Clinical experience using hypofractionated radiation schedules in breast cancer.

Hypofractionation is attractive for whole- or partial-breast irradiation because it permits treatment to be given with fewer fractions in a shorter period of time and at less cost. A number of cohort studies suggest that hypofractionation may be given to the whole breast safely and with good local control. Recent randomized trials have confirmed that hypofractioned whole-breast irradiation is equivalent to more conventional whole-breast irradiation with respect to local recurrence and cosmetic outcome. Recently, there has been a renewed interest in hypofractionation for the delivery of partial-breast irradiation using a number of techniques including high-dose rate brachytherapy, 3-dimensional conformal radiation using external-beam techniques, and intraoperative therapy. Early cohort studies report good local control and acceptable morbidity. Randomized trials are now underway to compare this approach to conventional whole-breast irradiation.