Ultrasound-Guided Aspiration Biopsy for Detection of Nonpalpable Axillary Node Metastases in Breast Cancer Patients: New Diagnostic Method

Abstract. This study was designed to evaluate the accuracy of ultrasonography alone and in combination with fine-needle aspiration biopsy (FNAB) for detection of axillary metastases of nonpalpable lymph nodes in breast cancer patients. Ultrasonography was carried out in 150 axillas of 148 patients (mean age 57 years, range 30–80 years); and in 93 axillas lymph nodes were detected. Nodes were described according to their dimension and echo patterns and were compared with histopathologic results. FNAB was carried out in 81 axillas (122 nodes). The sensitivity of ultrasonography was highest (87%) when size (length >5 mm) was used as criterion for malignancy, but the specificity was rather low (56%). When nodes with a malignant pattern (echo-poor or inhomogeneous) were visualized, specificity was 95%. Ultrasound-guided FNAB had a sensitivity of 80% and a specificity of 100% and detected metastases in 63% of node-positive patients. It is concluded that FNAB is an easy, reliable, inexpensive method for identifying patients with positive nodes. In the case of negative findings, other diagnostic procedures to exclude lymph node metastases, such as sentinel node mapping, could be performed.