Therefore, it is conceivable that the osteo-neutral effect of TAM in elderly patients is undermined by various mechanisms of age-related bone loss, such as osteoporosis that has manifested prior to the primary diagnosis of BC, increased parathormone (PTH) levels due to impaired renal function, decline in physical activity, and secondary hyperparathyroidism. The gene discussed is PTH; the disease is secondary hyperparathyroidism.