What is thyroid cancer?
Thyroid cancer occurs in the cells of the thyroid, a butterfly-shaped gland situated at the base of your neck, just below Adam’s apple. Your thyroid makes hormones that regulate your heart rate, blood pressure, body infection, and weight. This may not cause any symptoms at first. But as it grows, it can cause pain and swell in the neck.
There are several types of thyroid cancer. Some grow very slowly and others can be very violent. Most belongings of this disease can be cured with treatment. These disease rates appear to be increasing. Some doctors believe this is because new technology allows them to find small thyroid cancers that may not have been found in the past.
Types of thyroid cancer
- Papillary thyroid cancer: This disease, arises from follicular cells, which crop and store thyroid hormones. Papillary thyroid cancer can occur at any age, but most often affects people in their 30s to 50s. Doctors sometimes refer to papillary and follicular thyroid cancer collected as differentiated thyroid cancer.
- Follicular thyroid cancer: This also arises from the follicular cells of the thyroid. It usually affects societies over the age of 50. Hürthle cell cancer is a rare and potentially more aggressive type of follicular thyroid cancer.
- Anaplastic thyroid cancer: This is a rare type of thyroid cancer that begins in follicular cells. It grows quickly and is very difficult to treat. This usually occurs in adults 60 years of age or older.
- Medullary thyroid cancer: This begins in thyroid cells called C cells, which make the hormone calcitonin. Raised levels of calcitonin in the blood can specify medullary thyroid cancer at a very early stage. Certain genetic syndromes increase the risk of medullary thyroid cancer, although this genetic link is rare.
- Other rare types: Other very rare types of diseases that begin in the thyroid include thyroid lymphoma, which begins in cells of the thyroid immune system, and thyroid sarcoma, which begins in cells of the thyroid’s connective tissue.
Symptoms of thyroid cancer
Thyroid cancer does not usually cause any signs or symptoms early in the disease. As thyroid cancer grows, it can cause:
- A lump (nodule) that can be felt through the skin on the neck
- Changes in your voice, including increased hoarseness
- Difficulty to swallow
- Pain in the neck and throat
- Swollen lymph nodes in your neck
Causes of thyroid cancer
It is not clear what causes thyroid cancer.
Thyroid cancer occurs when cells in your thyroid feel inherited changes (mutations). Mutations allow cells to grow and multiply rapidly. Cells also lose the aptitude to die, as normal cells would. The accumulation of abnormal thyroid cells forms a tumour. The abnormal cells can invade nearby tissue and spread (metastasize) to other parts of the body.
Factors that can escalation your risk of thyroid cancer include:
- Gender: This disease happens more often in females than in men.
- Exposure to high levels of radiation: Radiation therapy treatments to the head and neck intensification the risk for this disease.
- Certain inherited genetic syndromes: Genetic syndromes that increase the risk of thyroid cancer contain familial medullary thyroid cancer, numerous endocrine neoplasia, Cowden syndrome, and familial adenomatous polyposis.
Diagnosis of thyroid cancer
Tests and processes used to diagnose thyroid cancer include:
- Physical exam: Your doctor will observe your neck to feel for physical changes in your thyroid, such as thyroid nodules. They may also ask you about your risk factors, such as past radiation exposure and a family history of thyroid tumours.
- Blood test: Blood tests help determine if the thyroid gland is working normally.
- Ultrasound images: Ultrasound uses high-frequency sound waves to create images of body structures. To create an image of the thyroid, the ultrasound transducer is placed on the lower part of the neck. The arrival of your thyroid on ultrasound helps your doctor determine if a thyroid nodule is likely not cancerous (benign) or if there is a risk that it is cancerous.
- Removal of a sample of thyroid tissue: During a fine needle aspiration biopsy, your doctor inserts a long, thin needle through the skin to the thyroid nodule. Ultrasound imaging is typically used to precisely guide the needle to the nodule. Your specialist uses the needle to eliminate samples of suspicious thyroid tissue. The sample is tested in the laboratory to look for cancer cells.
- Other imaging tests: You may have one or more imaging tests to help your doctor find out if your disease has spread beyond the thyroid. Imaging tests can include CT, MRI, and nuclear imaging tests that use a radioactive form of iodine.
- Genetic test: Some people with medullary thyroid cancer may have genetic changes that may be associated with other endocrine cancers. Your family history may lead your doctor to recommend genetic testing to look for genes that increase your risk of cancer.
Treatment for thyroid cancer
Your thyroid cancer treatment options depend on the type and stage of your disease, your general health, and your preferences. Most thyroid cancers can be cured with treatment.
Treatment may not be needed right away
Very small thyroid cancers that have a low risk of spreading throughout the body may not need treatment right away. Instead, you might consider active surveillance with frequent cancer monitoring. Your doctor may recommend blood tests and an ultrasound exam of your neck once or twice a year.
