Late morbidity and oncological outcome after radical hypofractionated radiotherapy in men with prostate cancer

Objective: To test the hypothesis that three-dimensional hypofractionated radiotherapy (3D-HFRT) is well tolerated and not worse than 3-D conventional RT (3D-CRT) for oncological outcome.

Patients and methods: In all, 162 men with hystologically confirmed prostate adenocarcinoma were included in the analysis. In all, 82 men were treated with 3D-HFRT (15 fractions of 3.62 Gy delivered 3 times/week; a total dose of 54.3 Gy). This group was retrospectively compared with 80 men who met the same inclusion criteria and who were treated with 3D-CRT (39 fractions of 2 Gy delivered daily; a total dose of 78 Gy). A short course of hormone therapy was administered concomitantly with the RT.

Results: Only one (1.7%) patient in the 3D-CRT group and two (4.0%) in the 3D-HFRT group had Grade 3 genitourinary toxicity. There was late gastrointestinal morbidity of ≥ grade 3 in only 5.1% of men treated with 3D-HFRT and in 4.0% of men treated with 3D-CRT. In both groups there was no Grade 4 toxicity. At the median (range) follow-up of 45 (39.4-51) months for the 3D-HFRT group and 57.5 (54.9-59.1) months for 3D-CRT group the progression rate was 18/82 (21.9%) and 20/80 (25.0%), respectively, with no significant worsening in the risk of biochemical failure (BCF; log-rank test, P= 0.222).

Conclusions: In the present study, men with clinically localized prostate cancer had similar levels of morbidity irrespective of whether they received HFRT or CRT without any worsening in the early risk of BCF. Thus, the present data provide some clinical evidence to justify trends already emerging toward HF regimens for treating clinically localised prostate cancer.