Objectives: This study aimed at exploring the role of ultrasound (US) elastography in the diagnosis of the axillary lymph node status in patients with breast cancer.
Methods: We analyzed 140 visible axillary lymph nodes on conventional US imaging. All of them underwent elastography. Five conventional US features were adopted to assess axillary lymph nodes: longitudinal diameter, longitudinal-to-transverse diameter ratio, cortical thickness, status of the hilum, and vascular pattern. As for elastography, the proportion of the hard area within each lymph node was estimated visually. The lymph node was defined as positive on elastography when the proportion was 50% or greater. Meanwhile, disjunctive and conjunctive combinations of US and elastography were adopted to evaluate the lymph nodes. The histopathologic diagnosis was regarded as the reference standard.
Results: The sensitivity, specificity, and accuracy were 76.92%, 87.10%, and 81.43%, respectively, for conventional US and 84.62%, 83.87%, and 84.29% for the disjunctive combination. The conjunctive combination had specificity of 100% and a positive predictive value of 100%, whereas the sensitivity was low.
Conclusions: Elastography can improve the sensitivity when disjunctively combined with conventional US for diagnosis of the axillary lymph node status. Despite the low sensitivity, the conjunctive combination of US and elastography can improve the positive predictive value on a large scale. Elastography is a useful adjuvant tool in addition to conventional US for the preoperative assessment of axillary lymph nodes in patients with breast cancer.
Keywords: axillary lymph nodes; breast cancer; elastography; ultrasound.
© 2018 by the American Institute of Ultrasound in Medicine.