MONDAY, Nov. 10, 2025 (HealthDay News) -- For patients with intermediate-risk, early breast cancer treated with mastectomy and adjuvant systemic therapy, chest-wall irradiation does not improve survival, according to a study published in the Nov. 6 issue of the New England Journal of Medicine.Ian H. Kunkler, M.B., B.Chir., from the University of Edinburgh in the United Kingdom, and colleagues conducted a phase 3, randomized trial to examine the omission of chest-wall irradiation in women with intermediate-risk breast cancer that was treated with mastectomy, an axillary procedure, and systemic therapy. Patients were randomly assigned to either undergo chest-wall irradiation (40 to 50 Gy) or not (808 and 799 patients, respectively, in the intention-to-treat population). Patients were followed for a median of 9.6 years.The researchers found that overall survival was 81.4 and 81.9 percent for chest-wall irradiation and no irradiation, respectively, according to 10-year Kaplan-Meier estimates (hazard ratio for death, 1.04; 95 percent confidence interval, 0.82 to 1.30; P = 0.80). Overall, 29 patients had a chest-wall recurrence: nine and 20 in the irradiation and no-irradiation groups, respectively (1.1 versus 2.5 percent; hazard ratio, 0.45; 95 percent confidence interval, 0.20 to 0.99). No significant between-group difference was seen in disease-free survival (76.2 and 75.5 percent for irradiation and no irradiation, respectively) or distant metastasis-free survival (78.2 and 79.2 percent, respectively)."We hope that our results stimulate a reevaluation of the evidence base for indications for chest-wall irradiation," the authors write. "Continuing to recommend chest-wall irradiation, in contexts in which evidence of benefit is marginal and the procedure is potentially detrimental, may divert limited resources from more effective treatments."Abstract/Full Text (subscription or payment may be required)Editorial (subscription or payment may be required).Sign up for our weekly HealthDay newsletter