Estrogen-replacement therapy after breast cancer. Risks versus benefits.

In the current aging society, more than 30 million women have an average postmenopausal life expectancy of 28 years. Coronary heart disease is the leading cause of death in older women, and osteoporosis results in an estimated 1.5 million fractures per year. Various studies have suggested that postmenopausal estrogen-replacement therapy could reduce the morbidity and mortality associated with these conditions. Based on the results of several "natural experiments," it was proposed that estrogen-replacement therapy should be considered for menopausal women who have been treated successfully for breast cancer. The benefits and risks of estrogen-replacement therapy are reviewed, and recommendations for management and future research are suggested.