Key clinical point: Omitting adjuvant radiotherapy may be an option for some older women with low-risk, hormone receptor-positive breast cancer who are receiving appropriate endocrine treatment.

Major finding: The 10-year rate of ipsilateral recurrence was lower with radiotherapy than without (0.9% vs. 9.8%, P = .00008), but there was no significant between-arm difference in 10-year overall survival (81.0% and 80.4%, respectively; P = .68).

Study details: A phase 3, randomized trial of 1,326 women age 65 and older with hormone receptor–positive, low-risk early breast cancer undergoing breast-conserving surgery and receiving adjuvant endocrine therapy with or without whole breast irradiation (40-50 Gy in 15-25 fractions).

Disclosures: The study was funded by the Chief Scientist Office (Scottish Government) and the Breast Cancer Institute at the Western General Hospital in Edinburgh, Scotland. Dr. Kunkler did not have any disclosures.