Role of high resolution ultrasound/endosonography and elastography in predicting lymph node malignancy

OBJECTIVE: The objective of this study is to evaluate the role of high resolution ultrasonography (US) and endoscopic ultrasound (EUS)-elastography in predicting malignant lymphadenopathy. PATIENTS AND METHODS: This prospective study included 88 patients who underwent EUS or US examination of different groups of lymph nodes (LNs). The classification as benign or malignant based on the real time elastography pattern and the B-mode US/EUS images was compared with the final diagnosis obtained by EUS or US guided fine-needle aspiration cytology (FNAC), tru-cut biopsy or excisional biopsy and follow-up in benign lesions not indicated for biopsy for at least 12 months. RESULTS: Regarding the echogenicity, 98.3% of the benign LNs were hyperechoic, 1.7% was hypoechoic while 89.7% of the malignant LNs were hypoechoic, 3.4% were heterogenous and 6.9% were hyperechoic. With cut-off value of 1.93, the sensitivity of longitudinal to transverse ratio was 73% and the specificity was 100%. Score 1 elastography had specificity of 100% in diagnosis of benign LNs, sensitivity was 76.3%, positive predictive value (PPV) was 100%, negative predictive value (NPV) was 84.7% while score 2 had a sensitivity of 60%, specificity of 31.5%, PPV of 15.3%, NPV of 79.3%. Score 3 had a sensitivity of 70.2%, specificity of 100%, PPV of 13.8%, NPV of 100% in detecting malignancy while score 4 had a sensitivity of 85.5%, specificity of 100%, PPV of 100%, NPV of 65.5%. CONCLUSION: Elastography is a promising diagnostic modality that may complement standard ultrasound and EUS and help guide FNAC during staging of LNs.