Role of Sonography and Sonoelastography in Characterisation of Cervical Lymphadenopathy with Pathological Association: A Cohort Study

Abstract

Introduction: Identification of the nature of lymph nodes is one of the most important parameters for diagnosis in any oncological setting. The lymph nodes help in staging and this directly affects the prognostic outcome and treatment decision. Ultrasound is the preferred imaging method for distinguishing between benign and malignant superficial lymph nodes given ease of availability and its low cost. However, there is no reliable and definitive sonographic criterion in ultrasound to categorise lymph nodes as benign or malignant. Aim: To evaluate the role of sonography and sonoelastography in characterisation of cervical lymphadenopathy and to associate the imaging findings with cytopathology. Materials and Methods: This was a cohort study, conducted over a period of one year in Teerthankar Mahaveer Medical College and Research Centre, Moradabad, Uttar Pradesh, India, constituting a total of 60 patients with enlarged cervical lymph nodes and evaluated on B-mode ultrasound and elastography in this study. The ultrasonography was performed using either Acuson S3000 ultrasound system (Siemens Medical Solutions, Mountain View, CA) with a 4 to 9 MHz linear transducer for conventional sonography and Acoustic Radiation Force Impulse (ARFI) imaging. Results of radiological findings were tabulated, evaluated and collated with pathological findings. Results: ARFI imaging displayed a sensitivity and specificity of 80% and 97.5% respectively with a Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of 94.1% and 90.7% respectively in distinguishing malignant from benign cervical lymphadenopathy with the diagnostic accuracy being 91.67%. Using Area Under the Receiver Operating Characteristic (ROC) Curve (AUC) of 0.925, a cut-off value for shear wave velocity of 2.98 m/s was obtained. Conclusion: ARFI is a novel technique which can be used to characterise the nature of cervical lymph nodes. Present study demonstrated high diagnostic accuracy (91.67%) in comparison with histopathological findings, ARFI elastography may help in distinction of benign from malignant nodes in adjunct to the grey scale.