Diagnostic accuracy of endoscopic ultrasound and intraductal ultrasonography for assessment of ampullary tumors: a meta-analysis

Accurate preoperative assessment of ampullary tumors (ATs) is critical for determining the appropriate treatment. The reported diagnostic accuracy of endoscopic ultrasound (EUS) and intraductal ultrasonography (IDUS) for detecting tumor depth (T-staging) and regional lymph node status (N-staging) varies across studies.An electronic search of the MEDLINE and Embase databases was conducted to identify studies that assessed the diagnostic accuracy of EUS and IDUS for ATs. Sensitivities and specificities of eligible studies were summarized using either fixed effects or random-effects model.Twenty-one studies were included in the final analysis. The pooled sensitivity and specificity of EUS were 0.89 and 0.87 for T1, 0.76 and 0.91 for T2, 0.81 and 0.94 for T3 and 0.72 and 0.98 for T4, respectively. For IDUS, estimates from five studies were 0.90 and 0.88 for T1, 0.73 and 0.91 for T2 and 0.79 and 0.97 for T3, respectively. For N-staging, 16 studies using EUS were included with sensitivity and specificity of 0.61 and 0.77, respectively. Moreover, estimates of IDUS for N-staging were 0.61 and 0.92, respectively.Our results imply that EUS and IDUS have good diagnostic accuracy for T-staging of ATs. However, the accuracy of EUS or IDUS is less satisfactory for N-staging. More well-designed prospective studies are warranted to confirm our findings.