Background: The utility of axillary lymph node dissection after sentinel lymph node biopsy has been called into question. We sought to determine the sensitivity, specificity, and accuracy of axillary ultrasound and fine-needle aspiration biopsy (FNAB) in the identification of axillary nodal metastasis in early breast cancer patients.
Methods: Data of patients with stage I and II breast cancer who underwent surgery and staging were reviewed. Axillary ultrasound findings were assessed and lymph node status recorded after axillary dissection. The data were cross-tabulated, and test characteristics were calculated.
Results: Of 235 patients, none demonstrated more than 2 positive sentinel lymph nodes. Ductal carcinoma was present in 68%, estrogen and progesterone receptors were positive in 81 and 64%, respectively, Her-2/neu was positive in 10%, and 36% were axillary node positive. The sensitivity and specificity of ultrasound alone were 55 and 88%, respectively. Predictors of abnormal ultrasound included size of metastasis, estrogen receptor and Her-2 status, tumor grade, and presence of lymphovascular invasion. Addition of FNAB increased the sensitivity and specificity to 69 and 100%. In conjunction with FNAB, the positive and negative predictive values were 100 and 54%, respectively. Ten percent of patients with nodal metastases demonstrated a positive FNAB. Patients with a positive FNAB did not harbor more nodal metastases or a greater proportion of gross extranodal disease compared to patients not subjected to FNAB.
Conclusions: Axillary ultrasound with FNAB has an accuracy of >70% in this series. It is easily performed and may avoid unnecessary sentinel lymph node biopsy in a significant number of patients.