The thyroid is a butterfly shaped gland located at the base of the throat. It has two lobes separated in the middle by a strip of tissue (the isthmus). The thyroid itself secretes three main hormones: (1) Thyroxine contains iodine, needed for growth and metabolism; (2) Triiodothyronine, similar in function to Thyroxine, effects body size, tissues growth, and function: and (3) Calcitonin, which decreases the concentration of calcium in the blood and increases calcium in the bones. All three of these hormones have an important role in your child’s growth. Pediatric thyroid cancer is the third most common tumor malignancy in children. It occurs six times more often in females than males and shares several characteristics with adult thyroid cancer patients. Surgery is the preferred treatment for this cancer and although the procedure is often uncomplicated, one of the risks of thyroid surgery involves vocal cord paralysis. Consequently, an otolaryngologist—head and neck surgeon should be consulted.
Types of thyroid cancer in children:
Papillary: This form of thyroid cancer occurs in cells that produce thyroid hormones containing iodine. This type, the most common form of thyroid cancer in children, grows very slowly.
Follicular: This type of thyroid cancer also develops in cells that produce thyroid hormones containing iodine. The disease afflicts a slightly older age group and is less common in children. This type of thyroid cancer is more likely to spread to the neck via blood vessels causing the cancer to spread to other parts of the body, making the disease difficult to control.
Medullary: This rare form of thyroid cancer develops in cells that produce calcitonin, a hormone that does not contain iodine. This cancer tends to spread to other parts of the body and constitutes about 5-10 percent of all thyroid malignancies. Medullary thyroid carcinoma (MTC) in the pediatric population is usually associated with multiple endocrine neoplasia type 2 (MEN2), an inherited genetic form of the cancer.
Anaplastic: This is the fastest growing of the thyroid cancers, with extremely abnormal cells that grow and spread rapidly, especially locally in the head and neck region. This form of cancer usually is found in older patients.
Symptoms:
The symptoms of this disease vary. Your child may have a lump in the neck, continuous swollen lymph nodes, a tight or full feeling in the neck, and/or trouble with breathing or swallowing, hoarseness.
Diagnosis:
If any of these symptoms occur, consult your child’s physician for a diagnosis. The diagnosis could consist of a head and neck examination to determine if unusual lumps are present; a blood test to indicate how the thyroid is functioning; a sonography, which uses high-frequency sound waves and a computer to create an image of the thyroid gland; a radioactive iodine scan, which provides information about the thyroid shape and function, identifying areas in the thyroid that do no absorb iodine in the normal way; fine needle biopsy, removal for study of a small part of the tumor; and surgery, where a procedure known as a thyroid lobectomy, necessitates removal of the lobe of the thyroid gland that contains the tumor, for analysis.
Treatments for thyroid cancer:
If the tumor is found to be malignant then surgery is used to remove as much of the tumor as possible either by lobectomy or subtotal thyroidectomy (removal of at least one thyroid lobe and up to a near-total removal of the thyroid gland). If necessary, the otolaryngologist— head and neck surgeon may remove the entire thyroid, in a procedure called a total thyroidectomy. Surgery may be followed by radioactive iodine therapy which destroys cancer cells that are left after surgery and help prevent the disease from returning Thyroid hormone therapy may need to be administered throughout your child’s life when he/she has had surgery to remove the thyroid followed by radioactive iodine treatment to replace normal hormones and slow the growth of cancer cells. If cancer has spread to other parts of the body, chemotherapy, the treatment of disease by means of chemical substances or drugs, may be given. This therapy interferes with the cancer cell’s ability to grow or reproduce. Different groups of drugs work in different ways to fight cancer cells and shrink tumors. In general, treatment outcomes for this type of cancer in children tend to be excellent. The best outcome is achieved with teenage girls, papillary type cancer, and a tumor localized to the thyroid gland.
Source: National Cancer Institute “Population-based Outcomes for Pediatric Thyroid Carcinoma,” by Nina L. Shapiro MD, and Neil Bhattacharyya MD, Laryngoscope. 2005 Feb;115(2):337-40.
Frequently Asked Questions
The thyroid gland produces three main hormones: Thyroxine, which contains iodine and is vital for growth and metabolism; Triiodothyronine, which affects body size, tissue growth, and function similar to Thyroxine; and Calcitonin, which lowers blood calcium levels and increases calcium storage in bones. These hormones play essential roles in a child's growth and development.
There are four main types of thyroid cancer in children: Papillary, the most common and slow-growing; Follicular, less common and more likely to spread through blood vessels; Medullary, rare and associated with an inherited genetic condition called MEN2; and Anaplastic, which is very aggressive but usually found in older patients. Each type affects different thyroid cells and varies in growth and spread.
Symptoms can include a lump in the neck, continuously swollen lymph nodes, a tight or full feeling in the neck, difficulty breathing or swallowing, and hoarseness. Because symptoms vary, any persistent or unusual neck changes should prompt consultation with a pediatrician or specialist for proper evaluation.
Diagnosis involves a head and neck exam to check for lumps, blood tests to assess thyroid function, sonography to image the gland, radioactive iodine scans to evaluate thyroid activity, fine needle biopsy to sample tumors, and sometimes surgery to remove part of the thyroid for analysis. These combined approaches help determine if a tumor is malignant and guide treatment.
Treatment primarily involves surgery to remove the tumor via lobectomy, subtotal, or total thyroidectomy depending on tumor size and spread. Post-surgery, radioactive iodine therapy may be used to destroy remaining cancer cells, and lifelong thyroid hormone therapy might be necessary to replace hormones and inhibit cancer growth. Chemotherapy could be recommended if the cancer has spread beyond the thyroid.
One significant risk of thyroid surgery is vocal cord paralysis, which can affect voice and breathing. Therefore, surgeries are performed by otolaryngologists specializing in head and neck procedures to minimize complications and ensure better outcomes for pediatric patients.
Pediatric thyroid cancer generally has excellent treatment outcomes, especially in cases with papillary type cancer localized to the thyroid gland. Teenage girls tend to have the best prognosis. These outcomes are often better than in adults, partly due to differences in tumor behavior and treatment response in children.
