Risk of breast cancer associated with hormone replacement therapy

Purpose. The primary objective of this paper is to provide a brief overview of the risk of breast cancer associated with hormone replacement therapy (HRT) in healthy postmenopausal women, in breast cancer survivors, and in women at increased risk for breast cancer. Data Sources. The literature was reviewed through a MEDLINE search covering the years 1988 to 1999. Relevant articles cited in the literature obtained by MEDLINE searching were also considered. The following terms were searched: estrogen, progesterone, breast cancer, and HRT. The search was restricted to the English language. Data Extraction. The current literature is reviewed with regard to the risk of breast cancer associated with HRT in healthy postmenopausal women, in breast cancer survivors, and in women at increased risk for breast cancer. Data Synthesis. HRT is used commonly in postmenopausal women to alleviate both climacteric menopausal symptoms such as hot flashes and urogenital atrophy and to reduce the degree and frequency of osteoporosis. However, exposure to estrogen is one of the most important risk factors for breast cancer, and HRT is a relative contraindication in women with a personal history of breast cancer. The majority of epidemiological literature indicates that healthy women taking short-term HRT are not at increased risk of developing breast cancer. In breast cancer survivors, HRT does not appear to increase the risk of relapse. Some epidemiological studies show that women with a family history of breast cancer are at a substantially increased risk of developing breast cancer when receiving HRT. The decision to use HRT should be made individually by each woman and her health care provider by weighing the expected benefits and potential risks of therapy.