One week of hypofractionated radiotherapy after surgery for breast cancer is not inferior to a standard three-week schedule, according to results from a UK clinical trial.

In the FAST-Forward trial, 4096 women post-breast conserving surgery or mastectomy were randomised to standard care radiotherapy of 40Gy in 15 sessions over three weeks or to one of two hypofractionated one-week regimens of five doses totalling 27Gy and 26Gy respectively.

Almost two-thirds of the women had lower-risk breast cancer (grade 1 or 2) and the majority were aged over 50 years, while all had undergone axillary surgery with at most one node found to be positive, the authors reported in the Lancet.

In the trial, which was not blinded, results for the primary outcome of ipsilateral breast tumour relapse were not significantly different between the three groups, with 2.3%, 2.0% and 1.5% of women experiencing such relapse in the 40Gy, 27Gy and 26Gy groups respectively at a median follow-up of 71.5 months.