Efficacy of physical examination, ultrasound, and ultrasound combined with fine-needle aspiration for axilla staging of primary breast cancer

The aim of this study was to compare the efficacy of physical examination (PE), ultrasound (US), and US combined with fine-needle cytology (US-FNAC) in evaluation of node status before sentinel lymph node biopsy (SLNB) for breast cancer patients. We performed a retrospective study of 3,781 breast cancer patients and calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for PE, US, and US-FNAC, respectively. A total of 3,175 cases were documented as cN₀ and 606 as cN₁. Abnormal axillary nodes under US were detected in 1,152 cases, among which 821 were proven to have positive nodes by FNAC. The positive FNAC results enabled 11.7 % of cN₀ patients (373/3,175) to avoid unnecessary SLNB. All 331 cases with abnormal US but negative FNAC results, and the 2,629 cases with normal US underwent SLNB procedure for nodal staging, and metastatic nodes were identified in 745 patients. The sensitivity of PE was 32.2 %, with a specificity of 95.5 %, a PPV of 83.5 %, a NPV of 65 %, and an accuracy of 69.3 %. The sensitivity, specificity, PPV, NPV, and accuracy of axillary US alone were 58.6, 89.4, 79.6, 75.3, and 76.7 %, respectively. Combining axillary US with FNAC resulted in sensitivity, specificity, PPV, NPV, and accuracy of 52.4, 100, 100, 74.8, and 80.3 %, respectively. Our study demonstrated that US-FNAC is a feasible and effective triage during axillary staging for newly diagnosed breast cancer patients.