Clinical Scorecard: Evaluation of Axillary Pathological Complete Response and Imaging Diagnostic Performance Following Neoadjuvant Chemotherapy in Breast Cancer: A Retrospective Single-Center Analysis

At a Glance

Key Highlights

• HER2-positive and progesterone receptor (PR)-negative tumors have higher rates of axillary pCR after NACT.
• Luminal A and B breast cancer subtypes show lower axillary response rates compared to HER2-rich and triple-negative subtypes.
• PET-CT and ultrasonography (USG) demonstrate high specificity (91.2% and 84.6%, respectively) but modest sensitivity in detecting residual axillary metastasis post-NACT.

Guideline-Based Recommendations

Diagnosis

• Use cytological confirmation of axillary metastasis by fine-needle aspiration biopsy before NACT.
• Employ imaging modalities such as USG, mammography, MRI, and PET-CT to assess axillary lymph node status after NACT.

Management

• Perform sentinel lymph node biopsy (SLNB) in patients with clinical or radiologic complete axillary response after NACT.
• Conduct level I–II axillary dissection (AD) in patients with positive SLNB post-NACT.
• Consider targeted axillary dissection (TAD) with clip placement in biopsy-proven metastatic nodes before NACT to reduce false-negative rates.

Monitoring & Follow-up

• Use imaging modalities as complementary tools to pathological staging due to their modest sensitivity.
• Carefully evaluate PR-positive and HER2-negative tumors for axillary residual disease given lower pCR likelihood.

Risks

• False-negative rates in SLNB can be minimized by dual-tracer technique and excision of at least three sentinel lymph nodes.
• Clip migration or non-visualization may limit the effectiveness of TAD.

Patient & Prescribing Data

Patients with biopsy-proven node-positive breast cancer undergoing NACT, including HER2-positive patients receiving anti-HER2 therapy.

Anthracycline- and taxane-based chemotherapy regimens are standard; anti-HER2 targeted therapy is added for HER2-positive disease; immunotherapy was not routinely used for triple-negative breast cancer during the study period.

Clinical Best Practices

• Select patients for SLNB after NACT based on clinical and radiologic complete axillary response.
• Use dual-tracer SLNB and excise at least three sentinel lymph nodes to reduce false-negative rates.
• Interpret imaging findings in conjunction with pathological assessment to guide axillary management decisions.
• Recognize tumor subtype-specific response patterns to NACT to inform prognosis and surgical planning.

References

• ACOSOG Z0011 trial on axillary dissection
• Studies on imaging prediction of axillary response
• Targeted axillary dissection technique and outcomes