Another New Breast Cancer Drug

Raloxifene, also called Evista, was recently approved for the treatment of osteoporosis, but a new study to be released next month is expected to show it reduces the risk for breast cancer by about 75 percent. That compares to 45 percent for tamoxifen. And, evista appears to have an added benefit, CBS News Correspondent John Roberts reports

Anita Washam was diagnosed with breast cancer after a routine mammogram in 1991. She took tamoxifen for 5 years following breast cancer surgery, but for the past 3 weeks, has switched to raloxifene.

"With tamoxifen, there was always that danger, you know, from day one that you were running the risk of another cancer," said Washam.

The cancer she's talking about is uterine cancer. In the breast, both tamoxifen and raloxifene block the effects of estrogen on cells, helping to prevent cancer. But in the uterus, tamoxifen stimulates tissue, and can actually cause cancer. Raloxifene doesn't stimulate uterine tissue, and may actually help protect it.

Dr. Steven Goldstein says there's no question which drug he'd prescribe.

He said, "I think if there's anyone you're considering giving tamoxifen to for prevention of breast cancer, that the data indicates clearly, you would prefer to use raloxifene in those people."

Raloxifene is just the first of a number of new estrogen blocking drugs being developed. Oncologist Larry Norton says that in the future they could dramatically reduce the incidence of breast cancer.

Dr. Larry Norton of Memorial Sloan Kettering Cancer Center says, "The whole class of drugs that interfere with the action of estrogen are very important breakthroughs. Which one of the drugs is going to turn out to be the best one or which combination will turn out to be the best, this is a topic for future research."

While it may be scientifically too early to be prescribing any drug to prevent breast cancer, it's expected many doctors will, saying the fear factor is so great, they have to do something.

For the full Roberts report, click above.

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