BRCA2 and breast cancer: Notably, the studies with higher rates of breast cancer families such as Ding [31] (60% either BRCA2 pathogenic mutation carrier or strong family history of breast cancer), Liukkonen[35] (33.1% with significant familial history) and Kiluk [34] (29% with significant familial history) had 22.8%, 19% and 19.4% of their patients reporting a second primary respectively.