Based on cohort studies of long-term mortality and risk estimation models for the induction of secondary cancers following radiotherapy at least 15–20 years follow-up will be required to fully assess whether there is an increased long-term treatment induced cancer risk (Dasu et al, 2005; Darby et al, 2005) and subtle late toxicity from irradiation in BRCA1 mutation carriers. This evidence concerns the gene BRCA1 and cancer.