Hormone replacement therapy in women with a history of breast cancer

Health care professionals in modern Western societies will meet an increasing number of women surviving breast cancer. How the menopause of these women should be treated is still an open question. Use of hormone replacement therapy (HRT) may, at least in theory, increase the risk for recurrence of cancer, but its categoric refusal is a double-edged sword because it also denies these women all the undisputable health benefits HRT provides. This refusal is not, however, supported by the observational data available so far on this question, because HRT has not increased the risk for breast cancer recurrence. In fact, it is well established that HRT abolishes hot flushes and improves significantly these patients' quality of life. At present, we have no effective nonhormonal alternatives for the control of vasomotor symptoms, and the efficacy of phytoestrogens in the treatment of menopausal symptoms is unproven. Selective estrogen receptor modulators (SERMs) which protect against osteoporosis and perhaps also against breast cancer, and which may have beneficial effects on the cardiovascular system, aggravate hot flushes and are therefore not useful, at least in the first postmenopausal years. In some countries, progestins are often prescribed for the control of such patients' vasomotor symptoms, but their safety has never been assessed in clinical trials, and in theory they can be harmful. Randomized clinical trials (RCT) on the use of HRT in breast cancer survivors are underway, but their completion will take years, and even these may be open to criticism. Tibolone may appear to be an appealing alternative for HRT, but it should also be studied with RCTs in this indication. At present, a patient with a history of breast cancer must be given balanced information as to the possible benefits and risks of HRT, and she herself must make the decision whether or not to start HRT.