Dec. 12 (UPI) -- Fewer women are receiving chemotherapy for the treatment of early stage breast cancer.
A new survey of some 3,000 women diagnosed with early stage breast cancer showed rates of chemotherapy declined between 2013 and 2015.
According to researchers at the Stanford University School of Medicine and the University of Michigan, the numbers suggest doctors are altering the way they practice and taking a more individualized approach to cancer treatment.
The latest data suggests physicians are increasingly opting for genomic testing of tumors when a patient's treatment preferences don't align with a doctor's treatment recommendation.
"For patients with early stage breast cancer, we've seen a significant decline in chemotherapy use over the last few years without a real change in evidence," Dr. Allison Kurian, an associate professor of medicine and of health research and policy at Stanford, said in a news release. "This likely reflects a change in the culture of how physicians are practicing, and a move toward using tumor biology to guide treatment choices rather than solely relying on clinical measures."
Chemotherapy offers benefits but also poses risks. For some patients, the risks may outweigh the benefits, and the latest numbers suggest doctors and patients are more regularly taking this reality into consideration.
"Our study shows how breast cancer is a model for how doctors have driven advances in personalized medicine into the exam room to reduce over-treatment," said Dr. Steven Katz, professor of medicine and of health management and policy at the University of Michigan.
Kurian and Katz surveyed 5,080 women, 2,926 of whom were diagnosed with stage-1 or -2 breast cancers. They asked the women about their treatment decisions, as well as the results of their tumor genomic testing.
The expression of a woman's estrogen receptor and growth factor receptor-2 can dictate treatment for breast cancer.
The researchers also surveyed 504 oncologists who had treated the women diagnosed with early stage breast cancer. Kurian and Katz inquired about how doctors and their patients decide whether or not to opt for chemotherapy.
The results of their study -- published in the Journal of the National Cancer Institute -- showed chemo treatments declined from 34.5 percent to 21.3 percent between 2013 and 2015. While many women declined chemo after their doctor's initial suggestion, the data showed oncologists are recommending chemotherapy less frequently. Chemo recommendations declined from 44.9 percent to 31.6 percent.
When doctors and patients do disagree, the research shows physicians are increasingly likely to order tumor genomic testing.
"We believe this study indicates that physicians are attempting to be more selective in their recommendations and to spare patients toxicity when possible," said Kurian. "As personalized medicine becomes more widely available, doctors are using test results as part of their dialogue with patients about their preferences and overall treatment goals. But the long-term outcomes of these recent changes in chemotherapy use are uncertain."