Sentinel node biopsy versus low axillary sampling in women with clinically node negative operable breast cancer

Area of Science:

• Oncology
• Surgical Pathology
• Diagnostic Imaging

Background:

• Sentinel lymph node biopsy (SNB) initially involved excising the first identified axillary lymph node(s) (LN).
• The definition expanded to include palpable nodes near sentinel nodes (SN).
• Lower axillary sampling (LAS) was proposed for improved excision of these nodes.

Purpose of the Study:

• To compare the false negative rates (FNR) of SNB and LAS in predicting axillary LN status.
• To evaluate the accuracy of LAS in staging breast cancer patients.
• To determine if focusing SNB on blue and/or hot nodes (B&/HN) impacts accuracy.

Main Methods:

• 478 women with clinically node-negative operable breast cancer underwent LAS and SNB.
• LAS involved excising fibrofatty tissue below the intercostobrachial nerve after radioactive colloid and blue dye injection.
• The primary endpoint was comparing FNR of SNB versus LAS.

Main Results:

• The FNR for SNB was 12.7% and for LAS was 10.5%, which were not significantly different.
• Excluding palpable nodes and relying solely on B&/HN for SNB resulted in a significantly higher FNR (29.0%).
• LAS demonstrated comparable accuracy to SNB in predicting axillary LN status.

Conclusions:

• LAS is a safe and accurate alternative to SNB for staging axillary lymph nodes in operable breast cancer.
• Limiting SNB to only B&/HN increases the risk of understaging nodal metastasis.
• LAS is an effective, low-cost procedure that can minimize axillary surgery.