Whelan TJ, Julian JA, Berrang TS, et al. - In this randomized, non-inferiority trial in 33 cancer centers in Canada, Australia, and New Zealand of 2,135 female aged 40 years or older with ductal carcinoma in situ or node-negative breast cancer treated by breast-conserving surgery randomized to accept either external beam accelerated partial breast irradiation (APBI, n = 1,070) or whole breast irradiation (n =1,065), experts examined whether external beam APBI was non-inferior to whole breast irradiation. However, a few acute toxicities was noted, the regimen taken was correlated with a raise in moderate late toxicity and adverse cosmesis, which might be associated with the twice per day prescription. Moreover, cosmesis might not be influenced by other approaches like treatment once per day and thus, should be studied.