Endoscopic Ultrasound for Preoperative Esophageal Squamous Cell Carcinoma: a Meta-Analysis

BACKGROUND Treatment options and prognosis of esophageal squamous cell carcinoma (ESCC) depend on the primary tumor depth (T-staging) and regional lymph node status (N-staging). Endoscopic ultrasound (EUS) has emerged as a useful staging tool, but studies regarding its benefits have been variable. The objective of this study was to evaluate the diagnostic accuracy of EUS for detecting preoperative ESCC. METHODS We included in our meta-analysis studies involving EUS-based staging of preoperative ESCC compared with pathological staging. Using a random-effects model, we performed a meta-analysis of the accuracy of EUS by calculating pooled estimates of sensitivity, specificity and the diagnostic odds ratio. In addition, we created a summary receiver operating characteristic (SROC) curve. RESULTS Forty-four studies (n = 2880) met the inclusion criteria. The pooled sensitivity and specificity of T1 were 77% (95%CI: 73 to 80) and 95% (95%CI: 94 to 96). Among the T1 patients, EUS had a pooled sensitivity in differentiating T1a and T1b of 84% (95%CI: 80 to 88) and 83% (95%CI: 80 to 86), and a specificity of 91% (95%CI: 88 to 94) and 89% (95%CI: 86 to 92). To stage T4, EUS had a pooled sensitivity of 84% (95%CI: 79 to 89) and a specificity of 96% (95%CI: 95 to 97). The overall accuracy of EUS for T-staging was 79% (95%CI: 77 to 80), and for N-staging, 71% (95%CI: 69 to 73). CONCLUSIONS EUS has good diagnostic accuracy for staging ESCC, which has better performance in T1 sub-staging (T1a and T1b) and advanced disease (T4).