Doctors often cannot explain why one person develops thyroid cancer and another does not. However, it is clear that no one can catch thyroid cancer from another person.
Research has shown that people with certain risk factors are more likely than others to develop thyroid cancer. A risk factor is something that may increase the chance of developing a disease.
Studies have found the following risk factors for thyroid cancer:
- Radiation: People exposed to high levels of radiation are much more likely than others to develop papillary or follicular thyroid cancer. One important source of radiation exposure is treatment with x-rays. Between the 1920s and the 1950s, doctors used high-dose x-rays to treat children who had enlarged tonsils, acne, and other problems affecting the head and neck. Later, scientists found that some people who had received this kind of treatment developed thyroid cancer.
- Family history of medullary thyroid cancer: Medullary thyroid cancer sometimes runs in families. A change in a gene called RET can be passed from parent to child. Nearly everyone with the changed RET gene develops medullary thyroid cancer. The disease occurs alone as familial medullary thyroid cancer or with other cancers as multiple endocrine neoplasia (MEN) syndrome.
- Family history of goiters or colon growths: A small number of people with a family history of having goiters (swollen thyroids) with multiple thyroid nodules are at risk for developing papillary thyroid cancer. Also, a small number of people with a family history of having multiple growths on the inside of the colon or rectum (familial polyposis) are at risk for developing papillary thyroid cancer.
- Personal history: People with a goiter or benign thyroid nodules have an increased risk of thyroid cancer.
- Being female: In the United States, women are almost three times more likely than men to develop thyroid cancer.
- Age over 45: Most people with thyroid cancer are more than 45 years old
- Most people with anaplastic thyroid cancer are more than 60 years old.
- Iodine: Iodine is a substance found in shellfish and iodized salt. Scientists are studying iodine as a possible risk factor for thyroid cancer. Too little iodine in the diet may increase the risk of follicular thyroid cancer. However, other studies show that too much iodine in the diet may increase the risk of papillary thyroid cancer. More studies are needed to know whether iodine is a risk factor.
Having one or more risk factors does not mean that a person will get thyroid cancer. Most people who have risk factors never develop cancer.
People with thyroid cancer have many treatment options. Treatment usually begins within a few weeks after the diagnosis, but you will have time to talk with your doctor about treatment choices and get a second opinion.
The choice of treatment depends on:
- the type of thyroid cancer (papillary, follicular, medullary, or anaplastic)
- the size of the nodule
- your age
- whether the cancer has spread
You and your doctor can work together to develop a treatment plan that meets your needs.
Surgery
Most people with thyroid cancer have surgery. The surgeon removes all or part of the thyroid. The type of surgery depends on the type and stage of thyroid cancer, the size of the nodule, and your age.
- Total thyroidectomy: This surgery can be used for all types of thyroid cancer. The surgeon removes all of the thyroid through an incision in the neck. If the surgeon is not able to remove all of the thyroid tissue, it can be destroyed by radioactive iodine therapy later.
- Nearby lymph nodes also may be removed. If cancer has invaded tissue within the neck, the surgeon may remove nearby tissue. If cancer has spread outside the neck, surgery, radioactive iodine therapy, or external radiation therapy may be used to treat those areas.
- Lobectomy: Some people with follicular or papillary thyroid cancer may have only part of the thyroid removed. The surgeon removes one lobe and the isthmus. Some people who have a lobectomy later have a second surgery to remove the rest of the thyroid. Less often, the remaining thyroid tissue is destroyed by radioactive iodine therapy.
Thyroid Hormone Treatment
After surgery to remove part or all of the thyroid, nearly everyone needs to take pills to replace the natural thyroid hormone. However, thyroid hormone pills are also used as part of the treatment for papillary or follicular thyroid cancer. Thyroid hormone slows the growth of thyroid cancer cells left in the body after surgery.
Thyroid hormone pills seldom cause side effects. Your doctor gives you blood tests to make sure you’re getting the right dose of thyroid hormone. Too much thyroid hormone may cause you to lose weight and feel hot and sweaty. It may also cause a fast heart rate, chest pain, cramps, and diarrhea. Too little thyroid hormone may cause you to gain weight, feel cold and tired, and have dry skin and hair. If you have side effects, your doctor can adjust your dose of thyroid hormone
Radioactive Iodine Therapy
Radioactive iodine (I-131) therapy is a treatment for papillary or follicular thyroid cancer. It kills thyroid cancer cells and normal thyroid cells that remain in the body after surgery.
