Recent studies show that a drug generally used for advanced breast cancer is astonishingly effective against an aggressive form of early breast cancer.
"I don't think I've ever seen this level of excitement about a new therapy or treatment for breast cancer," said Dr. Susan Troyan of Beth Israel Deaconess Hospital in Boston.
In 20 percent of women diagnosed with the disease, Herceptin, made by Genetech, Inc., may reduce the risk of relapse by 50 percent.
The usually reserved New England Journal of Medicine wrote, "The results are simply stunning. They're not evolutionary, they're revolutionary."
The government approved Herceptin in 1998 for advanced breast cancer that already has spread within the body, but early-stage cases are more common.
"This produces real results both in reoccurrence and in survival, and it works on a biological/molecular level so it is a natural method rather than the toxins and chemicals used for chemotherapy," said ABC medical contributor Dr. Tim Johnson. "The results confirm that there is a new way to treat breast cancer."
Three new studies that followed more than 6,500 women with early-stage breast cancer found that patients on Herceptin showed a disease-free survival rate that was 12 percentage points higher than without it.
Kristie Naimes was diagnosed with an aggressive form of breast cancer two years ago at the age of 30.
"I was given very little hope," Naimes said. "I was given less than a 30 percent chance of living five years and not being able to see my daughter grow up. I was told that Herceptin could be my one shot at life."
After surgery to remove the tumors, Naimes got traditional chemotherapy, the Herceptin, a much more targeted drug, also given intravenously.
"I'm in perfect health," said Naimes, now 32. "My cancer has not come back."
While Herceptin is a breakthrough, it is not a cure. Approximately 211,000 women are diagnosed with breast cancer each year, and 40,000 die. Herceptin will help one in five women with breast cancer, or about 20 percent. Some doctors estimate about 30,000 women could be taking Herceptin in the next couple of years, curing about 7,000 women who would otherwise relapse.
"These are women whose tumors, when tested in a lab, are positive for something we call HER2, which is a protein," Johnson said. "Women who test positive for this and have positive nodes will almost certainly be treated with this drug and I think even women who have negative nodes but larger tumors will be treated."
A year of Herceptin costs $48,000. Herceptin has the same kind of benefits as tamoxifen, discovered a decade ago, but tamoxifen works against another large class of cancer cases known as estrogen-positive.
Johnson said the most serious side effect of Herceptin is heart failure, which occurs in about 4 percent of the women treated. Women with pre-existing heart conditions should not take the drug under current guidelines.
"But even heart damage can be treated so it would not be life-threatening," Johnson said.
Researchers are currently testing whether Herceptin is most effective when given at the same time as chemotherapy or immediately after. Johnson said there is hope the drug could some day replace chemotherapy, and it is also possible Herceptin will be found to help those who have been cancer-free for years.
"It's unclear after what period of time following chemo the drug would be effective," Johnson said. "But there is the possibility that women who had chemo less than two years ago will be given the drug."