ATP 2016

Hypofractionation – breast Radiotherapy

• Adjusted α/β 4.6 Breast cancer is more sensitive to fraction size: No advantage in using ≤ 2 Gy fractions

• 4 phase III studies whole breast irradiation: Standard fractionation (25 x 2 Gy) vs. Hypofractionation Canada: 16x 2.66 Gy UK: 15x 2.67 Gy / 13x 3 / 13x 3.2 / 13x 3.3 Gy

• n = 7,000 patients; median follow-up 10 years

Haviland Lancet Oncol 2013, Yarnold RO 2005, Whelan NEJM 2010, START B Lancet 2008, START A Lancet Oncol 2008, Owen Lancet Oncol 2006