Safety and Efficacy of 21 Gy, 23 Gy and 25 Gy for High Dose Rate (HDR) Prostate Brachytherapy

"* Dose constraints for 21 Gy:~ * Bladder and rectum: V70 \< 1 cc~ * Urethra: V115 \< 1 cc~ * V135: 0%~* Dose constraints for 23 Gy:~ * Bladder and rectum: V65 \< 1 cc~ * Urethra: V105 \< 1 cc~ * V125: 0%~* Dose constraints for 25 Gy:~ * Prostate V100 \>90% (\>95% preferred)~ * Bladder and rectum: V70 \< 1 cc, Dmax \<115%~ * Urethra: V110 \< 1 cc, Dmax \<120%"