How to judge the association of postmenopausal hormone therapy and the risk of breast cancer

Abstract

The relevance of postmenopausal hormone therapy (HT) for breast cancer risk has been long debated, although it is one of the most important barriers for women to accept HT. Various opinions have been reported from recent randomized clinical trials and epidemiological studies. These unanswered questions include: whether HT has a positive impact on breast cancer; whether risks of therapy with unopposed estrogen and combined estrogen-progestin are different; and whether different types and routes of estrogen and progestogens, as well as the duration and cessation of HT use, have different impacts on this disorder. Recently, there has been some good news such as the following: the currently available data do not provide sufficient evidence to prove a causal relationship between postmenopausal HT and breast cancer; breast cancer in postmenopausal women using HT usually has better prognosis than that of nonusers. In conclusion, HT is still the most effective method of relieving climacteric symptoms for many postmenopausal women. However, a possible risk of breast cancer associated with long-term HT usage should not be ignored. With respect to prevention of breast cancer, regular evaluation of individual breast cancer susceptibility and close follow-up through mammography and/or breast sonography are necessary strategies for the safety of HT use.

Key words： breast cancer; postmenopausal hormone therapy; unopposed estrogen therapy; combined estrogen-progestin therapy

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