Corey Speers, MD, PhD, assistant professor at the University of Michigan, discussed personalizing radiation treatment in patients with breast cancer and how genomic signatures may help identify which patients may need radiation at the San Antonio Breast Cancer Symposium, held December 10-14, in San Antonio, Texas.
So, this is a really exciting time in breast cancer for making decisions about how to personalize radiation treatment. For a long time, we’ve had molecularly stratified genomic signatures that have helped us identify patients for whom chemotherapy is appropriate and will benefit, and we’re really on the cusp of being able to do the same things for decisions regarding radiation treatment. Both for whom radiation is likely to be effective or ineffective and in which patients really, we don’t need to offer radiation.
Currently, every patient, or almost every patient, who that undergoes breast conserving surgery is offered radiation as part of their adjuvant treatment given the relative risk reduction after surgery, but with the addition of radiation. But we know that 70% of women or more are cured with surgery and or systemic therapy alone and don’t need that radiation treatment, and so really the question is how, “Can we use these genomic signatures to identify the patients for whom radiation isn’t necessary?” And so that’s kind of where we’re at as a field is, we’re getting very close to having tests that can be used clinically to identify those patients both with preinvasive disease, so ductal carcinoma in situ, and also for those women with invasive breast cancer who doesn’t need radiation. And then, in the women who we don’t think radiation is going to be effective, how to identify those women up front so that we can think about ways to more effectively target radiation. Could be either by increasing doses of radiation, bigger fields of radiation, adding a radiosensitizer during their treatment, that’s really where we’re at now. And there’s some tests that are coming to market in the next couple of years that I think will be useful in making those decisions.