As part of a two-step chemotherapy drug regimen designed to prevent a recurrence of the malignancy, the drug is given to women whose cancer has spread beyond the breast.
However, a new study suggests Taxol was useful to women who had overactive HER-2 genes - the target of the newer breast cancer drug Herceptin.
Those tumors are called "HER2-positive" because their cells produce an excess of the protein human epidermal growth factor receptor-2 (HER2). This is the most common form of the disease.
These women were about 40 percent less likely to have a recurrence if they received Taxol. However a new research suggest the drug may only be effective in a small percentage of women.
The new study, which is published in the New England Journal of Medicine, suggests roughly half of all breast cancer patients who get chemotherapy might be spared from the side effects of this drug or similar ones without significantly raising the risk their cancer will return.
More than 20,000 women each year in the United States suffer from breast cancer.
Dr. Daniel Hayes of the University of Michigan however added, "We want to make sure these data are correct before withholding it (Taxol) from some patients ... the stakes are high. On the other hand, we don't want to keep a therapy that doesn't work."
Taxol causes neurological side effects including numbness and tingling in the hands and feet. Some women do not benefit as much from chemo as others, the study authors said.
In an editorial accompanying the study, Dr. Anne Moore from Weill Cornell Medical College, New York City, concluded that "the days of 'one size fits all' therapy for patients with breast cancer are coming to an end.''
