Moderate hypofractionation in locoregional radiotherapy was adopted by North American cancer centers during the COVID pandemic as a means to reduce breast cancer patients' daily attendance.In a phase III trial, the 3-year rates of arm lymphedema were similar with the standard radiotherapy dose of 50 Gy in 25 fractions over 5 weeks and the hypofractionated dose of 40 Gy in 15 fractions over 3 weeks.There were no differences in locoregional or distant recurrences, breast cancer mortality, or all-cause mortality between the two groups.
Hypofractionated locoregional radiotherapy for high-risk breast cancer was noninferior to standard fractionated radiotherapy for the 3-year incidence of arm lymphedema, with no significant differences in cancer outcomes, a Danish phase III trial showed.
Among over 2,900 patients, the 3-year rates of lymphedema were 9.4% with the standard radiotherapy dose of 50 Gy in 25 fractions over 5 weeks versus 8% with the hypofractionated dose of 40 Gy in 15 fractions over 3 weeks (OR 0.84, 95% CI 0.62-1.14, P=0.27), meeting the +5-percentage-point noninferiority margin, reported Birgitte V. Offersen, MD, PhD, of Aarhus University Hospital in Denmark, and colleagues.
