Cervical Lymph Node Imaging Reporting and Data System for Ultrasound of Cervical Lymphadenopathy: A Pilot Study

OBJECTIVE. The objective of our study was to compare ultrasound (US) and real-time elastography (RTE) features of benign and malignant cervical lymphadenopathies and propose a structured reporting system for lymph nodes. MATERIALS AND METHODS. The study population for this retrospective study consisted of 291 consecutive patients who underwent US-guided biopsies for cervical lymphadenopathy between 2013 and 2014. The following imaging features were analyzed: shape, margin, echogenicity, echogenic hilum, gross necrosis, calcification, matting, intranodal vascular pattern, elasticity scores (four categories), and strain ratio. A score was assigned for each significant factor from a logistic regression analysis and was multiplied by the beta coefficient. The fitted probability of malignancy was calculated. The risk of malignancy was determined on the basis of the number of suspicious features. Interobserver agreement of the imaging features was retrospectively analyzed using a coefficient of interrater agreement. RESULTS. The imaging features that were significantly associated with malignant lymphadenopathy were round shape, noncircumscribed margin, hyperechogenicity, absence of hilum, gross necrosis, calcification, peripheral or mixed vascularity, high elasticity scores, and high level of strain ratio (p < 0.05). The fitted probability and risk of malignancy increased as the number of suspicious features increased. The risk of malignancy according to the Cervical Lymph Node Imaging Reporting and Data System categories was as follows: category 1, 3.3%; category 2, 10.9%; category 3, 26.7%; category 4, 51.8-74.4%; and category 5, 90.6-98.8%. An analysis of the overall interobserver agreement revealed that interobserver agreement was moderate to good. CONCLUSION. We propose the Cervical Lymph Node Imaging Reporting and Data System, which uses the number of suspicious US and RTE features to assess the risk of malignancy in cervical lymph nodes.