How is radiation used to treat prostate cancer?

Causes DNA break: Radiation causes a double-stranded dna break in the target (prostate). High dose of radiation to the target causes prostate to turn in to a non functioning organ. Radiation can be given from the outside called external beam radiation using x-rays or protons or it can be given from the inside using high dose rate or low dose rate (seeds) brachytherapy.

Two Main Effects: Radiation treatments help to kill prostate cancer through two pathways: immediate dna damage and longer-term blood vessel blockage. Cancer cells reproduce more often, so dna inside them can be damaged more easily. Using hormone manipulation, this effect can be maximized. Over time, the arteries irradiated clog from thickening of their walls from the xrays. This starves the cancer, killing it.