Omitting Sentinel Lymph Node Biopsy after Neoadjuvant Systemic Therapy for Clinically Node Negative HER2 Positive and...

Area of Science:

• Oncology
• Surgical Oncology
• Breast Cancer Research

Background:

• Systemic therapies for breast cancer are increasingly tailored to tumor subtypes.
• Neoadjuvant systemic therapy (NAST) improves pathologic complete response (pCR) rates, enabling surgical de-escalation.
• Triple-negative breast cancer (TNBC) and HER2-positive breast cancer show high response rates to NAST.

Purpose of the Study:

• To determine the rate of axillary lymph node positivity (ypN+) after NAST in clinically node-negative (cN0) patients with TNBC or HER2-positive breast cancer who achieved a complete response.
• To evaluate the feasibility of omitting sentinel lymph node biopsy (SLNB) in this select patient population.

Main Methods:

• A pooled analysis of five studies involving 3834 patients.
• Inclusion criteria: TNBC or HER2-positive breast cancer, initially cN0, and achieving radiological complete response (rCR) and/or pCR after NAST.
• Systematic literature search of MedLine.

Main Results:

• The pooled rate of sentinel node positivity (ypN+) was 2.16% (95% CI: 1.70-2.63).
• This rate is significantly lower than the accepted false-negative rate for SLNB.
• Achieving rCR and/or pCR in the breast after NAST is associated with a low likelihood of nodal metastasis.

Conclusions:

• Omission of SLNB may be considered for patients with TNBC or HER2-positive breast cancer who are initially cN0 and achieve a complete response to NAST.
• This approach could reduce surgical morbidity without compromising oncologic safety.
• Further clinical validation is warranted to refine patient selection criteria for axillary surgery omission.