Chemotherapy "cocktails" that combine two to three drugs work better to help older women with breast cancer live longer than a single chemo drug, concludes a new study.
Chemo "cocktails" have been shown in previous research to improve breast cancer survival, but there have been few studies focusing on older patients, even though the average age of a woman diagnosed with breast cancer is 63.
For this study, researchers wanted to know whether patients aged 65 and older would benefit from a single chemo drug, called capecitabine and sold under the name Xeloda.
Because the drug is available in pill form, it would be more convenient and less toxic than standard chemotherapy infusions delivered by IV.
But the study, published in Thursday's New England Journal of Medicine, showed it was not nearly as effective in preventing metastasis, or cancer spread, in older women with early-stage breast cancer.
This study was conducted with 600 women aged 65 and older through the Cancer and Leukemia Group B of the National Cancer Institute's Clinical Trials Cooperative Group Program.
The study compared capecitabine to a chemo "cocktail" of either cyclophosphamide, methotrexate, and fluouracil (CMF), or doxorubicin plus cyclophosphamide.
The combination therapy provided significantly better outcomes than the single drug treatment.
"Patients who were randomly assigned to capecitabine were twice as likely to have a relapse and almost twice as likely to die as patients who were randomly assigned to standard chemotherapy," Dr. Hyman Muss of the University of Vermont and colleagues wrote.
As well, three years after completing the therapy, the rate of relapse-free survival was 68 per cent in the single-drug group versus 85 per cent in the combo-chemotherapy group.
Similar studies involving women younger than 70 years of age have also shown that combination therapies provide better outcomes, noted the authors.
"This study is important because it is among the first several trials specifically targeted to older women with early-stage breast cancer and shows that chemotherapy can make a difference," said Dr. Hyman Muss, professor of medicine at the University of North Carolina at Chapel Hill.
Because older breast cancer patients generally prefer oral to intravenous chemotherapy, drug companies should focus on creating an effective pill form for multi-drug treatment for older women with breast cancer, the authors conclude.
