Supplementary Material for: Axillary surgical management in breast cancer patients after neoadjuvant systemic therapy: a Delphi Study

Introduction: The use of sentinel lymph node biopsy in post-neoadjuvant systemic therapy (NST) patients is an evolving practice for breast cancer surgeons. Our study sought to determine if controversial areas in the treatment of post-NST breast cancer patients had consensus among our panel of breast cancer surgeons at a single institution. Our group updated our care path for the surgical management of breast cancer in November 2022. We aimed to see the influence of the care path update on reaching consensus for the management of the axilla post-NST.
Methods: We performed two rounds of a modified eDelphi in 2021 and 2024 with a panel of 13 and 8 breast cancer surgeons, respectively, to evaluate a shift in expert opinion regarding axillary management in that period. Concordant responses were defined as greater than 75%.
Results: The panel reached consensus on sentinel lymph node biopsy for initially clinically node-negative patients, management of extracapsular extension, similar treatment of post-neoadjuvant chemotherapy patients and post-neoadjuvant endocrine therapy patients, and the value of dual tracer, MRI, and SAVI Scout. There was lack of consensus among the panel on management of micrometastases, management of isolated tumor cells, management of initially node-positive patients that downgraded to node-negative, use of lymphovenous bypass, and use of axillary radiation in post-neoadjuvant chemotherapy patients. Consensus was reached in 45% of questions in 2021 and 47% in 2023.
Conclusion: Despite having an institutional care path, our expert panel reached consensus regarding contemporary issues in breast surgery less than 50% of the time. Our study advocates for further research in the management of topics that did not reach consensus.