Postmenopausal hormone therapy and breast cancer: where do we stand?

The relationship between clinically apparent breast cancer and postmenopausal hormone therapy has been clarified in the last few years. It is clear that long-term, current users are at increased risk. Most women using HT for short-term treatment of vasomotor symptoms will not face measurable increases in their risk for breast cancer. That risk returns to baseline a few years after discontinuation of hormones. Breast cancer detection may be delayed by HT use; temporary interruption of HT prior to mammography may maintain sensitivity of that screening test. This article explores the literature as it has evolved from observational studies to prospective randomized clinical trials to see if a unified understanding of the epidemiology, biology and clinical significance of the potential risk temporally associated with prolonged HT use can be developed.