Audit of Targeted Sentinel Node Biopsy (TSNB) in Patients With Limited Nodal Disease Undergoing Primary Surgery

Inclusion Criteria: * cT1-2N1M0 breast cancer\* * FNA or core biopsy confirmed axillary nodal metastases * ≤2 abnormal nodes on imaging * Undergo a dual tracer or single tracer sentinel node biopsy along with removal of the marked node (Targeted Sentinel Node Biopsy, TSNB) * 1 or 2 macrometastases identified in the removed nodes, with at least three nodes removed * If the sentinel node(s) cannot be localised on SNB: axillary node sampling should be performed, the patient will be eligible if 1 or 2 macrometastases are identified in the removed nodes, with at least three nodes removed. * If the node is not marked or the marked node is not removed, the patient will be eligible if 1 or 2 macrometastases are identified in the removed nodes, with at least three nodes removed‡. * patients with T3 tumours on post-operative histology will remain eligible. For multifocal/multicentric tumours, the cT stage is based on the size of the largest invasive tumour focus rather than the combined size of all tumours. * If \<3 lymph nodes are identified on histology, patient will remain in the NodeSMART registry. The decision regarding any further axillary treatment will be made by the treating MDT and recorded in the registry. Exclusion Criteria: * Neoadjuvant chemotherapy† * Previous ipsilateral axillary lymph node dissection * cT3-4 breast cancer * ≥3 abnormal nodes on imaging * Neoadjuvant endocrine therapy is permitted.