Skip to main content
SSO 2024 Annual Meeting Main banner
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.
Presentation Icons
Recorded for On-Demand Viewing
Recorded for On-Demand Viewing
Back

Breast

E6: Comparison of Targeted Axillary Dissection versus Sentinel Node Biopsy Alone on Nodal Recurrence for Patients with Node-Positive Breast Cancer treated with Neoadjuvant Chemotherapy

Introduction: For patients with node-positive breast cancer whose axilla is clinically downstaged following neoadjuvant chemotherapy (NAC), prospective trials demonstrate an acceptable false-negative rate with sentinel lymph node biopsy (SLNB). While targeted axillary dissection (TAD) which includes SLNB and selective localization with removal of biopsy-proven metastasis has been adopted at several institutions, there is limited data evaluating nodal recurrence. This study compares axillary nodal recurrence between patients who had TAD versus those who underwent SLNB alone.

Methods: Consecutive patients with stage 2-3, biopsy-proven node positive breast cancer treated with NAC from August 2018 to June 2022 were identified. Patients who became clinically node negative after NAC (ycN0), had tumor-free SLNB, and avoided axillary lymph node dissection (ALND) were evaluated. Patients were divided into two groups—those who had a TAD and those who had SLNB alone.

Results: Of the 377 patients treated which NAC, 143 had stage II-III node-positive breast cancer. 105 patients converted to ycN0. 61 patients had an ALND due to positive nodes or failure to map. 44 patients avoided an ALND. Of these 44, 25 had a TAD and 19 had SLNB alone (Figure). Groups were clinically similar: median (IQR) age was 49 (39-54) years; median tumor size was 2.7cm (1.9-3.4cm); 25 (56.8%) tumors were HER2-positive, 8 (18.2%) were HR+/HER2-negative, and 11 (25%) were triple-negative. The median number of sentinel lymph nodes (SLN) retrieved was 4 (IQR 3-8) (overall 4, TAD 4, SLNB alone 4, p=0.55). SLNB alone was less likely to retrieve the biopsy-proven clipped node (clipped node retained: overall n=5/37, TAD n=1, SLNB alone n=4, p=0.03). 21 (48%) received doxorubicin-based NAC; 40 (90%) received adjuvant radiotherapy (RT), and 32 (73%) received regional nodal RT. At a median follow-up of 28 months, there were no axillary nodal recurrences in either group.

Conclusions: In patients with stage 2-3 node-positive breast cancer who became cN0 after NAC with negative nodes on SLNB, axillary nodal recurrence rates were low following both TAD and SLNB alone, despite higher non-retrieval of the clipped node in the SLNB alone group. These findings suggest systemic therapy and adjuvant radiation treatment, and not surgical resection of the known disease, may be the driving force in axillary recurrence.

Learning Objectives:

  • Describe that stage 2-3 node-positive breast cancer patients who become ycn0 after neoadjuvant chemotherapy with negative nodes on SLNB have low axillary recurrence rates after both TAD and SLNB alone.
  • Describe that patients who have sentinel lymph node biopsy alone have higher non-retrieval of clipped node, compared to patients who have a targeted axillary dissection.
  • Describe targeted axillary dissection compared to sentinel lymph node biopsy alone.