Brachytherapy is the process of using radioactive isotopes to treat cancer. In addition to offering external beam radiation, Sarah Cannon offers a host of brachytherapy options to aid in the fight against cancer. The Radiation Oncologist will determine if brachytherapy is an appropriate course of treatment or possibly it can be used in conjunction with external beam radiation. Common isotopes used in brachytherapy include Cs-137, Ir-192, I-125 and Pd-103. Cancers commonly treated using brachytherapy include prostate, breast, lung and various gynecological cancers.