The use and recommendation of chemotherapy for women with both node-negative and node-positive early-stage breast cancer has declined in recent years, according to published survey results.
“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,” Allison Kurian, MD, associate professor of medicine at Stanford University, said in a press release accompanying the study. “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.”
Stephen Katz, MD, MPH, professor of medicine at University of Michigan, said in the press release that the study demonstrated how “breast cancer is a model for how doctors have driven advances in personalized medicine into the exam room to reduce overtreatment.”
The researchers performed a survey of 5,080 women diagnosed with breast cancer from 2013 to 2015 in Los Angeles and Georgia whether they received chemotherapy and whether their oncologists recommended chemotherapy. The researchers also surveyed 504 oncologists about making chemotherapy recommendations for node-negative and node-positive disease. Kurian and colleagues used a generalized linear mixed model of chemotherapy use over time, including clinical factors.
A total of 2,926 patients had stage I or stage II ER-positive, human epidermal growth factor receptor 2-negative breast cancer.
Chemotherapy use declined from 34.5% (95% CI, 30.8-38.3) in 2013 to 21.3% (95% CI, 19-23.7) in 2015.
For patients with node-negative disease/micrometastasis, chemotherapy use fell from an estimated 26.6% (95% CI, 23-30.7) to 14.1% (95% CI, 12-16.3).
Among patients with node-positive disease, use declined from 81.1% (95% CI, 76.6-85) to 64.2% (95% CI, 12-16.3).
The use of the 21-gene recurrence score remained the same over time patients with node-negative disease, and represented approximately one-third of the decrease in chemotherapy use.
After controlling for other factors, patients’ reports of having chemotherapy recommended by their oncologists fell from 44.9% (95% CI, 40.2-49.7) to 31.6% (95% CI, 25.9-37.9).
Oncologists appeared significantly more likely to order a recurrence score if patients preferences did not line up with their recommendations, with 67.4% (95% CI, 61.7-73) responding that they would order testing for a patient with node-positive disease. In situations where the patient’s wishes aligned with the oncologist’s recommendations, just 17.5% (95% CI, 13.1-22) responded that they would order testing. The oncologists adjusted their recommendations based on recurrence score results and patient preferences.
“We believe this study indicates that physicians are attempting to be more selective in their recommendations and to spare patients toxicity when possible,” Kurian said in the press release. “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.” – by Andy Polhamus
Disclosures: The authors report no relevant financial disclosures.