FDA: Tamoxifen May Cause Rare Aggressive Form of Uterine Cancer

The breast cancer drug tamoxifen may cause a rare, aggressive form of uterine cancer, according to the U.S. Food and Drug Administration.

AstraZeneca, makers of the drug, are now required to add a "black box" warning to the drug's labeling regarding the risk of uterine sarcoma.

For women who have already had breast cancer and are taking tamoxifen to avoid a recurrence, the benefits of the drug are still considered to far outweigh the risks.

But for women who have never had breast cancer but have been prescribed tamoxifen because they are considered at a high risk, the FDA suggests discussing with your physician the risks associated with tamoxifen.

The warning is also aimed at women who have a very early form of breast cancer that is confined to the milk ducts called ductal carcinoma in situ.

Although doctors were notified of the new warning by the FDA in May 2002, the FDA only recently posted the information on its Web site.

Other sources: FDA, New York Times