Journal of Trends in Technical and Scientific Research Keywords: Hypofractionated radiotherapy; Toxicities, Acceleration; Protocols; Sensitivity; Tissues Short Communication Hypofractionated radiotherapy for localized prostate cancer has recently been strongly recommended in evidence-based guidelines jointly published by ASTRO, ASCO and AUA [1]. While it has obvious advantages in cost and convenience, there remains a concern about associated acute and late toxicities: Two randomized controlled trials-HYPRO [2] and RTOG 0415 [3]-did identify a somewhat increased risk of late toxicity, and several, CHHiP [4], PROFIT [5], HYPRO and Fox Chase [6], all found increased risk of acute GI toxicity with hypofractionation. These concerns are greater when ultra-hypofractionation is used [1]. In order to reduce the acute and late toxicities, our group at Grand River Hospital, Kitchener, Ontario, back in 2006, started a Phase II trial [7] i...