Among the inclusion criteria, the patients needed to be postmenopausal women according to standard clinical criteria or receiving concomitant therapy with a luteinizing hormone-releasing hormone (LHRH) agonist; they needed to also have undergone therapy with aromatase inhibitors (anastrozole, exemestane, or letrozole) as an adjuvant treatment for breast cancer, or for chemoprevention, for at least 3 weeks and no more than 2 years at the time of enrollment. This evidence concerns the gene GNRH1 and breast cancer.