Overprolonged adjuvant tamoxifen therapy in breast cancer.

While adjuvant tamoxifen therapy given continuously for 2-3 years can lead to a modest improvement in survival rates in early breast cancer, there is no evidence that prolonging tamoxifen administration beyond that time is likely to improve survival rates any further in unselected cases. In the case of advanced disease, an alternating tamoxifen/progestagen regimen has been shown to increase the response rate and also its duration, beyond that to be expected from either agent alone. The next generation of adjuvant trials in breast cancer needs to explore the potential of an alternating tamoxifen/megestrol regimen.