BRCA2 and breast cancer: Although two of the studies reported no significant breast cancer risk reduction associated with prophylactic oophorectomy in BRCA2 carriers (Eisen et al, 2005; Chang-Claude et al, 2007), the meta-analysis suggested that prophylactic oophorectomy offered a 53% reduction in risk of first primary breast cancer (95% CI 0.26–0.84).