7 Healthcast: Breast cancer treatment

"We would like to be able to direct it to the person whose tumor requires it and we'd like to be able to spare somebody a therapy that's not going to be helpful to her or does her more harm than good," said Dr. Nancy Davidson.

One of the studies presented at the San Antonio meeting involved a widely used class of drugs called anthracyclines that can damage the heart.

Dr. Dennis Slamon of UCLA found that the drugs only attack tumors having a certain genetic makeup, a small percentage of breast cancers.

"Only 8% of the women based on our data really have a dramatic benefit of anthracycline-based therapy - yet 92 percent who don't have any incremental benefit get the drug today," Dr. Slamon said. "That needs to stop."

Another study involved a test called Oncotype that looks at 21 genes in the tumor to determine whether chemotherapy is needed. Doctors have already been using it for women whose was contained to the breast. The latest study looked at those where it was starting to spread.

"In our data set it was approximately 40 percent who could potentially avoid chemotherapy," said Dr. Kathy Albain.

The doctors emphasize that these studies are research in progress and will not be widely available for a few years. But the results from the meeting show that there is significant progress toward reducing chemotherapy, which can have enormous life saving benefits, but often with debilitating side effects.

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