Nodular thyroid goiter in adults

A thyroid nodule is a lump in the organ. Most nodules are small, but they can vary in size. Some of them can be easily felt or even seen through the skin, while others are only detected with special imaging procedures such as a thyroid ultrasound. The nodes of this organ are very common. Most are not dangerous or benign, but if you have a thyroid nodule, your doctor may recommend a biopsy.

Thyroid nodules usually do not cause any symptoms and do not interfere with normal thyroid function. Most people don’t know they have nodules in this organ until a doctor discovers them during a routine physical exam or accidentally sees them during a computed tomography (CT) scan, ultrasound, or x-ray for other reasons.

A goiter is any enlargement of the thyroid gland. Sometimes the same person develops multiple thyroid nodules, a condition called multinodular goiter. When this happens, the thyroid gland usually enlarges and can cause discomfort in the neck.

What is nodular goiter

The thyroid gland is located in the lower part of the neck, below the vocal apparatus (larynx) and above the collarbones. A thyroid nodule is a lump in or on the thyroid gland. Thyroid nodules are found in about 6% of women and 1-2% of men, they occur 10 times more often in older people, but are usually not diagnosed.

Any time a lump is found in thyroid tissue, the possibility of malignancy (cancer) must be considered. Over 95% of thyroid nodules are benign (non-cancerous), but tests are needed to determine if a nodule is cancerous.

Benign nodules include:

Multinodular goiter. It is also called non-toxic goiter. The word “goiter” in this case means that the thyroid gland has become too large. This usually happens when the pituitary gland, the regulating gland in the brain, produces too much thyroid-stimulating hormone. If the goiter is small, the problem can be treated with pills (synthetic thyroid hormone). Surgery is necessary in cases where the goiter is large or does not stop growing after taking hormones. A large thyroid gland can put pressure on your windpipe (windpipe) or esophagus, make it hard to breathe, or interfere with eating.

Benign follicular adenomas. The word “follicular” means that the cells look like a group of small circles under a microscope. If follicular cells are contained within the nodule, the condition is called benign. If the cells have invaded the surrounding tissue, the diagnosis is cancer.

Thyroid cysts. These are nodules filled with fluid. If a knot has both liquid and solid parts, it is called a complex knot. They must be removed surgically if they cause neck pain or difficulty swallowing.

Causes of nodular thyroid goiter in adults

Nodules can be caused by a simple overgrowth of normal thyroid tissue, fluid-filled cysts, inflammation (thyroiditis), or a tumor (benign or malignant). Most nodules were removed surgically until the 1980s. In retrospect, this approach led to many unnecessary surgeries, as less than 10% of the removed nodules were found to be malignant. Most of the removed nodules could simply be observed or treated with medication.

The key cause of nodules is chronic thyroiditis (Hashimoto’s disease). This is a slowly developing inflammation of the thyroid gland. This often results in decreased thyroid function (hypothyroidism). Thyroiditis occurs when the body’s immune system destroys thyroid cells. Chronic thyroiditis is most common in women and people with a family history of thyroid disease.

Doctors don’t always understand why some people get nodules, but they are very common. Nodules are sometimes associated with other medical conditions, including:

• iodine deficiency in food and water;
• hyperthyroidism (overactive thyroid);
• cancer;
• autoimmune variants of thyroiditis with hypothyroidism.

Symptoms of nodular thyroid goiter in adults

Thyroid nodules are abnormal growths of cells in the organ and are very common in middle-aged people, especially women, although they can occur at any age. Thyroid nodules can be very small or very large, and are sometimes a mixture of fluid and solid thyroid tissue. Most nodules do not bother the person in any way, but if the nodule is large enough, it can cause local symptoms such as discomfort and trouble swallowing.

Types of thyroid nodules:

Thyroid cyst. It’s just a fluid-filled thyroid nodule. It is almost always benign and can fluctuate in size.

Goiter. This is an enlarged thyroid gland that protrudes from the neck. It can be caused by dietary iodine deficiency, but is most commonly caused by an immune defect that causes hormone fluctuations.

Substernal goiter. This is a condition where the thyroid gland becomes very large and extends below the sternum, where it can compress the windpipe in a hard to reach place.

Most thyroid nodules and cysts cause no symptoms and go unnoticed. However, if they are large enough (and this is a different amount of tissue for everyone), the most common symptoms are:

• pressure in front of the neck;
• difficulty or discomfort swallowing solid foods;
• breathing problems in a horizontal position;
• increased snoring due to growth under the sternum (substernal goiter);
• sudden persistent cough;
• visible protrusion on the neck.

