Your thyroid is a gland in your neck. It makes hormones that are important for controlling your metabolism, growth, and development. The pituitary gland in your brain controls the thyroid's production of these hormones. Thyroid problems can include hypothyroidism (underactive thyroid), hyperthyroidism (overactive thyroid), and thyroid nodules/tumors.
If you have had radiation that included your brain, thyroid gland, or came close to your thyroid gland (head & neck, upper spine, and upper chest) you are at risk for thyroid problems. Survivors treated with radioiodine therapy (I-131) or MIBG (meta-iodobenzylguanidine) therapy are also at risk.
The risk of thyroid problems continues for your whole life. Hypo- and hyper-thyroidism most often happen between 2 and 5 years after treatment. Thyroid nodules often develop 10 years or more after treatment. The risk of thyroid issues increases with the amount of radiation received to the area. Higher doses of radiation mean the risk is higher.
Symptoms of hypothyroidism (the most common complication) are a result of the thyroid not making enough of the hormones. These include:
Symptoms of hyperthyroidism are a result of the thyroid making too much of the hormones. These include:
Thyroid nodules can appear as a painless bump or lump in your neck. Depending on the location, you may be able to feel it, or it can press on your throat causing symptoms like trouble swallowing or a change in your voice. Many thyroid nodules will have no noticeable symptoms.
If you are a childhood cancer survivor, you should know your risk and monitor your health. Some ways to monitor your health are:
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