Both normal cells and cancer cells are degraded by the radiation but the normal cells recover faster while the degradation of the cancer cells is cumulative.
As the radiation strikes the cancer cells it disorients the genetic material in the DNA. This prohibits the production of protein which is necessary for the cell to survive. In addition, certain biological changes also take place in the cell which ultimately result in the death of the cell. An analogy might be a computer driven attack by an enemy. Consider that you had the technology to bombard all the enemy command and control computers with a special form of radiation which completely scrambles the computer program code. Unable to properly function, the computer enters into a self destruct mode which also causes the destruction of the enemy forces.
The cancer cells do not die an instantaneous death when struck by the radiation. Rather, their internal genetic code is scrambled and they die over a period of months after the treatment stops. This programmed death is monitored by measuring the PSA which falls to below 1.0 as the cells die.
The additional attack provided by the androgen ablation has been proven to significantly improve results. A much more rapid decrease in the PSA provides this evidence along with microscopic examination when cells are removed during a test biopsy. The cancer cells die at a much faster rate and cure rates as high as 95% + are possible, based on biopsy studies, using the combined attack on the cancer cells. The cure rate is very dependent on the stage at which the disease is treated. The highest percent of cure rates apply to those cases which are caught early. Treatment of advanced cases may produce significantly lower rates of cure.