Thyroid nodules are abnormal cell growths that form a lump in the thyroid gland. Most thyroid nodules are benign, but a small percentage are related to thyroid cancer.

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Thyroid nodules are often overlooked because they frequently have no symptoms and don’t affect hormone levels.

Although thyroid nodules are fairly common and usually benign, they can be cancerous. It’s important to monitor known thyroid nodules for any suspicious changes or rapid growth.

Read on to learn more about thyroid nodules and cancer risk.

Thyroid nodules are lumps in the thyroid gland caused by abnormal cell growth. You might have one or a cluster, and they can either be solid or filled with fluid.

Thyroid nodules are considered fairly common. Up to 50% of people in the United States have a thyroid nodule, and approximately 5% to 7% of adults have a thyroid nodule large enough to be detected by a physical examination alone.

Thyroid nodules are more common in females and older individuals. Other risk factors for thyroid nodules include:

Thyroid nodules often have no symptoms.

In some cases, you may notice a lump on your neck. In rare cases, you might experience pain in the neck, jaw, or ear. If a nodule is big enough, it may cause trouble breathing and swallowing, or you may feel a tickle in your throat.

More than 90% of identified thyroid nodules are benign. However, just 4% to 6.5% of nodules are caused by thyroid cancer.

Thyroid nodules are more likely to be cancerous when they develop in males or when an individual’s TSH levels test high. Irregular margins, taller-than-wide shapes, and vascularity are also more commonly found in cancerous thyroid nodules.

Doctors may identify thyroid nodules during imaging tests for another condition. In some cases, your doctor might feel a lump during a physical exam.

After your doctor identifies a thyroid nodule, they may perform a fine needle aspiration biopsy. They can also use molecular testing, radioiodine scans, and blood tests.

If your nodules are benign or too small for a biopsy, they should be monitored every 6 to 12 months with ultrasounds. Your doctor will also examine at your annual physical exam.

Thyroid nodules may require surgical removal, depending on how they grow or if they develop suspicious features.

Most thyroid nodules are benign and can be monitored without needing surgery.

When a thyroid nodule is related to thyroid cancer, your outlook can vary depending on the type of cancer and how advanced it is. Your age can also factor into the outlook.

Two forms of cancer that thyroid nodules can be associated with are papillary thyroid cancer and follicular thyroid cancer:

  • Papillary thyroid cancer: If this cancer has not spread to other portions of the body, it has a very low mortality rate.
  • Follicular cancer: This form of cancer occurs more often in older individuals and is more aggressive. As a result, follicular cancer tends to spread to other parts of the body more frequently and is more likely to be fatal.

Prompt surgical treatment of malignant thyroid nodules is associated with better outcomes.

You should notify your doctor if you:

  • notice a lump or unusual swelling in your neck
  • have difficulty swallowing or breathing
  • have been exposed to radiation
  • notice signs of a thyroid disorder like weight fluctuations, fatigue, or mood issues

Thyroid nodules are abnormal cell growths in the thyroid gland. They frequently have no symptoms, and a person may only receive a diagnosis after undergoing medical imaging for another condition.

It’s important to let your doctor know if you notice any lumps or unusual swelling in your neck. Most thyroid nodules are benign, but it’s important to monitor them for growth or suspicious changes. If a thyroid nodule is malignant, treatment will typically include surgery.