Thyroid gland cancer is a cancer which originates in the cells of the thyroid gland. Thyroid is a gland which is shaped like a butterfly and is situated at the base of the neck, below Adam's apple. The thyroid gland produces hormones which help in regulating blood pressure, heart rate, temperature of the body and your weight.
Thyroid cancer is not that common in the United States; however, its incidence seems to be increasing of late.
Majority of the patients suffering from thyroid cancer can be treated easily with chemotherapy, radioactive iodine, thyroid hormone therapy, external radiation therapy and surgery.
Types of Thyroid Gland Cancer
- Papillary Thyroid Cancer: This is the most common type of thyroid cancer and constitutes for about 80% thyroid cancer cases.
- Follicular Thyroid Cancer: This type includes Hurthle cell cancer.
- Medullary Thyroid Cancer: This type of thyroid cancer can be related with inherited genetic syndromes which involve tumors in other glands. However, majority of the medullary thyroid cancers are intermittent and usually are not related with inherited genetic syndromes.
- Anaplastic Thyroid Cancer: This is a rare type of thyroid cancer and is very aggressive; and hence difficult to treat.
- Thyroid Lymphoma: This type of thyroid cancer starts in the thyroid's immune system cells and is quite rare.
Causes of Thyroid Gland Cancer
The cause of thyroid cancer is not clear. It is believed that genetic changes or mutations in the thyroid cells cause the cancer. Due to the mutation, the cells grow and multiply at great speed. These cells also continue to live on instead of dying like normal cells. The buildup of the abnormal thyroid cells result in formation of a tumor. These abnormal cells infiltrate the nearby tissue and metastasize throughout the body.
Risk Factors for Thyroid Gland Cancer
- Exposure to large doses of radiation to the head and neck or from other sources, such as weapons testing and nuclear power plant accidents, increases the risk of developing thyroid cancer.
- Goiter is a noncancerous condition in which the thyroid gets enlarged. Having this condition also increases the risk of developing thyroid cancer.
- There are certain inherited genetic syndromes, such as multiple endocrine neoplasia, familial medullary thyroid cancer and familial adenomatous polyposis, increases the risk of developing thyroid cancer.
Signs and Symptoms of Thyroid Gland Cancer
- Appearance of a lump which can be felt on the neck through the skin.
- Changes in the voice, such as hoarseness.
- Patient also has difficulty in swallowing.
- Patient also experiences pain in the throat and neck.
- There is swelling in the lymph nodes of the neck.
Investigations for Thyroid Gland Cancer
- A physical exam is done on the neck to check for any lumps and lymph node swelling.
- Blood tests are done including a test which measures the level of TSH (thyroid-stimulating hormone) in the body.
- Imaging tests like ultrasound of the neck are done to determine the nature of the lump and also to check for enlarged lymph nodes.
- Ultrasound-guided needle biopsy is done to remove cells from the thyroid and to examine them with the help of a microscope so as to detect cancer cells.
Treatment for Thyroid Gland Cancer
Treatment depends on the type of bone cancer, the stage of the cancer and patient's general health. Treatment options comprise of chemotherapy, radiation, surgery or a combination of all. With treatment, majority of thyroid cancer patients can be cured.
Surgery for Thyroid Gland Cancer
Many patients suffering from thyroid cancer have to undergo surgery to either remove the entire or most of the thyroid gland. Surgeries done to treat thyroid cancer are:
- Thyroidectomy: This comprises of removing the entire or majority of the thyroid. The most common treatment for thyroid cancer is surgery to remove the entire thyroid.
- The surgeon after removing the thyroid may also remove the enlarged lymph nodes in the neck and send them for further testing for cancer cells.
Thyroid Hormone Therapy for Thyroid Gland Cancer
This therapy is done after the surgery for thyroid cancer. Patient is instructed to take thyroid hormone medications such as levothyroxine (Synthroid, Levothroid etc.) for life. This medicine helps in two ways. One is by supplying the missing hormone which the thyroid normally produces. Second is by suppressing the production of TSH (thyroid-stimulating hormone) from the pituitary gland, as high levels of TSH may encourage the growth of the remaining cancer cells.
Radioactive Iodine for Thyroid Gland Cancer
This treatment with radioactive iodine involves using large doses of radioactive iodine. Radioactive iodine treatment is commonly used after thyroidectomy surgery to kill any minute areas of thyroid cancer which were not removed during surgery. Radioactive iodine treatment is also used for treating recurring thyroid cancer after treatment or that cancer which metastasizes to other regions of the body.
Radioactive iodine treatment is done via a capsule form or liquid which the patient can swallow. The radioactive iodine is absorbed mainly by thyroid cells and thyroid cancer cells, so there is very little chance of harming the other cells in the body.
Side Effects Of Radioactive Iodine Are: Dry mouth and eyes, nausea, changes in taste or smell, pain felt where the thyroid cancer cells have metastasized like in chest or neck.
The majority of the radioactive iodine exits the body via urine in the initial few days after commencement of treatment. During this time you have to avoid close contact with others, particularly pregnant women and children, so as to avoid radiation exposure to them.
External Radiation Therapy for Thyroid Gland Cancer
External radiation therapy is done with the help of a machine which aims high-energy beams at specific points on the body. This treatment is also known as External Beam Radiation Therapy and is usually given for some minutes at a time and for five days in a week, for around six weeks. External radiation therapy is often used for treating thyroid cancer which has metastasized to the bones.
Chemotherapy for Thyroid Gland Cancer
Chemotherapy is a treatment which involves the use of drugs/ chemicals to destroy cancer cells. Chemotherapy is often given intravenously so that it can travel throughout your body, thus destroying the rapidly growing cells and cancer cells.
Although chemotherapy is not used that much for treating thyroid cancer, but it is helpful for those patients who are not benefitting from other types of therapies.