ABSTRACT
Simultaneous irradiation (SI) is defined by the initial performance of a radioactive iodine125 (125I) seed implant, which has a 60 day half-life, followed by external beam irradiation (EBRT). Since the external beam component is given 3 weeks postimplantation, intraprostatic malignant epithelium as well as benign prostate epithelium is irradiated simultaneously by two separate sources, which produces dose intensification. In addition, potential extracapsular disease is also treated by the follow-up external beam irradiation. Thus, integration of both methods of radiation should effectively treat clinically localized prostate cancer.
