HYpofractionated irradiation for PROstate cancer
A randomized multicenter phase III study.

In the last decade substantial improvements in the external-beam radiotherapy for prostate cancer have been made. Most attention has been focused on the introduction of new techniques and dose escalation has significantly increased treatment outcome. Less attention has been paid to fractionation. The disparity between ¦Á/¦Â = 4 Gy for late complications and the values for prostate tumors (¦Á/¦Â ¡Ü 2) raises the prospect that we might be able to further improve treatment outcome by treating prostate cancer with hypofractionation. Hypofractionated schedules for prostate cancer could lead to a high therapeutic gain as well as economic and logistic advantages. The study wants to demonstrate the superiority of the hypofractionated schedule with respect to the relapse rate. It will be a prospective, open, randomized phase III trial. Patients will be randomized to a total dose of 78 Gy in 39 daily fractions of 2 Gy, 5 times/week, in 8 weeks or to a total dose of 64.6 Gy in 19 fractions of 3.4 Gy, 3 times/week, in 7 weeks.
End-points will be the 5-year relapse-free survival after treatment and the acute and late gastro-intestinal and genito-urinary toxicity. Secondary end-points: quality of life.

The hypofractionated regimen of 19 fractions will result in an increase of relapse free survival by 10 % with the same acute and late toxicity as the standard fractionation of 39 fractions.

hypofractionation arm: total dose of 64.6 Gy in 19 fractions of 3.4 Gy, 3 times/week, in 7 weeks, using conformal EBRT
reference arm: 78 Gy total dose consisting of 39 fractions of 2 Gy, 5 times/week, in 8 weeks, using conformal EBRT