5 years post-5 fractions.

Top Line: Satisfied with the safety of ultra-hypofractionated prostate radiation?

The Study: Next up, of course, is ultra-hypofractionated proton therapy. Here is a look at 279 men receiving prostate-directed intensity modulated proton therapy of 725 cGy x 5 = 3625 cGy for low and intermediate risk prostate cancer at a single Czech center from 2013-2016: 12% had unfavorable-intermediate risk and the rest were evenly split between low and favorable-intermediate risk. In other words, pretty darn good. Survival without evidence of biochemical recurrence at 5 years was 97% for low risk, 92% for favorable-intermediate risk, and 84% unfavorable-intermediate risk. What’s more, grade 2+ GI toxicity was <8% and grade 2+ GU toxicity only 5%. Wow. Granted this is not a head-to-head comparison, and there is a distinct population that gets proton therapy in a non-randomized real world. Nonetheless, these outcomes fare quite well compared to more prolonged photon treatment.

TBL: Five-year efficacy and toxicity rates with five-fraction proton therapy for low-intermediate risk prostate cancer are excellent from a single Czech institution. | Kubeš, Int J Radiat Oncol Biol Phy 2021