About Thyroid Cancer and Thyroid Nodules
General Information
The thyroid is a small, butterfly-shaped gland located at the base of the neck, below the Adam’s apple. The thyroid only weighs about an ounce but can have a tremendous impact on your health. The thyroid’s function is to create thyroid hormone. This hormone regulates every aspect of your metabolism.
Thyroid nodules occur when cells in the thyroid multiply abnormally and form a growth. Thyroid nodules can be malignant (cancerous) or benign (not cancerous). Most thyroid nodules are benign.
Less than 10% of thyroid nodules are cancerous. While thyroid cancer is uncommon in the United States, rates seem to be increasing. It may be that advances in technology allow doctors to find thyroid cancers that would have been missed in the past. It is possible for thyroid cancer to spread (metastasize) to other tissue and organs. Thyroid cancer is usually found early and treatments work well.
Facts About Thyroid Cancer and Thyroid Nodules
Following is information on thyroid cancer and thyroid nodules.
Thyroid Nodules
Normal thyroid cells may grow, forming a solid or fluid-filled lump in the thyroid. There are generally no symptoms. However, nodules may grow large enough to press on the trachea or esophagus, or may cause hyperthyroidism. Only 5% of nodules are cancerous.
Thyroid Cancer
Cancerous thyroid nodules are often detected by a lump in the thyroid or swelling in the neck. The majority of people with thyroid cancer have excellent long term prognoses due to the availability of safe and effective therapies.
Here are some additional facts about thyroid cancer:
- Thyroid cancer is the most common cancer of the endocrine system (glands).
- Thyroid cancer is three times more common in women than men.
- Thyroid cancer can occur at any age, but most commonly after the age of 30.
- The American Cancer Society estimates that over 56,000 new cases of thyroid cancer will be diagnosed in the United States in 2012 (about 43,000 in women and 13,000 in men).
- Thyroid cancer is one of the least deadly cancers with the 5 year survival rate for all cases at about 97%.
Risk Factors and Symptoms
Risk Factors for Thyroid Cancer and Thyroid Nodules
Following are risk factors for thyroid cancer and thyroid nodules.
Thyroid Nodules
Following are some risk factors for developing thyroid nodules:
- Being female
- Aging
- Family history of thyroid nodules
- Radiation exposure (i.e. radiation therapy)
- History of thyroiditis (chronic inflammation of the thyroid)
Thyroid Cancer
Scientists have found a few risk factors that make a person more likely to develop thyroid cancer. However, most people with thyroid cancer have no apparent risk factors.
Following are some risk factors for thyroid cancer:
- Being female
- Younger than 30 or older than 50
- Family history of thyroid cancer
- Radiation exposure (i.e. radiation therapy)
- Pregnancy when age 30 or older
- Certain genetic disorders
Reducing the Risk
There are no known ways to reduce the risk of developing thyroid cancer or thyroid nodules. However, a healthy diet that is high in fruits and vegetables and low in animal fat can reduce your risk of developing many types of cancer, including thyroid cancer.
Symptoms of Thyroid Cancer and Thyroid Nodules
It is possible that you may notice a lump in your throat yourself or go to the doctor because you are experiencing other symptoms of thyroid cancer or nodules. However, it’s more likely that your doctor will notice a lump during a routine physical exam, or on images taken of your neck for another purpose.
When thyroid nodules or cancer do produce symptoms, they include the following.
Thyroid Nodules
Most benign thyroid nodules do not produce symptoms. However, occasionally they become large enough to notice a lump or swelling in the neck. Some nodules may over-produce thyroid hormone, causing the symptoms of hyperthyroidism.
A few patients with thyroid nodules may experience pain in the jaw, neck or ear. A large nodule may cause the following:
- Difficulty swallowing
- Tickling sensation in the throat
- Shortness of breath
Hoarseness is also a possible, although rare, symptom of thyroid nodules.
Thyroid Cancer
Following are potential symptoms of thyroid cancer:
- Lump in the neck, sometimes growing rapidly
- Neck pain
- Hoarseness
- Difficulty swallowing
- Difficulty breathing
- Persistent cough that is not due to a cold
These symptoms may be caused by other illnesses also. If you have any of these symptoms, promptly contact your physician to determine the cause.
Diagnosis and Treatment
Diagnosing Thyroid Cancer
Ultrasound is used to determine the exact size of a thyroid nodule and whether it is solid or not. This exam can detect nodules that are too small to feel during a physical exam. An ultrasound may identify nodule characteristics that suggest cancer. However, a biopsy is generally performed to be certain. When thyroid nodules are not surgically removed, ultrasound may be used to monitor changes in their sizes so appropriate action can be taken if and when needed.
An image guided biopsy is the most definitive test for distinguishing between benign and malignant nodules. While watching the ultrasound monitor, a radiologist carefully inserts a fine needle into the nodule(s) to remove cells for further testing.
Treating this Condition
Radioactive iodine therapy is used to treat thyroid cancer. A radioactive form of iodine is administered and absorbed by thyroid tissue, where it causes the gland to shrink. This therapy can also be used to destroy thyroid cancer cells that have spread to other parts of the body.