Evaluation of Axillary Involvement by Ultrasound-guided Lymph Node Biopsy: A Prospective Study

Objectives: The primary aim of this prospective study was to evaluate the accuracy of pre-operative ultrasound (US) alone and associated with a fine needle aspiration cytology (FNAC) or a core needle biopsy (CNB) in the diagnosis of axillary node involvement in patient with breast cancer. The secondary study objective was to determine if this US±FNAC or CNB can lead to the adequate axillary surgery in cN0 and cN1 patient.

Methods: A total of 121 consecutive women with stage cT1 to cT2, cN0/cN1, invasive breast cancer were prospectively identified at our institution between February 2, 2013 and August 30, 2013. The sensitivity, specificity, VPP, NPV were calculated, with confidence intervals, using the definitive histological result of the sentinel node biopsy (SLNB) or axillary lymph node dissection (ALND) as the baseline.

Results: Twenty-seven CNB and 2 FNAC were performed. For the whole series, the sensitivity and the specificity of US alone were 48.7% [36-59%] and 89% [83-94%]. For US±FNAC or CNB, the sensitivity and the specificity were 35.9% [26-38%] and 98.8% [94-100%]. Seven women with cN1 clinical examination had SLNB, which permit to decrease the number of ALND of 16.3%. It would have avoided unnecessary SLNB, prompting immediate ALND in 9 patients with cN0 axillae, which means a reduction of SLNB of 8.6%. US±FNAC or CNB lead to the adequate surgery in 72.7% of cases.

Conclusion: US±CNB or FNAC is also a relatively efficient and safe test and should be considered routinely. It allowed triaging patients to the well axillary surgery (SLNB or ALND).