People with medullary thyroid cancer or anaplastic thyroid cancer usually do not receive I-131 therapy. These types of thyroid cancer rarely respond to I-131 therapy.
Even people who are allergic to iodine can take I-131 therapy safely. The therapy is given as a liquid or capsule that you swallow. I-131 goes into the bloodstream and travels to thyroid cancer cells throughout the body. When thyroid cancer cells take in enough I-131, they die.
External Radiation Therapy
External radiation therapy (also called radiotherapy) is a treatment for any type of thyroid cancer that can’t be treated with surgery or I-131 therapy. It’s also used for cancer that returns after treatment or to treat bone pain from cancer that has spread.
External radiation therapy uses high-energy rays to kill cancer cells. A large machine directs radiation at the neck or other tissues where cancer has spread
Chemotherapy
Chemotherapy is a treatment for anaplastic thyroid cancer. It’s sometimes used to relieve symptoms of medullary thyroid cancer or other thyroid cancers.
Chemotherapy uses drugs to kill cancer cells. The drugs are usually given by injection into a vein. They enter the bloodstream and can affect cancer cells all over the body.
Every cancer diagnosis is different, just as every person who is diagnosed with cancer is different. Cancer knows no barriers to race, age, or social group. However there is one thing that each and every person who is diagnosed with cancer will have in common: help with fighting and beating the disease.
Life after being diagnosed with cancer will be different for everyone. Some people will have minimal disease and it will be a short chapter of their lives, while others will have a diagnosis that will change the course of the rest of their lives. Cancer diagnoses can change relationships, your routines, your work and home life. One thing is certain, no one person’s experience will be exactly the same. There are however, plenty of resources to learn about what life was like for other people, and what they did to achieve balance, maintain their health and personal life, keep peace of mind, and enjoy their lives with or after cancer.
Clinical Trials
The search for a cure for cancer is an ongoing, constant battle. Clinical trials are the basis upon which new treatments and medications are proven to help the fight against cancer, or if researchers should pursue another tactic. The advancement of medicine depends on willing and able cancer patients to volunteer for experimental treatments so that future generations will have proven and effective cures. Not every patient with cancer will be eligible for a clinical trial, as the scientific method needs specific patients with specific types of cancers. However, patients who are selected for trials may benefit from being at the cutting edge of new research, and gain time they otherwise might not have had.
The National Cancer Institute at the National Institutes of Health has a comprehensive database of over 10,000 ongoing clinical trials that both help advance medicine and help patients.
Financial Help
Unfortunately, cancer treatment can be costly, even if a patient has very comprehensive health insurance. For patients who do not have health insurance, the cost of treatment may seem insurmountable. Fortunately many pharmaceutical companies offer cost assistance to help make treatment more affordable. The National Comprehensive Cancer Network has compiled a Virtual Reimbursement Room where patients can find information for accessing financial help with their treatment costs.
If you have symptoms that suggest thyroid cancer, your doctor will help you find out whether they are from cancer or some other cause. Your doctor will ask you about your personal and family medical history. You may have one or more of the following tests:
- Physical exam: Your doctor feels your thyroid for lumps (nodules). Your doctor also checks your neck and nearby lymph nodes for growths or swelling.
- Blood tests: Your doctor may check for abnormal levels of thyroid-stimulating hormone (TSH) in the blood. Too much or too little TSH means the thyroid is not working well. If your doctor thinks you may have medullary thyroid cancer, you may be checked for a high level of calcitonin and have other blood tests.
- Ultrasound: An ultrasound device uses sound waves that people cannot hear. The device aims sound waves at the thyroid, and a computer creates a picture of the waves that bounce off the thyroid. The picture can show thyroid nodules that are too small to be felt. The doctor uses the picture to learn the size and shape of each nodule and whether the nodules are solid or filled with fluid. Nodules that are filled with fluid are usually not cancer. Nodules that are solid may be cancer.
