Sentinel lymph node surgery after neoadjuvant chemotherapy in patients with node-positive breast cancer: the ACOSOG...

Area of Science:

• Oncology
• Surgical Oncology
• Breast Cancer Research

Background:

• Sentinel lymph node (SLN) surgery is a less invasive staging method than axillary lymph node dissection (ALND) for node-negative breast cancer.
• Its utility in node-positive (cN1) breast cancer patients who receive neoadjuvant chemotherapy is uncertain due to potentially high false-negative rates (FNRs).

Purpose of the Study:

• To determine the FNR of SLN surgery following neoadjuvant chemotherapy in women initially presenting with biopsy-proven node-positive (cN1) breast cancer.
• To evaluate if the FNR in patients with at least two examined SLNs exceeds 10%.

Main Methods:

• The ACOSOG Z1071 trial enrolled 756 women with cN1 breast cancer receiving neoadjuvant chemotherapy.
• Patients subsequently underwent both SLN surgery and ALND.
• SLN identification utilized blue dye and/or radiolabeled colloid mapping.

Main Results:

• In 663 evaluable patients, the SLN FNR was 12.6% (90% Bayesian credible interval, 9.85%-16.05%) when at least two SLNs were removed.
• A complete pathological nodal response was observed in 41.0% of patients.
• SLNs were not identified in 7.1% of patients, and only one SLN was excised in 12.0%.

Conclusions:

• The FNR for SLN surgery in cN1 breast cancer patients after neoadjuvant chemotherapy was 12.6%, which is higher than the 10% threshold.
• Current SLN surgery approaches require modification or refined patient selection to be a reliable alternative to ALND in this population.