In some people, cancer may never grow and never require treatment. In others, eventually, growth can be detected and treatment can be started.
Most people with thyroid cancer have surgery to remove the thyroid. Which operation your doctor may recommend depends on the type of this disease, the size of the disease, whether the disease has spread beyond the thyroid, and the results of an ultrasound exam of the entire thyroid gland.
Operations used to treat thyroid cancer includes:
- Removal of all or utmost of the thyroid (thyroidectomy): An operation to remove the thyroid gland may involve removing all of the thyroid tissue (total thyroidectomy) or most of the thyroid tissue (near-total thyroidectomy). The surgeon often leaves small borders of thyroid tissue around the parathyroid glands to reduce the risk of damage to the parathyroid glands, which help regulate calcium levels in the blood.
- Removal of a portion of the thyroid (thyroid lobectomy): During a thyroid lobectomy, the surgeon eliminates half of the thyroid. It might be recommended if you have slow-growing thyroid cancer in one part of the thyroid and there are no suspicious nodules in other areas of the thyroid.
- Removal of the lymph nodes in the neck (lymph node dissection): By removing the thyroid, the surgeon can also remove nearby lymph nodes in the neck. These can be tested for signs of cancer.
- There is also a risk that the nerves connected to the vocal cords may not function normally after surgery, which can lead to vocal cord paralysis, hoarseness, voice changes, or shortness of breath. Treatment can improve or reverse nerve problems.
Thyroid hormone therapy
This medication has two benefits: it supplies the missing hormone that the thyroid would normally produce, and it suppresses the production of thyroid-stimulating hormone (TSH) from the pituitary gland. High levels of TSH could stimulate the growth of the remaining cancer cells.
Radioactive iodine treatment uses large doses of a form of iodine that is radioactive.
Radioactive iodine treatment is frequently used after thyroidectomy to destroy any residual healthy thyroid tissue, as well as microscopic areas of this disease that were not removed during surgery. Radioactive iodine treatment can also be used to treat thyroid cancer that comes back after treatment or has spread to other areas of the body.
Side effects can include:
- Dry mouth
- Mouth pain
- Eye inflammation
- Altered sense of taste or smell
Most of the radioactive iodine leaves your body in your urine during the first few days after treatment. You will be given instructions on the precautions to take during this time to protect others from radiation. For example, you may be asked to temporarily avoid close contact with other people, especially children, and pregnant women.
External radiation therapy
Radiation therapy can also be delivered externally by a machine that directs high-energy beams, such as x-rays and protons, to precise points on the body (external beam radiation therapy). During treatment, you lie still on a table while a machine changes about you.
Chemotherapy is a drug treatment that uses chemicals to destroy cancer cells. Chemotherapy is usually given as an infusion through a vein. The chemicals travel throughout the body and destroy rapidly growing cells, including cancer cells.
Targeted drug therapy
Targeted drug treatments focus on specific abnormalities present in cancer cells. By delaying these abnormalities, targeted drug treatments can reason cancer cells to die.
Injecting alcohol into cancers
Alcohol ablation involves injecting alcohol into small thyroid cancers using imaging such as ultrasound to ensure accurate injection placement. This procedure causes thyroid cancers to shrink.
Supportive (palliative) care
Palliative care is specialized medical care that focuses on providing relief from pain and other symptoms of a serious illness. Palliative care specialists work with you, your family, and your other doctors to provide an additional layer of support to complement your ongoing care.
Despite treatment, thyroid cancer can return, even if your thyroid has been removed. This could happen if microscopic disease cells spread beyond the thyroid before being removed.
This disease can come back in:
- Lymph nodes in the neck
- Small pieces of thyroid tissue that remain during surgery
- Other areas of the body, such as the lungs and bones
Thyroid cancer that comes back can be treated. Your doctor may recommend regular blood tests or thyroid scans to check for signs of this disease recurrence.
Doctors aren’t sure what causes most thyroid cancer, so there is no way to prevent this disease in people who are at average risk for the disease.
Prevention for people at high risk
Adults and kids with an inherited genetic transformation that increases the risk of medullary thyroid cancer may consider thyroid surgery to prevent the disease (prophylactic thyroidectomy). Discuss your options with a genetic counsellor who can explain your risk for thyroid cancer and your treatment options.
Prevention for people close to nuclear power plants
Sometimes a drug that blocks the effects of radiation on the thyroid is given to people who live near nuclear power plants. The drug (potassium iodide) could be used in the unlikely event of a nuclear reactor accident. If you live within 10 miles of a nuclear power plant and are concerned about safety precautions, contact your local or state emergency management department for more information.
Departments to consult for this condition
- Department of oncology