Those with a history of unilateral BC, in the following referred to as ‘survivors’ [4], face an average cumulative 20- to 25-year risk of contralateral BC of about 40 to 44% (BRCA1 mutation) or around 26 to 33.5% (BRCA2 mutation) [1, 5]. The gene discussed is BRCA1; the disease is breast cancer.