SAN FRANCISCO -- Venturing into the emotional minefield of gene testing for breast cancer, Kaiser Permanente researchers calculate that some "high-risk" women who test positive could cut their death rate by 90 percent -- if they have their breasts removed.
The researchers emphasize that this possibility should only apply to women who undergo testing because they have a strong family history of breast cancer. Most women, however, do not.
The calculation was part of guidelines for genetic testing that Kaiser presented Saturday at the annual meeting of the American Society for Human Genetics. That finding, though, provoked some criticism from other scientists.
"Not all women want a mastectomy," said Dr. Neil Holtzman, director of genetics and public policy studies at the Johns Hopkins Medical Institutions in Baltimore. "These guidelines could push Kaiser physicians to recommend this option. I'm troubled that they're going ahead and letting their physicians do this."
Although some studies have suggested that mastectomies prevent most breast cancer, in a few cases cancer has grown in remnants of breast tissue not removed.
But Dr. JoAnn Bergoffen, a geneticist at Kaiser's Santa Teresa Hospital in San Jose, Calif., who presented the guidelines, said the estimate of a 90 percent lower death rate was based on six studies. Although the studies are inconclusive, she said, they make up the best information available so far. "Women are asking for this procedure," she said. "You can't hide from it."
Despite his criticisms, Holtzman called the guidelines "the most sophisticated analysis I've seen yet."
Although small numbers of women have begun asking for mastectomies to prevent breast cancer, doctors haven't had reliable information to help decide when it is appropriate. Kaiser is developing guidelines for gene testing in breast cancer to help its doctors make rational decisions.
About one in eight women -- or 12 percent -- develop breast cancer sometime in their lives.
The Kaiser guidelines are still under development and don't yet spell out specifically which women have such a strong family history of breast cancer that they should be eligible for a genetic test. A woman with three close relatives -- such as a mother and two sisters -- would probably qualify. But it's not clear if someone with two close relatives would be eligible.
Pub Date: 11/04/96