Prognostic value and interobserver agreement of endoscopic ultrasonography for superficial squamous cell carcinoma of the esophagus: a prospective study

Accuracy of endoscopic ultrasound in preoperative staging of early esophageal cancer: A Meta-analysis

AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) in the preoperative staging of early esophageal cancer.

METHODS: We searched the Medline, PubMed, Web of Science, Embase, Cochrane Central Trials, Wanfang, CBM, CNKI and VIP databases for relevant studies published. Study selection, quality assessment and data extraction were performed by two reviewers independently. Meta-Disc (version1.4) software was used to perform the meta-analysis for sensitivity, specificity, positive likelihood ratio (LR), and negative LR. Pooling results were derived (by) using the fixed-effect model when significant heterogeneity was not present, and the random-effect model was applied otherwise. A summary receiver-operating characteristic (SROC) curve was constructed. Furthermore, to explore the potential sources of heterogeneity, we used meta-regression to estimate the effect of the characteristics of the studies on the diagnostic accuracy of EUS. In addition, the outliers were identified by the method described by Deville and a subgroup analysis was performed by excluding the outliers. We used Stata statistical software (version 10.0) to assess the publication bias using the Begg-Mazumdar indictor and Harbord-Egger indictor.

RESULTS: Twenty studies with a total of 1115 patients were included in this analysis. The pooled sensitivity, specificity, and positive and negative likelihood ratio of EUS for T1m staging were 0.85 (95%CI: 0.83-0.88), 0.86 (95%CI: 0.83-0.89), 5.34 (95%CI: 3.67-7.76), and 0.21 (95%CI: 0.15-0.29), respectively. For stage T1sm, these results were 0.87 (95%CI: 0.84-0.90), 0.85 (95%CI: 0.82-0.88), 4.64 (95%CI: 3.47-6.22), and 0.18 (95%CI: 0.13-0.25). For stage N, these results were 0.71 (95%CI: 0.61-0.80), 0.78 (95%CI: 0.71-0.84), 2.93 (95%CI: 1.49-5.79), and 0.46 (95%CI: 0.18-1.22). The percent of area under the curve was 92.1% for both stage T1m and stage T1sm, and 80% for stage N. No significant publication bias was found with either the Begg-Mazumdar indictor (P = 0.216) or the Harbord-Egger indictor (P = 0. 412).

CONCLUSION: EUS has excellent sensitivity and specificity in diagnosing the T1 stage of early esophageal cancer. However, the frequency of EUS probe and the experience of the endosonographers can affect the diagnostic accuracy of EUS. EUS plays an important role in clinical selection of surgical approaches and treatments.