What are thyroid nodules?

Thyroid nodules are growths or lumps that form on the thyroid gland—a butterfly-shaped gland located at the base of the neck, in front of the trachea (breathing pipe). This gland produces hormones that can affect body metabolism. Thyroid nodules can be solid or fluid-filled, and will usually only be detected during a routine physical examination or imaging study such as an ultrasound, CT scan, or MRI. Most thyroid nodules are benign but some can be malignant and require further evaluation and treatment.

What causes thyroid nodules?

Thyroid nodules can form due to several reasons.

• Colloid nodules: Overgrowths of normal thyroid tissue. These are non-cancerous, and are the most common type.
• Thyroid cysts: Fluid-filled cysts. These are usually non-cancerous.
• Chronic inflammation of the thyroid: A thyroid disorder can cause enlarged nodules.
• Multinodular goitre: This can occur when there are multiple nodules in the thyroid gland. 
• Hyperfunctioning thyroid nodules: These nodules produce extra thyroid hormones, which may lead to hyperthyroidism.
• Thyroid cancer: This may be associated with a family history of thyroid cancer or childhood exposure to radiation.

Symptoms of thyroid nodules

Thyroid nodules don’t usually present with symptoms, but if they are numerous or large enough, they may be visible in the neck. Occasionally, thyroid nodules can reach a size that causes difficulty with swallowing, or breathing, hoarseness, pain in the front of the front of the neck, or an enlargement of the thyroid gland. 

These nodules can also produce excessive amounts of thyroid hormones. This can cause:

• Irregular or rapid heart palpitations
• Tremors
• Anxiety
• Difficulty sleeping
• Increased sweating
• Weight loss

Prevention and treatment

As the exact cause of the majority of thyroid nodules is not fully understood, it is difficult to determine what will help prevent them. However, you can decrease your risk of developing thyroid nodules by maintaining a healthier lifestyle. For example, quitting smoking, attaining a healthy weight, and getting enough iodine in your diet. 

If you have been diagnosed with thyroid nodules, the treatment options you have include:

• Regular checks: If the nodules are non-cancerous, the doctor may schedule you for regular follow-ups to check for any changes in the nodules instead.
• Radioactive iodine: This treats hyperfunctioning thyroid nodules and goitres by causing them to shrink.
• Surgery: This removes nodules that are suspected to be cancerous or causing obstruction to breathing or swallowing.