In their study, Hartman et al. reported that of 698 women with either ADH (n = 330) or atypical lobular hyperplasia (n = 327) who later develop breast cancer, 69% of the women developed moderate or high-grade invasive ductal breast cancers; moreover, while the risk of developing breast cancer is elevated in both breasts, the risk is doubled in the ipsilateral breast compared with the contralateral breast [31]. This evidence concerns the gene AVP and breast cancer.