This review presents the contribution conformal treatment has made to the e
xternal beam treatment of prostate cancer drawing on 10 years of experience
with three-dimensional conformal radiation treatment in 1500 patients with
prostate cancer at our institution. Major contributions from other institu
tions and the Radiation Therapy Oncology Group (RTOG) clinical trials group
are also noted, Patient immobilization, computed;tomography (CT) scan iden
tification of the target in three dimensions and beams-eye-view conformal t
reatment portals are critical to the process. Higher doses of radiation a:r
e associated with a marked increase in cure rates as the dose-response curv
e is extremely steep. The advantage given by the high dose depending on pro
gnostic group ranges from 14% to 35% in 5-year cures. Conformal techniques
protect normal tissues so that late complications are rare and in fact fewe
r than those observed with standard radiation technique at standard radiati
on doses. Educational efforts are underway in the USA to assist practising
radiation oncologists to deliver the required radiation doses of 75-80 Gy s
afely. Conformal therapy cures more prostate cancers causing fewer complica
tions than standard treatment technique and standard dose. It must therefor
e be disseminated into the practice of radiation oncology worldwide.