The Management of Positive Axillary Nodes in Early Stage Breast Cancer: Analysis of Practice Pattern Concordance with Landmark Trials

Axillary nodal dissections (ALND) were historically performed in the management of early stage, node-positive breast cancer. Since the ACOSOG Z0011 landmark study demonstrated that patients with clinically negative axillae and 1-2 positive sentinel lymph nodes could be spared the morbidity of an axillary dissection, surgeons have widely adopted the omission of ALND. However, the practice patterns in the adjuvant setting remain less clear, and our current work wishes to address this gap by assessing the management of early stage breast cancer at our institution. We performed a retrospective analysis of 504 women with cT1/T2 N0 breast cancer undergoing breast conserving therapy (BCT) between 5/2011-6/2016 and collected data regarding the clinico-pathological characteristics of the tumors and the adjuvant therapies received. Overall, 97% patients completed a SLNB, while 3% underwent upfront ALND. None of SLNB positive patients had further axillary surgery. In the SLNB positive cohort however, adjuvant therapies consisted of 61.5% patients receiving regional nodal irradiation. Further analysis revealed that factors such as tumor type, T and N stage, hormone receptor status, tumor grade, the presence of LVSI, patient age, and patient race, did not correlate with clinician decisions to deviate from ACOSOG protocol recommendations regarding adjuvant therapy. Our work suggests that although ACOSOG Z0011 recommendations for minimizing axillary surgery in patients with limited nodal disease has largely been adopted at our institution, node directed radiation therapy continues to be relatively commonplace. Interestingly, the delivery of nodal irradiation was not associated with common clinic-pathological factors.