Some breast cancer patients may forgo chemo, research suggests
Some patients with HR-positive and HER2-negative breast cancer may safely choose to skip chemotherapy treatment and simply undergo endocrine therapy after surgery, according to the results of a recent study published in the New England Journal of Medicine.
Results from S1007, the RxPONDER study, showed that postmenopausal women with HR-positive, HER2-negative breast cancer that has spread to three or fewer lymph nodes and has a recurrence score of 21 genes of 25 or less had no significant difference in five-year invasive disease-free survival when they had post-surgical endocrine therapy compared to those who had endocrine therapy and chemotherapy after surgery.
“In medicine, we sometimes add (treatments), but it’s also important to think about giving treatments when we really need them. We saw that these patients were not benefiting from chemotherapy, ”said Dr. Kevin Kalinsky, principal investigator of RxPONDER and associate professor of medicine at the Winship Cancer Institute at Emory University, in an interview with CURE®. Kalinsky explained that by avoiding unnecessary chemotherapy, patients can avoid the short and long-term side effects associated with treatment.
Although postmenopausal women had no additional benefit from chemotherapy, this was not the case for premenopausal women – who made up about a third of the patients included in the trial.
In the group of women who had not yet gone through menopause, a relative benefit of invasive disease-free survival of 40% was observed in those who had received chemotherapy plus hormone therapy compared to premenopausal women who had only had ‘hormonal therapy. This was true even for patients with low recurrence scores.
“There are a number of questions that were derived from this study,” Kalinsky said. “Is this benefit exclusively due to the fact that some patients stop having regular periods?” Or is there a difference in cancer biology between pre- and postmenopausal patients? So we’re currently making a big effort to look at tumors in premenopausal patients to see if we can help identify if there are any biological differences. This may explain why we see this differential advantage based on menopausal status. “
All of this research is focused on personalized treatment plans that improve outcomes and move away from the unique model of cancer treatment. Patients can also play a role in this change by talking to their clinicians about their individual risks and undergoing genomic testing, such as the 21-gene test used in this particular study.
“When these results come back, talk to your provider – (it doesn’t matter) if you’re pre-menopausal or post-menopausal – about the benefits of chemotherapy or not (getting it),” Kalinsky said, noting that the results from the A study like these will hope that patients feel more confident to forgo chemotherapy if it is not beneficial to them.
“Each conversation is an individualized conversation with the patient in front of you in terms of the risks and benefits that they are or are not willing to accept in order to reduce the risk. This data helps inform this one-on-one conversation, ”Kalinsky said.
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