Laura M. Freedman, MD
The use of post-mastectomy radiation has historically been a controversial topic in patients with 1 to 3 positive lymph nodes, according to Laura M. Freedman, MD. Revisions to the National Comprehensive Cancer Network (NCCN) guidelines have, however, have now allowed physicians to pinpoint the women who are most likely to benefit from the treatment.
Additionally, American Society for Radiation Oncology guidelines for accelerated partial irradiation have been revised to include younger patients with ductal carcinoma in situ (DCIS). Although these recommendations now encompass a greater percentage of patients with breast cancer, technological advances in CT scan-guided treatment have helped physicians target radiation doses.
“Treatment planning techniques, like proton and intensity-modulated radiation, allow for much better dose conformity,” says Freedman.
In an interview during the 2018 OncLive®
State of the Science Summit™ on Breast Cancer, Freedman, assistant professor, director of radiation oncology, Sylvester Comprehensive Cancer Center, University of Miami Health System, discussed the impact of the updated NCCN guidelines on clinical applications of radiation therapy in patients with breast cancer.
OncLive®: Can you discuss the state of radiation oncology in breast cancer, which you focused on in your presentation?
: There are many updates in radiation oncology that came from the 2017 San Antonio Breast Cancer Symposium. First, I wanted all from the medical, surgical, and radiation oncology communities to be aware of the updated guidelines for post-mastectomy radiation given in women who have pathologic T1/T2 tumors and 1 to 3 positive nodes. The guidelines have allowed us to assess the risk-benefit ratio and guide our patients in the decision-making process.
The next topic [of my presentation] was the update to the accelerated partial breast irradiation guidelines. We now have the opportunity to extend partial breast irradiation to more patients in light of new information about intraoperative accelerated partial breast irradiation. The technological advances we have seen in radiation oncology have made it easier for us to provide better outcomes for patients. When the toxicity is lower, the benefit ratio is higher. In that circumstance, we’re able to better treat patients and provide them with the most optimal outcomes.
Finally, I spoke about the re-irradiation guidelines that are helping physicians extend patients’ lives and provide cures. These options extend to patients who recur as well.
Why has post-mastectomy radiation been controversial in the past?
It’s very well known that patients with no lymph nodes involved do not derive a benefit from post-mastectomy radiation, although there are exceptions, such as high-risk patients and those with positive margins and early-stage tumors. Typically, they do not show additional benefit post- mastectomy. For patients with 4 or more positive nodes, the addition of radiation provides a positive benefit in terms of local recurrence and overall survival. The data on patients with 1 to 3 positive lymph nodes have been more difficult to obtain.