Abstract: Background and purpose: Lymphoma and metastatic lymph node can both show volume increase. Real-time shear wave elastography (SWE) can obtain quantitative information of the elastic distribution within the tissue, and reflect hardness of the tissue in different colors. This study aimed to explore the values of SWE in differential diagnosis between lymphoma and metastatic lymph node. Methods: From Apr. 2016 to Mar. 2017, 80 patients with malignant lymphadenopathy of suspected lymphoma and metastatic lymph node in the Peking University Shougang Hospital were selected by reviewing and summarizing research methods. All patients were given conventional ultrasound and SWE diagnosis, and the diagnostic parameters and differential diagnostic value were recorded. Results: In the 80 patients, 40 patients were diagnosed with metastatic lymph nodes, 40 patients were diagnosed with malignant lymphoma. Patients’ lymph nodes in lymphoma group were significantly larger in diameter than those in metastasis group (P<0.05), there was no significant difference in the ratio of length to diameter between the two groups (P>0.05). The average and maximum elastic modulus values of metastasis group were significantly higher than those of lymphoma group (P<0.05). The sensitivity was 95.3% and the specificity was 81.3% when the mean elastic modulus value was 15.80 kPa (as the diagnostic boundary value). The sensitivity was 85.0% and the specificity was 98.8% when the maximum elastic modulus value was 38.35 kPa (as the diagnostic boundary value). The receiver operating characteristic (ROC) curve analysis showed that using the average and maximum elastic modulus values to differentiate metastatic lymph nodes from lymphoma lymph nodes, the area under curve (AUC) values were 0.945 and 0.952, respectively. Conclusion: SWE is of high accuracy in differential diagnosis between metastatic lymph node and lymphoma. It can provide objective and visual information to clinicians with important clinical diagnostic value.

Key words: Real-time shear wave elastography, Differential diagnosis, Lymphoma, Metastatic lymph node