Role of high resolution ultrasonography/endoscopic ultrasonography and elastography in predicting lymph node malignancy

OBJECTIVE: To evaluate the role of high resolution ultrasonography (US) and endoscopic ultrasonography (EUS)-elastography in predicting malignant lymphadenopathy. 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 to 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% were 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.