Are Thyroid Nodules Common in Kids?

Thyroid nodules are not very common in children. Most of the time, thyroid nodules are benign (not cancerous). It is estimated that more than 75% of thyroid nodules found in children and teenagers are benign.

The thyroid is a butterfly-shaped endocrine gland located below the Adam's apple in the lower part of the neck that wraps around the windpipe (trachea). It produces hormones that help the body use energy, maintain body temperature, and keep the heart, brain, muscles, and other organs functioning properly.

In kids, thyroid hormone helps ensure normal growth and development and that the child’s energy, metabolism, heart, muscles, and other organs function as they should.

A thyroid nodule is an abnormal growth of cells that forms a lump within the thyroid gland. 

While thyroid nodules are common in adults, especially as they age, nodules are much less common in children. Most of the time, thyroid nodules are benign (not cancerous). It is estimated that more than 75% of thyroid nodules found in children and adolescents are benign.

Most of the time, thyroid nodules don’t cause any symptoms. Sometimes a patient will discover a lump in the neck which can lead to a diagnosis. 

Most thyroid nodules, even cancerous ones, are non-functioning, and thyroid tests will be normal. 

Symptoms of thyroid nodules occur rarely and may include: 

• Pain in the neck, jaw, or ear
• Difficulty breathing or swallowing, or a “tickle” in the throat, if a nodule is large enough to compress the windpipe or esophagus
• Hoarseness if the nodule invades the nerve that controls the vocal cords (usually related to thyroid cancer)

It is unknown what causes thyroid nodules in most cases. 

Risk factors for developing thyroid nodules include: 

• Exposure to radiation (most commonly medical radiation used to treat another form of cancer)
• A family history of thyroid nodules or thyroid cancer
• Iodine deficiency (uncommon in the United States)

Thyroid nodules are often found incidentally during routine physical exams or on imaging tests done for unrelated reasons. Sometimes, patients notice a lump in their neck that leads to a diagnosis. In some cases, abnormal thyroid function tests may cause a thyroid nodule to be found. 

Once a thyroid nodule is discovered, it is necessary to determine if it is benign (not cancer) or malignant (cancer).

In addition to a medical history and physical examination of the thyroid and the neck, blood tests are done to determine levels of thyroid hormone (T4, thyroxine) and thyroid-stimulating hormone (TSH). However, these tests and results alone are not enough to determine whether thyroid nodules are cancerous or not. 

Other tests used to confirm whether a thyroid nodule is benign or cancerous include: 

• Thyroid ultrasound 
• Fine needle aspiration (FNA) biopsy 
• Nuclear thyroid scan

If thyroid nodules are benign, they usually do not need to be removed, but a follow-up ultrasound is recommended 6 to 12 months later to see if the nodule grows or changes. 

Surgical removal of nodules in children and adolescents is usually recommended if: 

• The nodules are very large (more than 3 to 4 cm across) 
• They produce excess thyroid hormone (“hot nodules”) 
• The nodule impacts quality of life, even if it seems benign on a FNA biopsy
  • In about 25% of patients, FNA results do not clearly determine if a nodule is benign or malignant

More than 90% of thyroid cancers in children are papillary thyroid cancer, which is a type of thyroid cancer that grows slowly and is rarely fatal. 

Treatment for thyroid cancer involves one or more of the following:

• Surgery to remove the cancer
• Radioactive iodine (“radioiodine therapy”) 
• Thyroid hormone 
• External-beam radiation therapy 
• Chemotherapy