- Thyroid scan: Your doctor may order a scan of your thyroid. You swallow a small amount of a radioactive substance, and it travels through the bloodstream. Thyroid cells that absorb the radioactive substance can be seen on a scan. Nodules that take up more of the substance than the thyroid tissue around them are called “hot” nodules. Hot nodules are usually not cancer. Nodules that take up less substance than the thyroid tissue around them are called “cold” nodules. Cold nodules may be cancer.
- Biopsy: A biopsy is the only sure way to diagnose thyroid cancer. A pathologist checks a sample of tissue for cancer cells with a microscope.
Your doctor may take tissue for a biopsy in one of two ways:
- Fine-needle aspiration: Most people have this type of biopsy. Your doctor removes a sample of tissue from a thyroid nodule with a thin needle. An ultrasound device can help your doctor see where to place the needle.
- Surgical biopsy: If a diagnosis cannot be made from fine-needle aspiration, a surgeon removes the whole nodule during an operation. If the doctor suspects follicular thyroid cancer, surgical biopsy may be needed for diagnosis.
Life after being diagnosed with cancer will be different for everyone. Some people will have minimal disease and it will be a short chapter of their lives, while others will have a diagnosis that will change the course of the rest of their lives. Cancer diagnoses can change relationships, your routines, your work and home life. One thing is certain, no one person’s experience will be exactly the same. There are however, plenty of resources to learn about what life was like for other people, and what they did to achieve balance, maintain their health and personal life, keep peace of mind, and enjoy their lives with or after cancer.
Your experience with cancer will depend on the type of cancer you have, your choices of treatment and the lifestyle you lead. Be sure to speak with your Doctor about the side effects of your disease and the treatments you choose. Your Doctor will be able to consult with you on realistic lifestyle expectations.
Early thyroid cancer often does not have symptoms. But as the cancer grows, symptoms may include:
- A lump in the front of the neck
- Hoarseness or voice changes
- Swollen lymph nodes in the neck
- Trouble swallowing or breathing
- Pain in the throat or neck that does not go away
Most often, these symptoms are not due to cancer. An infection, a benign goiter, or another health problem is usually the cause of these symptoms. Anyone with symptoms that do not go away in a couple of weeks should see a doctor to be diagnosed and treated as early as possible.
Doctors all over the country are conducting many types of clinical trials (research studies in which people volunteer to take part). Clinical trials are designed to answer important questions and to find out whether new approaches are safe and effective. Research already has led to advances in the diagnosis and treatment of thyroid cancer. Researchers continue to search for new and better ways to treat thyroid cancer.
People who join clinical trials may be among the first to benefit if a new approach is effective. And even if the people in a trial do not benefit directly, they may still make an important contribution by helping doctors learn more about thyroid cancer and how to control it. Although clinical trials may pose some risks, researchers do all they can to protect their patients.
Growths on the thyroid are often called nodules. Most thyroid nodules (more than 90 percent) are benign (not cancer). Benign nodules are not as harmful as malignant nodules.
Cancer cells can spread by breaking away from the original tumor. They enter blood vessels or lymph vessels, which branch into all the tissues of the body. The cancer cells attach to other organs and grow to form new tumors that may damage those organs. The spread of cancer is called metastasis.
There are several types of thyroid cancer:
- Papillary thyroid cancer: In the United States, this type makes up about 80 percent of all thyroid cancers. It begins in follicular cells and grows slowly. If diagnosed early, most people with papillary thyroid cancer can be cured.
- Follicular thyroid cancer: This type makes up about 15 percent of all thyroid cancers. It begins in follicular cells and grows slowly. If diagnosed early, most people with follicular thyroid cancer can be treated successfully.
- Medullary thyroid cancer: This type makes up about 3 percent of all thyroid cancers. It begins in the C cells of the thyroid. Cancer that starts in the C cells can make abnormally high levels of calcitonin. Medullary thyroid cancer tends to grow slowly. It can be easier to control if it’s found and treated before it spreads to other parts of the body.
- Anaplastic thyroid cancer: This type makes up about 2 percent of all thyroid cancers. It begins in the follicular cells of the thyroid. The cancer cells tend to grow and spread very quickly. Anaplastic thyroid cancer is very hard to control.