Thyroid Cancer: Frequently Asked Questions
Q: What is the thyroid?
A: The thyroid gland is located in the front part of the neck, in front
of the trachea (windpipe) and esophagus (food-pipe).
Normally, it cannot be seen and usually cannot be felt. It has 2 lobes,
the left and the right lobe. These lobes are connected by a bridge of
tissue, called the isthmus, to form a dumbbell or butterfly-shaped organ.
The thyroid gland takes up iodine from the food we eat. It also makes
several important hormones, called thyroid hormones. Thyroid hormones
help regulate the body's metabolism, or how the body creates and uses
energy. The thyroid gland contains 2 main types of cells. Cells called
thyroid follicle cells make and store the thyroid hormone. Cells called
C-cells make a hormone called calcitonin. This hormone helps control the
calcium levels in the body.
Q: What are the parathyroid glands?
A: There are 4 small parathyroid glands usually attached at the back of
the thyroid gland. They make a hormone called parathyroid hormone. Parathyroid
hormone, along with the hormone calcitonin, controls the levels of calcium
in the blood.
Q: Who usually gets thyroid cancer?
A: Women get thyroid cancer more often than men do. Thyroid cancer is often
found at a younger age than most other adult cancers. In fact, nearly
2 our of 3 thyroid cancers are found in people younger than age 55. Very
few thyroid cancers occur in children and teens.
Q: If I have thyroid nodules does that mean I have thyroid cancer?
A: Most thyroid nodules (or lumps) are not cancerous. They are sometimes
found as lumps on the neck. People can get thyroid nodules at any age,
but older adults get them more often. A person may have a multinodular
goiter, which means that the thyroid has several nodules. These nodules
are sometimes cysts with fluid in them. There can also be extra lumps
filled with thyroid hormone, which are called colloid nodules. These are
not cancer. Without a biopsy and other tests, however, it is very hard
to tell what a thyroid nodule is made of and whether it is cancer or not.
Q: What are the different types of thyroid cancer?
Papillary carcinoma. This is the most common kind of thyroid cancer. It
occurs in about 80% of people with thyroid cancer. It is sometimes called
papillary cancer or papillary adenocarcinoma.
Follicular carcinoma. This is the second most common type of thyroid cancer.
It occurs in 10% of people with thyroid cancer. It is sometimes called
follicular cancer, follicular carcinoma, or follicular adenocarcinoma.
This kind of cancer usually starts in the thyroid follicle cells.
Medullary thyroid. This cancer occurs in less than 5% of people with thyroid
cancer. It is a cancer of the parafollicular or C-cells (named after their
production of calcitonin). It can occur sporadically or, in some cases,
there is a genetic link, which is called familial medullary thyroid cancer.
A blood test can be done to see whether someone carries the gene. If the
test shows the gene, family members of the patient should also be tested.
This is so that cancer can be prevented or found at an earlier stage in
those with the genes.
Anaplastic carcinoma. This occurs in about 2% of people with thyroid cancer.
It is also called undifferentiated because the immature cells do not look
like the thyroid cells. This type of cancer grows quickly and can be harder
to treat than the other types of thyroid cancer.
Q: What are the symptoms of thyroid cancer?
A: Some of the symptoms of thyroid cancer include: a lump over the thyroid
or elsewhere in the neck, neck pain, neck swelling, hoarseness, trouble
swallowing, trouble breathing, and a cough that lasts for a long time
and is not related to a cold. These symptoms can be caused by many other
things besides thyroid cancer. It is important to be checked by a doctor
if you have any of these symptoms.
Q: How is the thyroid scan done?
A: In a thyroid scan, the person will either swallow or be injected with
a very small amount of radioactive iodine. A special camera will measure
how much iodine is taken up by the thyroid. The scan may show areas within
the thyroid without iodine uptake. These are called cold spots and can
represent cancer. A biopsy of these is needed because many cold areas
are not cancerous. Whole body scans are most helpful after a diagnosis
of cancer is made, and can help tell doctors if the cancer has spread
to places outside the thyroid gland. Blood tests, including the thyroglobulin
test, are also usually done.
Q: How is thyroid cancer treated?
A: Thyroid cancer may be treated with surgery, radioactive iodine therapy,
radiation therapy, chemotherapy, or a combination of these.
The goal of surgery is to remove the tumor from the thyroid, while leaving
as much of the thyroid as possible intact. Sometimes the entire thyroid
may have to be removed. If this happens, patients will need to take thyroid
hormone pills for the rest of their lives, to replace their own missing
The goal of radioactive iodine therapy (RAI) is to kill cancer cells using
radioactive iodine. RAI is a special form of radiation using iodine. The
thyroid cells are uniquely hungry for iodine and pick it up from the blood
after injection. This leads to high doses within both the normal and cancerous
thyroid, which will kill these cells. Other cells in the body, which do
not take up iodine do not get radiation and avoid destruction. If needed,
radioiodine treatments can be repeated more than once, to make sure all
cancer cells are destroyed. (The same radioactive iodine is used to do
a thyroid scan, but much larger doses are used for this treatment.)
The goal of radiation therapy is to kill cancer cells using X-rays. This
treatment is used to shrink a tumor before surgery or to get rid of any
remaining cancer cells after surgery. Sometimes it is used to treat cancers
that cannot be surgically removed.
Chemotherapy is rarely used to treat thyroid cancer. Chemotherapy may be
given along with radiation to treat anaplastic thyroid cancer. In thyroid
cancer, chemotherapy is less effective than radioactive iodine therapy
and usually used when the cancer has spread or has not responded to the
Q: What are clinical trials?
A: Clinical trials are studies of new kinds of cancer treatments. Doctors
conduct clinical trials to learn about how well new treatments work and
what their side effects are. If they look promising, they are then compared
with the current treatment to see if they work better or have fewer side
effects. People who participate in these studies may benefit from access
to new treatments before the FDA approves them. Participants also help
further our understanding of cancer and help future cancer patients. Clinical
trials studying the effectiveness of multikinase inhibitors have recently
shown promise for treatment of thyroid and other cancers which have been
resistant to other therapies
Q: Should everyone get a second opinion?
A: Many people with cancer get a second opinion from another doctor. There
are many reasons to get a second opinion, including if the person is not
comfortable with the treatment decision, if the type of cancer is rare,
if there are different ways to treat the cancer, or if the person is not
able to see a cancer expert.
Q: How can someone get a second opinion?
A: There are many ways to get a second opinion:
Ask a primary care doctor. He or she may be able to recommend a specialist,
such as a surgeon, medical oncologist, or radiation oncologist. Sometimes
these doctors work together at cancer centers or programs.
Seek other options. Patients can get names of doctors from their local
medical society, a nearby hospital, a medical school, or local cancer
advocacy groups, as well as from other people who have had the same type