In radiation therapy uses high-energy x-rays (or particles) to kill cancer cells. Radiation therapy is not used often as the main initial treatment for adrenal cancer because the cancer cells are not easy to kill with x-rays. Radiation may be used after surgery to help keep the tumor from coming back. This is called adjuvant therapy. Types of radiation surgery: A. External beam radiation therapy (focuses radiation on the cancer from a machine outside the body). B. Brachytherapy: This is internal radiation therapy uses small pellets of radioactive material placed next to or directly into the cancer, sometimes in thin plastic tubes. The tubes containing the pellets are left in place for a few days and then removed. This type of radiation is not often used to treat adrenal cortical carncer.