Top Line: The Dutch are hoping that 10 years is the magic number for eeking out a victory for their hypofractionated prostate regimen in HYPRO.
The Study: Once again, this phase 3 trial randomized 820 men with intermediate- or high-risk prostate cancer to either dose-escalated hypofractionation (3.4 Gy x 19 = 64.6 Gy) or conventional fractionation (2 Gy x 39 = 78 Gy). The hypofractionation here, with an EQD2 of ~90 Gy assuming an α/β of 1.5, represented a true dose escalation, even when compared to the more-oft used hypofractionated regimen of 3 Gy x 20 = 60 Gy with an EQD2 of ~77 Gy or 2.5 Gy x 28 = 70 Gy with an EQD2 of 80 Gy. After more than a decade of follow-up, 10-year relapse-free survival was 65% vs 60% and 10-year overall survival was 69% vs 61% favoring—but not statistically significantly on multivariate analysis—the hypofractionated group. At the same time, physician and patient-reported toxicity trended worse.
TBL: Whole gland prostate dose-escalation may slightly improve disease control at the expense of GI and GU toxicity, once again supporting the concept of judicious focal tumor boosts. | Wiersma, Int J Radiat Oncol Biol Phys 2025
The Study: Once again, this phase 3 trial randomized 820 men with intermediate- or high-risk prostate cancer to either dose-escalated hypofractionation (3.4 Gy x 19 = 64.6 Gy) or conventional fractionation (2 Gy x 39 = 78 Gy). The hypofractionation here, with an EQD2 of ~90 Gy assuming an α/β of 1.5, represented a true dose escalation, even when compared to the more-oft used hypofractionated regimen of 3 Gy x 20 = 60 Gy with an EQD2 of ~77 Gy or 2.5 Gy x 28 = 70 Gy with an EQD2 of 80 Gy. After more than a decade of follow-up, 10-year relapse-free survival was 65% vs 60% and 10-year overall survival was 69% vs 61% favoring—but not statistically significantly on multivariate analysis—the hypofractionated group. At the same time, physician and patient-reported toxicity trended worse.
TBL: Whole gland prostate dose-escalation may slightly improve disease control at the expense of GI and GU toxicity, once again supporting the concept of judicious focal tumor boosts. | Wiersma, Int J Radiat Oncol Biol Phys 2025