New Findings from NRG Oncology/NSABP B-35

07/01/2026

“Results From the NRG Oncology/NSABP B-35 Randomized Clinical Trial” – JAMA Surgery article

New findings from the NRG Oncology/NSABP B-35 clinical trial suggest that many postmenopausal women with hormone receptor-positive ductal carcinoma in situ (DCIS) may be able to safely avoid additional breast surgery when lumpectomy margins are close. Investigators found that although narrower surgical margins were associated with slightly higher rates of local recurrence, margin width was not an independent predictor of recurrence after accounting for other patient and tumor characteristics. The results indicate that routine re-excision based solely on margins smaller than 1 mm or 2 mm may not be necessary for appropriately selected patients receiving whole-breast radiation and endocrine therapy, potentially sparing women from additional operations without compromising outcomes.

Citation: Wapnir IL, Cecchini RS, Dignam JJ, et al. Lumpectomy Margins and Local Recurrence in DCIS: Results From the NRG Oncology/NSABP B-35 Randomized Clinical Trial. JAMA Surg. Published online July 01, 2026. doi:10.1001/jamasurg.2026.2340