Sensitivity and Specificity of Preoperative Ultrasonography for Diagnosing Nodal Metastases in Patients with Breast Cancer

Abstract

Rational therapy planning should aim to minimize the rate of axillary lymph node dissection (ALND) in patients without metastatic disease. By the same token, the frequency of sentinel lymph node biopsies (SLNB) should not be unnecessarily high in patients with axillary node disease. Preoperative axillary ultrasonography is a generally available noninvasive technique for assessing nodal status. Based on retrospective data, we analyzed the sensitivity, specificity, positive and negative predictive value, and efficiency of preoperative ultrasonography US. A total of 429 axillary ultrasonographic examinations were included, and the management decisions were based on the ultrasonographic findings. Patients with suspicious US results were scheduled for ALND, while patients with unremarkable findings underwent SLNB. Axillary metastases were found in 146 of 429 (34 %) cases. In 75 of 429 (17 %) axillary examinations, ultrasonography revealed suspicious findings. In these cases, we proceeded with ALND, thereby reducing the number of SLNB by 17 %. 219 of 429 cases were classified correctly as not having metastasis, thus lowering the rate of ALND, which is associated with higher postoperative morbidity, by 51 %. Preoperative ultrasonography had a sensitivity of 53.6 %, specificity of 75.5 %, and a positive predictive value of 77.3 %. The negative predictive value was 51.3 % and the efficiency was 68.5 %. Ultrasonography is a moderately sensitive, but quite specific, preoperative method for assessing the axillary lymph nodes.