Hormone replacement therapy and the risk of breast cancer

There is a growing use of hormone replacement therapy during menopause in the western world. Although most of epidemiologic studies have not found a cause-effect relation between this therapy and breast cancer, the fear of breast cancer related to this therapy limits its vast use. Controversy continues to surround the issue of the relationship between postmenopausal hormone therapy and the risk of breast cancer. Physicians, willing to prescribe this treatment, have often been asked by their patients if these hormones can cause breast cancer. Sufficient evidence exists to indicate the possibility of a slightly increased risk of breast cancer with long duration of hormone replacement therapy. However, the epidemiologic data on this cause and effect relation are inconsistent. Therefore, they cannot provide a definitive conclusion on this issue. Furthermore, evidence has shown that women treated with hormone replacement therapy have only localized disease with less metastasis than non-users. This might be due to detection/surveillance bias, but it might also be due to acceleration/deceleration of preexisting disease that reflects our misunderstanding of the breast cancer pathogenesis. Hormone replacement therapy has a cardinal role in the treatment and prevention of immediate and late sequela of menopause such as osteoporosis, cardiovascular diseases, urinary incontenence, etc. A large group of doctors such as family doctors, orthopedics, cardiologist, gynecologists and others recommend this therapy. Patients must also consider all the risks and advantages in their informed decision-making. Therefore we believe that it is important to review this treatment in connection with breast carcinoma.