Revisiting Margin Width Guidelines for Ductal Carcinoma In Situ and the Role of Routine Reexcision

1. Reexcision for wider margins may not be necessary for postmenopausal women with hormone receptor–positive ductal carcinoma in situ (DCIS) treated with breast-conserving surgery, according to NSABP B-35 trial. 2. Small differences in 10-year ipsilateral breast tumor recurrence rates were found based on margin width. 3. The study prompts reevaluation of margin width guidelines for this specific patient subgroup. 4. Ductal carcinoma in situ (DCIS) is the earliest type of breast cancer, confined to the milk ducts. 5. The NSABP B-35 trial included postmenopausal women with hormone receptor–positive DCIS between 2003 and 2006, and provided data supporting the potential for less frequent reoperations and improved patient experience without compromising long-term local control outcomes.