Preoperative Ultrasound-guided Core Biopsy of Axillary Nodes for Staging of Clinically Negative Axilla in Breast Cancer Patients – A Pilot Study

Objective The aim of the current study is to determine the feasibility and accuracy of ultrasound-guided core biopsy for staging the axilla in clinically node-negative patients with invasive breast cancer. Introduction Historically, in breast cancer patients, axillary lymph node dissection was performed to stage axilla. Because of the high morbidity of axillary lymph node dissection, sentinel lymph node biopsy (SLNB) became the standard of care in patients with clinically node-negative breast cancer. However, SLNB is expensive, time consuming, can cause morbidity and can be complicated by seroma formation, sensory nerve injury, lymphedema, etc. Many centers rely on the availability of frozen section on sentinel lymph nodes to avoid a second procedure with the accuracy of procedure ranging from 73 to 96%, however, the availability of frozen section is limited in our part of the world. Pre-operative identification of axillary node positivity in patients with clinically negative nodes by ultrasound imaging of the axilla would allow one-stage axillary clearance and can decrease the need for SLNB from 21% to 70%. The aim of the present study is to determine the accuracy and feasibility of ultrasound-guided core biopsy to stage the axilla in clinically node-negative breast cancer patients, comparing with final histopathology as gold standard. Material & methods This was a non-randomized, prospective interventional study, done at Radiology Department of Aga Khan University Hospital. All patients diagnosed with breast cancer (histologically proven) with clinically negative axilla and ipsilateral positive axillary ultrasound were included. These patients underwent axillary lymph node core biopsy. If the result was negative they were subjected to SLNB. Histopathology result was taken as gold standard. Results The sensitivity of ultrasound-guided core biopsy was 88%, specificity 100%, positive predictive values (PPV) 100%, negative predictive values (NPV) 89.28%, diagnostic accuracy 94%. Conclusion In conclusion, the present study demonstrated high accuracy of ultrasound-guided axillary lymph node core biopsy in breast cancer patients with clinically node-negative axilla. Positive core biopsy results can thus obviate the need for sentinel lymph node biopsy and allow breast surgeons to directly proceed to axillary lymph node dissection.