EUS elastography for the differentiation of benign and malignant lymph nodes: a meta-analysis

Background: EUS elastography is a new technique for differentiating benign and malignant lymph nodes (LNs) by describing the mechanical property of the target tissue. Objective: To assess the accuracy of EUS elastography by pooling data of existing trials. Design: Seven studies involving 368 patients with 431 LNs were included. Meta-analysis was performed. Pooling was conducted in a fixed-effect model or a random-effect model. Patients: This study involved 368 patients. Intervention: EUS elastography. Main Outcome Measurements: Meta-analysis and meta-regression analysis. Results: The pooled sensitivity of EUS elastography for the differential diagnosis of benign and malignant LNs was 88% (95% confidence interval [CI] 0.83-0.92), and the specificity was 85% (95% CI, 0.79-0.89). The area under the curve under summary receiver operating characteristic (SROC) was 0.9456. The pooled positive likelihood ratio was 5.68 (95% CI, 2.86-11.28), and the negative likelihood ratio was 0.15 (95% CI, 0.10-0.21). The subgroup analysis by excluding the outliers provided a sensitivity of 85% (95% CI, 0.79-0.90) and a specificity of 91% (95% CI, 0.85-0.95) for the differential diagnosis of benign and malignant LNs. The area under the curve under SROC was 0.9421. Limitations: A small number of studies met inclusion criteria. Conclusion: EUS elastography is a promising, noninvasive method for differential diagnosis of malignant LNs and may prove to be a valuable supplemental method to EUS-guided FNA. (Gastrointest Endosc 2011;74:1001-9.)