Thyroid cancer occurs when malignant cells develop in the tissues of the thyroid gland.
This is different from the nodules that can appear in this gland, which are usually benign.
The thyroid is a butterfly-shaped gland located in the lower part of the throat, near the windpipe. It is slightly larger than a US quarter.
This gland uses iodine, a mineral that is present in certain foods and enriched salt, to produce several hormones that perform key functions in the body:
- They control heart rate, body temperature, and metabolism (the rate at which food is converted into energy)
- Monitor blood calcium balance
Thyroid cancer is mainly divided into two types, depending on where it forms.
Differentiated thyroid cancer, which is divided into:
- Well differentiated, papillary or follicular, highly treatable and curable
- Poorly differentiated and undifferentiated (anaplastic). This type of thyroid cancer spreads quickly and is more difficult to treat. Its recovery rate is low. People diagnosed with this form of cancer should have a molecular test to detect a BRAF gene mutation.
Medullary thyroid cancer, a type of neuroendocrine cancer that begins in the T cells of the thyroid. These are the cells that help maintain a healthy balance of calcium in the blood. It is usually very treatable and can often be cured with surgery; and in certain cases with radioactive iodine.
Thyroid cancer usually begins as a small lump in the thyroid gland. There may also be a swelling of the lymph nodes in the neck. As a result, symptoms can include:
- Swelling of the neck
- Breathing problems due to narrowing of the airways
- Coughing up blood
- Diarrhea due to high calcitonin level
Incidence and risk factors
Thyroid cancer affects women more often than men and usually occurs between the ages of 25 and 65. Among the most frequent risk factors are:
- Family history of thyroid disease or multiple endocrine neoplasia syndrome.
- Mutation in the RET gene
- History of goiter
- Female gender
- Being asian
Diagnostic evaluation and staging
The following tests and procedures may be used for the diagnosis and staging of thyroid cancer:
- Physical exam and family history
- Hormonal studies of the blood
- Biochemical studies of blood
- Computed tomography
- Fine needle aspiration biopsy
Treatment consists of surgical removal of the thyroid gland and surrounding lymph nodes.
Further treatment will depend on the calcitonin levels. A further increase in the level of calcitonin may indicate a new growth of the cancer. What’s more:
- Chemotherapy and radiation do not work very well for this type of cancer.
- Radiation is used in some people after surgery.
- New targeted therapies can also reduce tumor growth.
You need to have a good treatment plan with your doctor.
In 2020, there were 52,890 thyroid cancer diagnoses in the United States, and about 2,180 deaths. The 5-year survival rate (how many people live five years after being diagnosed) is 98.3%.
Globally, thyroid cancer has been increasing, up to 20%, and is attributed to factors ranging from increased detection to a high prevalence of modifiable environmental and lifestyle factors.
Sources: cancer.gov, American Cancer Society, CDC, American Thyroid Association, MedlinePlus.