Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. External radiation therapy uses a machine outside the body to send radiation toward the area of the body with cancer.

Radiation therapy may work better in patients who have stopped smoking before beginning treatment. External radiation therapy to the thyroid or the pituitary gland may change the way the thyroid gland works. A blood test to check the thyroid hormone level in the body may be done before and after therapy to make sure the thyroid gland is working properly.