Staging accuracy of ampullary tumors by endoscopic ultrasound: Meta-analysis and systematic review

Background and Aim: Accurate preoperative staging of ampullary neoplasms is of paramount importance in predicting prognosis and determining the most appropriate therapeutic approach. The aim of the present review was to evaluate the accuracy of endoscopic ultrasound (EUS) in predicting depth of ampullary tumor invasion (T-stage) and regional lymph node status (N-stage) by carrying out a meta-analysis of all relevant studies. Methods: We systematically searched PubMed, Medline and Scopus databases for all studies published between January 1980 and December 2012. Only EUS studies involving >= 10 patients with ampullary neoplasms, confirmed by surgical histopathology, with data available for construction of a 2 x 2 table were included. Results: Meta-analysis of 14 studies involving 422 patients using the Mantel-Haenszel method was performed. Pooled sensitivity and specificity of EUS to diagnose T1-stage tumor were 77% (95% CI: 69-83) and 78% (95% CI: 72-84), respectively. Pooled sensitivity for T4 tumors was 84% (95% CI: 73-92) and specificity was 74% (95% CI: 63-83). Combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio for diagnosing nodal status were 0.70 (95% CI: 0.62-0.77), 0.74 (95% CI: 0.67-0.0.80), 2.49 (95% CI: 1.91-3.24), 0.46 (95% CI: 0.36-0.59) and 6.53 (95% CI: 3.81-11.19), respectively. Conclusion: Based on our pooled estimates, EUS had a moderate strength of agreement with histopathology in preoperative staging of ampullary neoplasms in predicting tumor invasion and lymph node involvement. Additional refinement in EUS technologies and diagnostic criteria may be required to enhance staging accuracy.