Endoscopic ultrasound guided fine needle aspiration for the diagnosis of intra-abdominal lymphadenopathy: a systematic review and meta-analysis

Background: It is difficult to diagnose the cause of abdominal lymphadenopathy without determining the primary lesions. With the advent of curved ultrasound endoscopy, EUS-FNA can sample lymph nodes safely, accurately and conveniently. Due to the lack of formal quantitative and comprehensive literature review to determine the diagnostic value of EUS-FNA in the diagnosis of enlarged intra-abdominal lymph nodes of unknown origin, we conducted this study to systematically evaluate the diagnostic accuracy of EUS-FNA in the enlarged intra-abdominal lymph nodes. Methods: We performed a systematic review and meta-analysis to evaluate the accuracy of EUS-FNA for the diagnosis of intra-abdominal lymphadenopathy. We searched PubMed, Embase, and Cochrane Library to collect related studies and diagnostic performance data. We used a random-effects model to estimate the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio (DOR). Heterogeneity was assessed by subgroup and meta-regression analysis. Results: Twelve eligible studies involved 774 patients were identified. The pooled sensitivity and specificity of all studies is 94% (95% CI: 91% to 96%) and 98% (95% CI: 96% to 99%), respectively. The pooled positive and negative likelihood ratios are 17.44 (95% CI, 6.50 to 46.79) and 0.09 (95% CI: 0.06 to 0.14). The pooled DOR is 277.82 (95% CI, 97.65 to 790.46). Conclusions: EUS-FNA is a safe and feasible technique with high sensitivity and specificity for the diagnosis of abdominal lymph node enlargement. Considering the limitations and heterogeneity, high-quality studies are needed to further explore the diagnostic value of EUS-FNA.