[Comment] Who does not benefit from whole-breast radiotherapy and how to find them?

In The Lancet Oncology, Linda J Williams and colleagues present data from the 30-year update of the Scottish Breast Conservation Trial (SCT) comparing radiotherapy versus no radiotherapy after breast-conserving surgery in women with operable early breast cancer.1 Briefly, local control (measured as ipsilateral breast tumour recurrence) was significantly better with radiotherapy versus without radiotherapy; however, this effect was only apparent within the first 10 years of follow-up, and there was no further benefit in the 20 subsequent years (hazard ratio [HR] 0·98 [95% CI 0·54–1·79]).