In the bone density sub‐study of the Austrian Breast and Colorectal Cancer Study Group (ABCSG)‐12 trial, zoledronic acid 4 mg IV, 6‐monthly prevented bone loss induced by combination LHRH agonist and tamoxifen, as well as in pre‐menopausal breast cancer patients on LHRH agonist and anastrozole [119]. This evidence concerns the gene GNRH1 and colorectal cancer.