What is a thyroid nodule?
A thyroid nodule is a firm lump in the thyroid gland, which is located in the front of the neck. Depending on the size and location, the nodule may or may not be visible or palpable (touched or felt) on exam. A thyroid nodule may be cancerous or benign (not cancerous). The majority of thyroid nodules in both children and adults are benign.
Causes of thyroid nodules
While we don’t fully understand why children and adolescents develop thyroid nodules, there are several factors that increase the risk of being diagnosed with a thyroid nodule. These include:
- Age: The risk of developing a thyroid nodule increases with age
- Gender: Females are at increased risk of developing thyroid nodules compared to males
- Family history of thyroid disease (thyroid nodules or thyroid cancer)
- Personal history of thyroid disease
- Radiation exposure: Both environmental (rare) and medical exposure to radiation, for evaluation and treatment (for example, a previous history of cancer that was treated with ionizing radiation)
- Iodine insufficiency (iodine is needed for the production of thyroid hormone)
Testing and diagnosis
Historically, thyroid nodules in children have been most frequently discovered on physical exam by a parent, teacher, dentist, primary care provider, patient or friend. With the increased use of radiologic studies, more nodules are discovered incidentally (by chance) during an unrelated radiologic exam, such as a head and neck CT scan, MRI or ultrasound.
In the Pediatric Thyroid Center at Children’s Hospital of Philadelphia, we have established a unique evaluation process for all suspected thyroid nodules that ensures the most accurate diagnosis and appropriate treatment for your child. Our goal is to eliminate the potential for re-treatment as a result of surgeries that were done without prior consultation from a thyroidologist.
If your child's doctor suspects a thyroid nodule, a complete evaluation may include:
- History and physical exam, including a complete evaluation of the thyroid and the lymph nodes in the neck. Watch CHOP Endocrinologist Andrew J. Bauer, MD, perform a pediatric thyroid exam.
- Blood test to measure the thyroid-stimulating hormone (TSH) level to find out how well the thyroid is working.
- Thyroid ultrasound (or thyroid scan) to learn about the size, number, appearance and location of the nodule(s).
- Nuclear medicine uptake and scan should only be ordered if the TSH is low or suppressed. A thyroid uptake and scan determines how well the thyroid tissues absorb iodine. In patients with a normal TSH, an uptake and scan does not help determine if the nodule is benign or cancerous. If the TSH is suppressed, an uptake and scan helps confirm if the nodule is functioning on its own, which means there is a lower risk of cancer.
For the majority of children, enlarged lymph nodes are due to infection (recent cold, sore throat or ear infection), dental issues (losing teeth, teeth coming in or cavities) or, in teenagers, acne. Often, primary care physicians will treat the suspected infection with one course of antibiotics. This is a reasonable plan; however, if the lymph nodes do not reduce in size over six to eight weeks, appear to be getting larger or more become visible or palpable, your child's doctor should consider ordering a thyroid and neck ultrasound before referring your child to a surgeon.
If a thyroid nodule is found associated with these lymph nodes, your child may be referred to a program that specializes in the diagnosis and treatment of thyroid disorders, such as the Pediatric Thyroid Center at CHOP. In addition to a connection between thyroid nodules and enlarged lymph nodes, enlarged lymph nodes are a common finding with autoimmune thyroid disease, both hypothyroidism and hyperthyroidism.
Depending on your child's medical history, physical exam and ultrasound findings, a fine-needle aspiration (FNA) may be recommended in order to collect cells to examine under the microscope. During an FNA, a very thin needle is used to extract a sample of cells from a thyroid nodule(s) and/or lymph nodes to be analyzed.
Treatment for thyroid nodules
At CHOP, experts at the Pediatric Thyroid Center take a team approach to treatment for children with thyroid nodules. Our board-certified endocrinologists, pediatric surgeons and nurses collaborate to provide your child with individualized care and the best possible outcome.
Our Center is led by Andrew J. Bauer, MD, a world-renowned endocrinologist and researcher, who is often sought for second opinions on difficult-to-diagnose thyroid disorders. Dr. Bauer is a member of the American Thyroid Association (ATA) and co-chaired an international ATA task force that created the first guidelines for evaluating and managing thyroid nodules and thyroid cancer in children.
Treatment for your child’s thyroid nodule will depend on whether it is benign (not cancerous), malignant (cancerous) or undetermined, and can range from regular monitoring to surgery. The majority of thyroid nodules are not cancerous.
Benign thyroid nodules
The use of fine-needle aspiration (FNA) has allowed benign (not cancerous) nodules to be followed without surgery in children and adolescents. Most benign nodules remain the same size, even over long periods of time. If your child’s thyroid nodule grows, clinicians may recommend a second FNA, repeat ultrasounds and/or surgery to remove half of the thyroid gland (lobectomy).
