Background: Assessing the validity and clinical utility of axillary ultrasonography (AUS)-guided fine needle aspiration biopsy (FNAB) in detection of nodal metastasis during preoperative axillary investigation in comparison to the histopathologic diagnosis in early-stage breast cancer.
Methods: A total of 279 operated primary breast cancer patients (age: 55.3 ± 12.8, ranged 17-90 years) were included. Data on AUS findings at the time of initial diagnosis (first look AUS), second-look AUS findings performed by the breast radiologist during breast biopsy procedure and the AUS-guided FNAB findings were evaluated with respect to the final histopathology report obtained through axillary surgery via sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection (ALND). The diagnostic performance of each method in detecting metastatic ALNs were compared in terms of sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV).
Results: The sensitivity, specificity, and accuracy of the first look AUS in detecting nodal metastasis were 64.56%, 86.78%, and 74.19% while the PPV and NPV were 86.44% and 65.22%, respectively. The sensitivity, specificity, and accuracy of the second-look AUS were 70.25%, 87.60%, and 77.78%, while PPV and NPV were 88.10% and 69.28%, respectively. The sensitivity, specificity, and accuracy of the second-look AUS guided FNAB were 89.19%, 73.33%, and 87.30%, while the PPV and NPV were 96.12% and 47.83%, respectively. The consideration of second-look AUS and finding of nodal metastasis in FNAB was associated with significantly higher likelihood of ALND (55.4% vs. 44.6%, p < 0.001) and lower likelihood of SLNB (34.7% vs. 65.3%, p < 0.001) compared to consideration of nonmetastatic ALN status. In 23 (22.3%) patients with positive findings on AUS-guided FNAB, SLNB was applied; 21 had positive results after surgical dissection, indicating that nearly 20% of patients had unnecessary SLNB.
Discussion: US-guided FNAB of suspicious ALNs is a simple, minimally invasive, and highly effective method for preoperative axillary staging in patients with invasive breast cancer avoiding the more invasive method SLNB and it enables the surgeon to proceed directly to ALND in positive cases.
Keywords: Axillary ultrasonography; axillary dissection; breast cancer; fine needle aspiration biopsy; sentinel lymph node biopsy.