nodes in the neck.
If a nodule has any suspicious characteristics — for example, it is growing quickly, or is larger than a half-inch in size — a fine needle aspiration (FNA) biopsy is typically performed.
The sample taken from the FNA is analyzed by a pathologist to determine if there is evidence of cancer. (Note: If the result is inconclusive, a variety of additional genetic tests — such as the Veracyte Afirma Thyroid Analysis, for example — may be performed to make a more definitive diagnosis.)
Ultimately, nodules are designated as benign or malignant (cancerous). Purely cystic thyroid nodules are usually benign. And when you have multiple nodules that produce thyroid hormone, they are almost always benign and are considered evidence of a condition known as toxic multinodular goiter.
Treatment for thyroid nodules: monitoring
If a nodule is benign, is not impairing your breathing or swallowing, and isn’t cosmetically unsightly, no further treatment may be needed. You doctor may recommend observation — also known as “watchful waiting” — and repeat blood tests and ultrasound every year, to see if your nodules are growing or changing.
Treatment for thyroid nodules: thyroid medication
There is very little evidence to support the effectiveness of thyroid hormone replacement medication to treat benign thyroid nodules. But in some cases, physicians prescribe a dose of medication, with the hope that it may slow or stall nodule growth by reducing the stimulation of thyroid tissue.
Treatment for thyroid nodules: surgery
With benign nodules, if they are cosmetically unsightly, affecting breathing or swallowing, or are producing thyroid hormone and symptoms can’t be controlled, surgery is typically recommended.
Treatment for thyroid nodules: radioactive iodine (RAI)
If you have toxic multinodular goiter — an enlarged thyroid, with multiple nodules that produce thyroid hormone — the treatment of choice is radioactive iodine (RAI) ablation. Research shows that a single dose of RAI has a success rate of 85 to 100 percent in patients with toxic multinodular goiter, in terms of reversing the overproduction of thyroid hormone, and typically reduces the size of the goiter by up to 40 percent.
Treatment for thyroid nodules: percutaneous ethanol injections (PEI)
Some thyroid cysts can be shrunk with a treatment known as ultrasound-guided percutaneous ethanol injections or PEI. Ethanol is injected directly into the thyroid cyst, and the precise administration is guided by ultrasound. PEI treatment is considered a safe and effective way to resolve cystic nodules of the thyroid gland.
High-intensity focused ultrasound ablation, radiofrequency ablation, laser ablation
If you have benign solid thyroid nodules, but you aren't a good candidate for surgery or are reluctant to have thyroid surgery, these techniques may be better treatment options to help shrink your nodule and reduce pressure in the area. They also allow you to avoid a visible scar and are far less likely to result in hypothyroidism when compared to surgery.
HIFU, high-intensity focused ultrasound ablation, focuses ultrasound waves at a nodule, causing the destruction of the nodule. HIFU ablation does not require a skin incision.
In laser or radiofrequency ablation, a laser is trained on the nodule to create heat that helps to destroy the nodule’s tissue. Laser and radiofrequency require a small incision for insertion of a needle.
Thyroid nodules in pregnancy
In some cases, thyroid nodules may be diagnosed during pregnancy. Nodules are more likely to grow in size while you are pregnant, and are more common after multiple pregnancies. According to the American Thyroid Association guidelines for management of thyroid disease during pregnancy, if nodules are detected during pregnancy, your practitioner should:
- Review your family or personal history of thyroid cancer, and thyroid or endocrine disorders
- Run thyroid blood tests, including a TSH and free T4 test
- Perform an ultrasound to determine the size and characteristics of your nodule
If the nodule does not appear suspicious and is less than 10 mm in size, your doctor may choose to monitor it.
If your nodule is larger than 10 mm, growing, has suspicious characteristics, or if the nodule is affecting your swallowing or breathing, a fine needle aspiration biopsy is recommended
Benign nodules during pregnancy are monitored but not typically treated unless they affect your swallowing or breathing. In that case, PEI, HIFU, laser or radiofrequency ablation may be used as a treatment, or surgery may be performed, typically during the second trimester.
If the nodules are cancerous, your doctor will make a recommendation depending on the type of thyroid cancer you have. For slower-moving, well-differentiated thyroid cancer, your doctor may monitor you with frequent thyroid ultrasounds, give you levothyroxine treatment, and start thyroid cancer treatment after childbirth. More aggressive cancer may be treated with surgery during the pregnancy.