External beam radiotherapy is an effective treatment option for localised prostate cancer. It typically involves daily treatment for approximately 8 weeks however shorter protocols can also be used. In some cases extra radiation can be delivered to the prostate by inserting small tubes into the prostate through the skin behind the scrotum. These are used for a short time to deliver iridium which is a radioactive substance to the prostate to provide extra radiation in an attempt to control more aggressive cancers. This is called high dose rate (HDR) brachytherapy. HDR cannot be performed if your prostate is too large and / or you have severe urinary symptoms already.
The advantage of radiotherapy is that it avoids major surgery. However the major disadvantage is that there are limited options available if the cancer is not totally cleared. This is because radiation damages the tissues and inhibits healing processes. Surgery, ultrasound treatment (HIFU) and freezing of the prostate (cryotherapy) are options in cases of radiation failure but the complication rates of these salvage treatments can be significant. It is for these reasons that radiotherapy is generally not recommended in the very young man.