Jagsi R, Griffith K, Harris E, Wright J, Recht A, Taghian A, Lee L, Moran M, Thomas T, Johnstone C, Rahimi A, Freedman G, Muzaffar M, Haffty B, Horst K, Powell S, Sharp J, Sabel M, Schott A, El-Tamer M. Planned Interim Analysis Results from a Prospective Multicenter Single-Arm Cohort Study of Patients Receiving Endocrine Therapy but Not Radiotherapy after Breast-Conserving Surgery for Early-Stage Breast Cancer with Favorable Biologic Features. International Journal Of Radiation Oncology • Biology • Physics 2019, 105: s7-s8. DOI: 10.1016/j.ijrobp.2019.06.392.Peer-Reviewed Original Research