The value of ultrasound elastography in differential diagnosis of superficial lymph nodes

The study evaluated the value of ultrasound elastography in differentiating the benign and malignant superficial lymph nodes. A total of 112 subjects, including 82 patients with enlarged lymph nodes and 30 healthy volunteers, were recruited. All the subjects were examined by B-mode ultrasonography, power Doppler ultrasonography and elastography. Most of the patients were histopathologically confirmed by needle aspiration cytology and some patients were diagnosed by clinical data combined with follow-up findings. The sensitivity, specificity and accuracy of B-mode ultrasonography were 59.8%, 76.5% and 67.1%, those of the blood flow classification by power Doppler ultrasonography 77.0%, 82.3% and 79.4% and those of elastographic classification 74.7%, 97.1% and 84.5%, respectively. The elasticity of the lymph nodes was quantitatively measured and defined as stiffness value. When the stiffness value of 2.395 was taken as the cutoff point, the sensitivity and specificity of elastography were 78.41% and 98.51%, and the Youden index reached the highest, with the value being 0.7692. The stiffness values of two indeterminate benign lymph nodes, the elastrographic findings of which were rated as patterns 2 and 3, were below the cutoff point. The elastographic findings of 10 malignant lymph nodes were also classified as pattern 2 or 3. Only one of them had the stiffness values below the cutoff point. It was concluded that ultrasound elastography is a novel, noninvasive and convenient tool for the differentiation of the nature of the superficial lymph nodes in clinical practice.