it shows taxanes ARE helpful in those who are her2+ Here it is:
Oct. 10, 2007, 11:33PM
Study gives hope of narrowing breast cancer chemo
Finding could help refine therapy
By TODD ACKERMAN
Copyright 2007 Houston Chronicle
SURPRISING RESEARCH ON TAXOL
The widely used chemotherapy drug Taxol does not work for the most common form of breast cancer and helps far fewer patients than has been believed, surprising new research suggests. If further study bears this out, more than 20,000 women each year in the United States alone might be spared the side effects of this drug or similar ones without significantly raising the risk their cancer will return. That would be roughly half of all breast cancer patients who get chemo now. In the study, Taxol did the most good for women who had overactive HER-2 genes — the target of the newer breast cancer drug Herceptin. These women were about 40 percent less likely to have a recurrence if they received Taxol. Conversely, Taxol did not significantly help women whose tumors were HER-2 negative and were being helped to grow by estrogen. This is the most common form of the disease.
Researchers have learned how to target chemotherapy for breast cancer to only those women most likely to benefit, an advance that should spare roughly 20,000 women annually from unnecessary side effects.
The study by the University of Texas M.D. Anderson Cancer Center and other institutions found that women with the most common form of breast cancer didn't gain any benefit from the widely prescribed drug Taxol.
But those with overactive HER-2 genes — about 15 percent to 20 percent of women with breast cancer — were helped.
"We hope this discovery one day marks an end to the one-size-fits-all approach of chemotherapy," said Dr. Daniel Hayes, clinical director of the University of Michigan Comprehensive Cancer Center's breast oncology program and the study's lead author.
"Historically, treatment has been based on whether a woman is at high risk of the breast cancer recurring, without any idea of whether she'd benefit from additional therapy. In the future, we hope to focus chemotherapy on just those patients it's most likely to help."
The researchers are not recommending any changes in practice yet. They said more studies need to be conducted to confirm the finding.
The study appears in today's issue of the New England Journal of Medicine.
Following surgery, doctors typically prescribe more chemotherapy drugs if the cancer is in the lymph nodes and likely to spread. Taxol, also known as paclitaxel, is one of a class of drugs called taxanes added after four cycles of chemotherapy drugs Adriamycin and Cytoxan.
Previous research showed the cocktail produced a small but statistically significant benefit, and the result changed clinical practice. Taxol's use rose dramatically starting early this century.
But Taxol causes significant side effects, particularly numbness and tingling in the hands and feet. Eighteen percent of the women in the original study had the problem months and even years after taking Taxol.
Who doesn't need it?
"The most important question in invasive breast cancer is who does and doesn't need chemotherapy?" said M.D. Anderson biostatistics chief Don Berry.
"We're good at adding therapies to a patient's regimen, but not as confident subtracting them. This study suggests we'll be able to limit therapies to those who'll truly benefit from them, and other patients can be spared their side effects without loss of benefit."
The new study involved retrieving frozen tissue samples from 1,500 of the original study participants and conducting genetic tests to better identify their types of cancer. The researchers found a huge difference in who responded to Taxol.
Those with HER-2 genes, the target of the newer breast cancer drug Herceptin, had a 41 percent lower rate of having their cancer return. Those whose tumors were HER-2 negative and were being helped to grow by estrogen, the most common category of the disease, did not get added benefits.
In an accompanying editorial in the journal, Dr. Ann Moore, of Weill Medical College of Cornell University, joined Hayes in predicting the days of "one size fits all" therapy for breast cancer patients is coming to an end.
"Oncologists have a responsibility to their patients to be aware of this report," she wrote.
M.D. Anderson officials said they will wait for confirmation of the study results to change their patient regimens. Berry, for instance, is reanalyzing an earlier Taxol study.
In recent years, doctors increasingly have been able to target newer drugs, such as tamoxifen, aromatase inhibitors and Herceptin, for certain kinds of breast cancer patients. But such targeting had eluded chemotherapy.
todd.ackerman@chron.com