Each of the studies looked at various doses and regimens of chemotherapy, including regimens considered to be potentially more toxic than the others.
A number of factors influenced survival rates, including smaller tumor size, fewer positive lymph nodes, having more chemotherapy, and using the breast cancer drug tamoxifen. Age alone, however, didn't appear to influence survival rates, the study authors found.
Women over 65 were more likely to die of causes other than breast cancer. And they were slightly more likely to die as a result of the treatment than younger women were. Overall treatment-related mortality was 0.5 percent, and 1.5 percent for those women over 65.
"What this study basically showed is that we shouldn't prejudice our treatment decisions based on chronological age," said Dr. Jay Brooks, chairman of hematology and oncology at Ochsner Health System in Baton Rouge, La. "We have a lot of very healthy, older individuals, and to simply preclude someone from taking potentially lifesaving therapy because they've reached some chronological age is just wrong. Would you tell someone who's 68 with coronary vessel disease not to get a bypass?"
Both Novik and Brooks said that recent advances in tailoring breast cancer treatments to the individual patient have likely made the age disparity less of an issue.
"We're hopefully getting smarter in understanding cancer behaviors, which gives us better insight into which drugs to use," Novik said.
Brooks advised older women with breast cancer to "sit down and talk with their doctor about what their individualized risk of recurrence is. We have good tools to offer individualized treatment options, whatever your age."
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