Diagnostic Performance of Ultrasound Elastography in Differentiating Benign and Malignant Lymphadenopathy

Abstract

Lymphadenopathy is a common clinical finding associated with a broad spectrum of benign and malignant diseases. Differentiating malignant from benign lymphadenopathy remains an important diagnostic challenge because conventional clinical and sonographic findings may overlap considerably. Histopathological examination remains the reference standard for definitive diagnosis, but tissue sampling is invasive and may be associated with sampling error, particularly when the most representative lymph node is not accurately targeted. Ultrasound elastography provides additional information regarding tissue stiffness and has therefore emerged as a potentially useful adjunct to conventional ultrasound in the assessment of lymph nodes. However, most published evidence originates from populations outside sub-Saharan Africa, where the spectrum of lymph node disease may differ substantially from that encountered in East African tertiary referral hospitals. To determine the diagnostic performance of ultrasound elastography in differentiating benign from malignant lymphadenopathy among patients undergoing lymph node biopsy at Moi Teaching and Referral Hospital (MTRH), Eldoret, Kenya. A hospital-based cross-sectional descriptive study was conducted among 66 patients presenting with lymphadenopathy at the Interventional Radiology Unit of MTRH. Participants referred for ultrasound-guided lymph node core needle biopsy between July 2024 and June 2025 were evaluated. Demographic and clinical characteristics were recorded, followed by ultrasound assessment and elastographic evaluation using a five-point colour-coded scoring system on a Vinno 6 ultrasound machine. Histopathological findings were used as the reference standard. Continuous variables were summarized using means, while categorical variables were summarized using frequencies and percentages. Diagnostic performance was assessed using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) curve analysis. The 66 participants had a mean age of 32.4 ± 20.7 years, with ages ranging from 2 to 75 years. Cervical lymph nodes were the most frequently biopsied nodes, accounting for 40.9% (n=27) of cases. Elastography scores of 4 and 5 predominated, occurring in 59.1% and 28.8% of cases, respectively. Histopathological examination identified 52 (78.8%) malignant and 14 (21.2%) benign lymph nodes. Lymphoma was the most frequent malignant diagnosis, accounting for 45.5% of all histopathological diagnoses. Using histopathology as the reference standard, ultrasound elastography demonstrated a sensitivity of 96.1%, specificity of 42.9%, PPV of 86.2%, and NPV of 75%. The area under the ROC curve was 0.692. Ultrasound elastography demonstrated very high sensitivity but relatively low specificity for malignant lymphadenopathy in this region. The findings support its use as a non-invasive triage and biopsy-targeting adjunct rather than as a replacement for histopathological diagnosis. Local diagnostic protocols incorporating elastography alongside conventional ultrasound and tissue diagnosis may improve prioritization of suspicious lymph nodes and support timely clinical decision-making.