ASCO 2018: Can Lymph Node Irradiation Improve Outcomes in Breast Cancer?
Posted: Monday, June 11, 2018
Outcomes in patients with early-stage breast cancer can be improved with radiation therapy applied to chest lymph nodes, reported Philip Poortmans, MD, PhD, of the Institut Curie, Paris, France, and colleagues, at the 2018 American Society for Clinical Oncology (ASCO) Annual Meeting (Abstract 504). These 15-year results from the EORTC trial 22922/10925 demonstrated a reduction in breast cancer mortality and recurrence but no improvement in overall survival.
“Our results make it clear that irradiating these lymph nodes gives a better patient outcome than giving radiation therapy to the breast/thoracic wall alone,” declared Dr. Poortmans in a press release from the European Organisation for the Research and Treatment of Cancer (EORTC).
A total of 4,004 patients with stages I-III breast cancer were enrolled in the multicenter trial and followed for a median of 15 years. Nearly all patients with lymph node–positive disease and about two-thirds of those without received adjuvant systemic treatment.
Breast cancer mortality was 15.8% in patients who had irradiation of the internal mammary and medial supraclavicular lymph nodes versus 19.7% in patients who did not (P = .005). The probability of breast cancer recurrence was 24.5% in the treatment arm versus 27.1% in the control arm (P = .024). Overall survival in the group with nodal irradiation was 73.2%, compared with 70.8% in the control group. The authors plan to continue following this study population until at least 20 years from enrollment.
“Because there is a rather positive interaction between [systemic and locoregional] treatments, in many patients their combination will result in an enhancement of the combined benefits; in other words, one plus one can equal more than two,” added Dr. Poortmans in the EORTC press release.