1123 – Omission of the sentinel lymph node after neoadjuvant chemotherapy in breast cancer

Abstract

Introduction: The treatment of breast cancer (BC), omitting sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy, reduces the need for surgical staging. Thus, the objective of this systematic review was to analyze treatment
alternatives of BC, with a focus on safety.
Methods: A systematic review conducted according to PRISMA Guidelines and registered in PROSPERO (CRD420261352762).
The research was conducted using PubMed and LILACS. In the PubMed database, the following terms were used: “Breast
neoplasms” AND “Sentinel lymph node biopsy” AND “Neoadjuvant therapy” AND “Axilla”, filters for the last 10 years, and
free access to the full text were considered. The PICO criteria included: Participants, adult patients with invasive breast
cancer undergoing neoadjuvant chemotherapy and documented preoperative axillary status; intervention, SLNB after
neoadjuvant chemotherapy with lymph node mapping; comparison, lymph node dissection after neoadjuvant chemotherapy or comparison with other treatments; outcome, clinical and oncological safety, sentinel lymph node detection
rate and false-negative, recurrence, overall survival, and surgical morbidity. Of the 250 articles selected, 38 were included.
Results: SLNB avoids complete axillary dissection without compromising recurrence. It has been proven effective in
patients without lymph node metastases and in those with recurrence, especially when ≥3 negative sentinel nodes are
identified. Isolated tumor cells or residual disease are associated with an excellent prognosis, allowing for a more conservative treatment with SLNB and directed axillary dissection (TAD). This type of treatment has demonstrated significant
efficacy in identifying residual disease, avoiding unnecessary dissections. Selection based on tumor subtype and treatment assessment via magnetic resonance imaging helped to reduce the false-negative diagnostic, supporting the reduction of surgical staging and morbidity, even with occult presentation of the primary tumor.
Conclusion: SLNB after chemotherapy is effective in suspected axillary involvement. Negative results and tumor subtype reduce the risk of false negatives and allow complete dissection to be avoided without compromising monitoring
and staging.
Ethics: Public data – Literature review.
Registry: PROSPERO CRD420261352762.