Malignant thyroid nodules
If results of your child’s FNA show malignant cells (cancerous), the next step is to arrange for surgical removal of the entire thyroid gland, a procedure called total thyroidectomy. The most common diagnosis in this category is papillary thyroid cancer (PTC).
See differentiated thyroid cancer for a complete discussion of evaluation and treatment.
Indeterminate thyroid nodules
While most thyroid nodules can be classified as benign or malignant, about 25-30 percent fall into a third group — indeterminate thyroid nodules. Cells that fall into this group include:
- Follicular lesions of undetermined significance (FLUS)
- Follicular neoplasms (FN)
- Suspicious for malignancy, in which the final diagnosis can only be established by close examination of the entire nodule under a microscope.
In adults, there are several tests that can help determine if the indeterminate cells are benign or malignant. Some of these tests are now being used in children and adolescents.
The risk of an indeterminate thyroid nodule eventually being discovered as cancerous depends on the type of cell category:
- Follicular lesions of undetermined significance (FLUS): 5-15 percent
- Follicular neoplasms (FN): 15-30 percent
- Suspicious for malignancy: 60-75 percent
The most common diagnoses in the indeterminate group are:
- Follicular adenoma (FA): non-cancerous nodule
- Follicular thyroid carcinoma (FTC): cancerous nodule
- Follicular variant of papillary thyroid cancer (fvPTC): cancerous nodule
Follicular adenoma (FA) and follicular thyroid carcinoma (FTC)
The cell features between follicular adenoma (FA) and follicular thyroid carcinoma (FTC) are nearly the same, so a fine-needle aspiration will not help provide a final answer. The only way to find out if the nodule is cancerous or not is to take out the entire nodule for examination. This is performed though a lobectomy, surgical removal of half the thyroid gland.
If the cells are not cancerous, clinical follow-up will be arranged. For the majority of patients who undergo lobectomy, the remaining thyroid tissue will produce an adequate amount of thyroid hormone, and thyroid hormone replacement therapy will not be necessary.
For patients found to have a cancerous nodule, a second surgery (called a completion thyroidectomy) may be recommended to remove the remaining thyroid tissue.
Follicular variant of papillary thyroid cancer (fvPTC)
For follicular variant of papillary thyroid cancer (fvPTC), the cells from a fine-needle aspiration biopsy often look suspicious, but these lesions may have less concerning features and be initially classified as follicular lesions of undetermined significance (FLUS) or follicular neoplasms (FN). This is one of several reasons why surgical removal of a nodule, even those classified as FLUS, is recommended. The surgery to remove a thyroid nodule is called a lobectomy, which is the removal of half of the thyroid gland. The nodule is then examined and an exact diagnosis is made.
For patients who have had only half of the thyroid removed and are subsequently diagnosed with FTC or fvPTC, a second surgery may be performed to remove the remaining thyroid tissue. This procedure is called a completion thyroidectomy.
Suspicious for malignancy
For results that are described as "suspicious for malignancy," surgical removal of the entire thyroid (total thyroidectomy) is the most conservative approach, as approximately 60 to 75 percent of these nodules will ultimately be diagnosed as thyroid cancer.
See differentiated thyroid cancer for a complete discussion of evaluation and treatment.
When the FNA sample is insufficient
In rare situations, even with a highly skilled provider performing the procedure, the FNA sample may be “inadequate” for evaluation. The options after an inadequate sample are obtained include:
- Repeating the FNA. If the decision is to repeat the FNA, we may advise you to wait three to six months to allow for healing from the previous attempt.
- Close clinical observation. We will perform a repeat thyroid exam and ultrasound six months after the initial FNA. We will continue to monitor your child and may recommend a repeat FNA or surgery based on the results.
- Proceeding to surgery. For patients who elect to have surgery, the most common procedure is a lobectomy: removal of the portion of the thyroid gland containing the nodule(s). If there are nodules in both the right and left lobes, a total thyroidectomy (removal of the entire thyroid gland) may be recommended.
Follow-up care for thyroid nodules
Follow-up care for children with thyroid nodules will depend on whether the nodule was benign or malignant and what treatment was received.
While most children with benign thyroid nodules will not receive surgery, it is recommended they continue to be monitored. These children should receive a physical exam and ultrasound every 6-12 months, then decreasing in frequency if no changes are seen. If a nodule grows or develops in a way that is concerning on ultrasound, clinicians may recommend a repeated fine-needle aspiration to test the cells.
If your child received a lobectomy (removal of half of the thyroid gland), your child’s remaining thyroid tissue will likely produce an adequate amount of thyroid hormone. In most cases, thyroid hormone replacement therapy is not needed.
If your child received a total thyroidectomy (removal of all of the thyroid gland), they will need to take thyroid hormone replacement — a once-a-day medication — for medication for the rest of their life.
Follow-up care and ongoing support and services are available at our Main Campus and throughout our CHOP Care Network. Our team is committed to partnering with you to provide the most current, comprehensive and specialized care possible for your child.
Reviewed by Andrew J. Bauer, MD