Herceptin cuts risk of breast cancer relapse, study says

A drug that targets only diseased cells has proved astonishingly effective against an aggressive form of early breast cancer - a long-sought breakthrough that has doctors talking about curing thousands of women each year in the U.S. alone.Herceptin, is already used for advanced cancer. But in three studies involving thousands of women with early-stage disease, it cut the risk of a relapse in half.

Several experts used words like "revolutionary," "stunning" and "jaw-dropping" to describe the findings.

Herceptin, known generically as trastuzumab, does not help everyone. For one thing, it is only for the estimated 20 percent of breast cancer cases in which tumors churn out too much of a protein known as HER2. In the recent studies, the drug was used along with standard treatments, including surgery and chemotherapy.

Still, such a sweeping effect has probably not been seen in cancer drugs since the advent a decade ago of tamoxifen, another medicine that transformed the treatment of the disease by homing in on cancer cells but sparing healthy ones, the AP reports.

Herceptin, made by Genentech, appears to have "changed one of the most worrisome kinds of cancers into one that may have a relatively good prognosis," said Dr. Ed Romond of the University of Kentucky. A.M.