Top Line: The indications for axillary dissection for breast cancer when radiation is planned are diminishingly small.
The Study: This US multicenter single-arm prospective trial enrolled 78 patients with cT1-2N1 hormone receptor-positive HER2-negative breast cancer with ≤3 clinically-involved nodes on preoperative axillary ultrasound. All patients were planned for upfront surgery (two-thirds breast-conservation, one-third mastectomy) followed by radiation. Enrollees underwent sentinel node biopsy with completion dissection reserved for ≥3 pathologically-involved sentinel nodes, extracapsular extension, matted nodes, or failure to retrieve the biopsy-proven node. The cohort reflects selection for patients who are not expected to have any of the high-risk pathologic features just described: 50% had only one clinically-involved node and median tumor size was 2.3 cm. Three or more sentinel nodes (median 5) were sampled in 96% of patients. Ultimately, roughly one-third had each 1, 2, or 3+ pathologically involved nodes, and 76% avoided completion dissection–5 patients declined recommended completion dissection. Interestingly, one-third of palpable metastatic nodes were neither blue nor radioactive, reinforcing never omitting good ole axillary palpation. Again, all patients received radiation: postmastectomy radiation with regional nodes (32%), whole-breast with regional nodes (51%), or even whole breast alone (17%). At a median follow-up of 25 months, there were no isolated axillary or locoregional recurrences. This supports findings from a similarly-conceived recently-reported Dutch trial.
TBL: A clear therapeutic role for completion axillary dissection of microscopic disease when radiation is planned remains to be clarified. | Mamtani, JAMA Surg 2026
The Study: This US multicenter single-arm prospective trial enrolled 78 patients with cT1-2N1 hormone receptor-positive HER2-negative breast cancer with ≤3 clinically-involved nodes on preoperative axillary ultrasound. All patients were planned for upfront surgery (two-thirds breast-conservation, one-third mastectomy) followed by radiation. Enrollees underwent sentinel node biopsy with completion dissection reserved for ≥3 pathologically-involved sentinel nodes, extracapsular extension, matted nodes, or failure to retrieve the biopsy-proven node. The cohort reflects selection for patients who are not expected to have any of the high-risk pathologic features just described: 50% had only one clinically-involved node and median tumor size was 2.3 cm. Three or more sentinel nodes (median 5) were sampled in 96% of patients. Ultimately, roughly one-third had each 1, 2, or 3+ pathologically involved nodes, and 76% avoided completion dissection–5 patients declined recommended completion dissection. Interestingly, one-third of palpable metastatic nodes were neither blue nor radioactive, reinforcing never omitting good ole axillary palpation. Again, all patients received radiation: postmastectomy radiation with regional nodes (32%), whole-breast with regional nodes (51%), or even whole breast alone (17%). At a median follow-up of 25 months, there were no isolated axillary or locoregional recurrences. This supports findings from a similarly-conceived recently-reported Dutch trial.
TBL: A clear therapeutic role for completion axillary dissection of microscopic disease when radiation is planned remains to be clarified. | Mamtani, JAMA Surg 2026