External-beam radiotherapy is the most utilized radiotherapy modality for treatment of localized prostate cancer and local control is related to delivered dose. Three-dimensional conformal radiotherapy [3D-CRT) is a technique used to achieve this "dose escalation", but is limited by the consequent risk of excessive rectal and bladder complications Recently, the development of the intensity modulated radiotherapy (IMRT) has been shown to be a reasonable option to deliver higher radiation doses to prostate cancer patients, with acceptable low rates of complications. This study presents a retrospective evaluation of the following the technical implementation of EBRT/3D/IMRT, for treatment of localized prostate cancer patients. Clinical and treatment related factors, including normal tissue dose-volume histogram (DVH) constraints, were analyzed as possible risk factors