A tumor in the neck should be reported to the doctor, even if there are no symptoms.

Treatment of nodular thyroid goiter in adults

Often, a doctor finds a lump during a routine examination or other tests. He can feel the knots under his arms. Then a more targeted diagnosis is needed.

Diagnostics

Thyroid nodules themselves, their possible causes and sizes, are diagnosed only after a series of tests.

Fine needle biopsy of the thyroid gland is a simple procedure that can be performed in a doctor’s office. Some doctors anesthetize the skin over the nodule before the biopsy, but anesthesia is not necessary and patients can usually return to work or home after the procedure without any side effects.

This test provides information that no other test can offer other than surgery. The use of fine needle biopsy has dramatically reduced the number of patients undergoing unnecessary surgery for benign nodules. However, about 10 to 20% of biopsy specimens are interpreted as inconclusive or inadequate, meaning the pathologist cannot be sure whether the nodule is malignant or benign. In such cases, a physician experienced in treating thyroid disorders may use other criteria to decide on surgery.

Thyroid Scan is an x-ray of the thyroid gland taken after an injection or ingestion of a small dose of a radioactive isotope, usually concentrated by the cells of the organ. The scan shows whether the nodule shows signs of hyperfunction (a “hot” nodule). Since cancer is rare in hot nodules, a scan showing a hot nodule eliminates the need for a fine needle biopsy. If a hot knot is causing hyperthyroidism, it can be treated with radioactive iodine or surgery.

Neither a thyroid scan nor radioactive iodine treatment should be given to a pregnant woman. A small amount of radioactive iodine is excreted in breast milk. Since radioiodine can cause irreparable harm to the infant’s thyroid gland, breastfeeding is not allowed for women who are undergoing radioiodine treatment.

US – In a thyroid ultrasound, high-frequency sound waves travel through the skin and are reflected back into the machine, producing detailed images. Ultrasound can visualize nodules up to 2–3 mm in size. Ultrasound can distinguish thyroid cysts (fluid-filled areas) from solid nodules. Recent advances in ultrasound are helping doctors identify nodules that are more likely to be cancerous.

Thyroid ultrasound is also used to guide a fine needle when aspirating thyroid nodules. Ultrasound guidance allows doctors to biopsy the nodule to obtain enough material to interpret the results. Even if the thyroid biopsy specimen is found to be benign, the size of the nodule should be monitored. Ultrasound examination of the thyroid gland is an objective and accurate method for determining changes in the size of the nodule. If it is a benign biopsy site that is stable or decreasing in size, it is unlikely to be malignant or require surgical treatment.

Modern treatments

Most patients who develop benign nodules do not require special treatment. Some doctors prescribe the hormone levothyroxine in the hope of preventing nodules from growing or reducing the size of cold nodules. Radioiodine can be used to treat hot nodules.

In a patient with a known thyroid nodule, the first step is to determine the risk of cancer. High risk factors include:

• a man under 40;
• a history of radiation therapy to the head or neck;
• large lymph nodes in the neck;
• problems with swallowing;
• problems with conversation;
• family history of thyroid cancer.

If the lesion is benign, the patient is monitored for nodule growth or development of new nodules. If there is growth, a second biopsy may be performed. If the lesion is malignant, the patient is referred to a surgeon for removal of the thyroid gland.

In about 10% of cases, a pathologist cannot make a diagnosis from a biopsy. This suggests an increased risk of malignancy, which may require surgery or observation. In most surgeries, the thyroid gland is completely removed (total thyroidectomy). Lymph nodes may also be removed to determine if the tumor has spread beyond the thyroid gland. Subsequent therapy depends on the results obtained during the operation.

Some patients may be given thyroid hormone followed by blood tests and ultrasounds, while others receive radioactive iodine to destroy residual thyroid tissue, followed by blood tests and ultrasounds.

For patients who do not require surgery (the majority of people), the best nodule monitoring schedule is developed. This will depend on whether the person had a biopsy, how long they had the nodules, and how they look on the ultrasound. Most people will not need a second biopsy once they have received a benign biopsy, and they do not need to have their thyroid nodules examined annually for the rest of their lives.

Prevention of nodular thyroid goiter in adults at home

Doctors aren’t sure what causes most thyroid nodules, so it’s likely that a person won’t be able to prevent them from developing. It’s worth making sure you’re eating enough foods that contain iodine (salt, dairy, seafood, meat, etc.) to prevent one of the causes of thyroid nodules.

Popular questions and answers

Questions regarding thyroid nodules, we discussed with general practitioner, endoscopist, head of the organizational and methodological office Lidia Golubenko.