A systematic review of the staging performance of endoscopic ultrasound in gastro-oesophageal carcinoma

BACKGROUND—Endoscopic ultrasound (EUS) may be used for preoperative staging of gastro-oesophageal carcinoma but performance values given in the literature differ. AIMS—To identify and synthesise findings from all articles on the performance of EUS in tumour, node, metastasis (TNM) staging of gastro-oesophageal carcinoma. SOURCE—Published and unpublished English language literature, 1981-1996. METHODS—Data on the staging performance of EUS were retrieved and evaluated. Summary receiver operator characteristic methodology was used for synthesis, and a summary estimate of performance, Q*, obtained. Multiple regression analysis was used to assess study validity and investigate reasons for differences in performance. RESULTS—Twenty seven primary articles were assessed in detail. Thirteen supplied results for staging oesophageal cancer, 13 for gastric cancer, and four for cancers at the gastro-oesophageal junction. For gastric T staging, Q*=0.93 (95% confidence interval (CI) 0.91-0.95) and for oesophageal T staging, Q*=0.89 (95% CI 0.88-0.92). For gastro-oesophageal T staging, including cancers at the gastro-oesophageal junction, Q*=0.91 (95% CI 0.89-0.93). Inclusion of cases with non-traversable stenosis was found to slightly reduce staging performance. For N staging, Q*=0.79 (95% CI 0.75-0.83). In articles that compared EUS directly with incremental computed tomography, EUS performed better. None of the variables assessed in the regression analysis was significant using a Bonferroni correction. Three variables (anatomical location, traversability, and blinding) showed strong relationships for future research and validation. CONCLUSIONS—EUS is highly effective for discrimination of stages T1 and T2 from stages T3 and T4 for primary gastro-oesophageal carcinomas. The failure rate of EUS from non-traversability of a stenotic cancer may be a limitation in some patient groups. Keywords: endoscopic ultrasound; gastro-oesophageal cancer; TNM staging; systematic literature review; meta-analysis