Thyroid cancer arises from the cells of the thyroid gland.
Thyroid cancer arises from the cells of the thyroid gland. The thyroid is a butterfly-shaped gland located in the front of the neck, just below Adam's apple. The thyroid gland produces hormones (chemicals acting as messengers in the body) that regulate body weight, temperature, blood pressure and heart rate. Thyroid cancer is classified based on the type of cells present in the tumor. The treatment and prognosis depend on the type of thyroid cancer.
How is thyroid cancer diagnosed?
The physician performs a complete clinical assessment. Complete blood analysis and radiological tests are performed (ultrasound, computed tomography [CT], magnetic resonance imaging [MRI] and radioactive iodide imaging). Genetic testing may be done if genetic syndromes (such as familial adenomatous polyposis or FAP) are suspected. A biopsy can help confirm the diagnosis and identify the type of thyroid cancer. A biopsy is a minimally invasive procedure that involves obtaining a small sample of thyroid tissue with the help of a needle and then studying it under a microscope.
What are the signs and symptoms of thyroid cancer?
The common signs and symptoms of thyroid cancer include
- Swelling in the front of the neck, which is painless initially
- Difficulty swallowing
- Difficulty breathing due to compression of the trachea (windpipe)
- Change in voice
- Cough
- Weight loss
- Palpitations
What causes thyroid cancer?
The exact cause of thyroid cancer is unknown, but various factors increase the risk of thyroid cancer. The common risk factors include
- Genetic predisposition and certain genetic syndromes, such as familial medullary thyroid cancer, multiple endocrine neoplasia, familial adenomatous polyposis and Cowden syndrome
- History of breast cancer
- Female sex
- Radiation exposure because of cancer treatment, occupation or its presence in the environment
- Age: Thyroid cancer is more common in those who are older than 40 years of age. The peak age group for thyroid cancer in women is generally between 40 to 50 years. Males are generally diagnosed in the age of 60 to 70 years.
How is thyroid cancer treated?
The treatment may involve one or a combination of multiple treatment modalities, which depend on the extent and type of cancer.
The treatment options include
- Surgery: It may involve removing all (total thyroidectomy) or most of the thyroid (near-total thyroidectomy). Removal of lymph nodes in the neck (lymph node dissection) may or may not be performed.
- Thyroid hormone therapy: After thyroidectomy surgery, thyroid hormone medication needs to be taken for a lifetime to maintain thyroid hormone levels.
- Radioactive iodine: Radioactive iodine treatment uses large doses of radioactive iodine. It is usually used after surgery. It destroys the remaining thyroid tissue and microscopic thyroid cancer. Most of the radioactive iodine is excreted in the urine a few days after treatment.
- External radiation therapy: This therapy targets and selectively kills cancer cells and shrinks tumors using radiation.
- Chemotherapy: Chemotherapy is a drug treatment given intravenously (IV) that uses chemicals to kill cancer cells.
- Targeted drug therapy: Targeted drug treatments focus on specific abnormal proteins in cancer cells. The drugs block the abnormalities and kill cancer cells.
- Injecting alcohol into cancers: Alcohol ablation involves injecting small thyroid cancers with alcohol using radiological guidance. This shrinks thyroid cancer.
- Palliative (supportive) care: This is specialized medical care that focuses on providing relief from pain and other serious symptoms.