Accuracy of Endorectal Endoscopic Ultrasound (EUS) for Locally Advanced Rectal Cancer (LARC) Restaging After Neoadjuvant Chemoradiotherapy (NAT): A Meta-Analysis.

Background/aims: Endorectal endoscopic ultrasound (EUS) can provide accurate and reliable information for initial staging of locally advanced rectal cancer (LARC) in both the depth of rectal cancer penetration (T-stage) and regional lymph node involvement (N-stage). However, there is still no consensus about its accuracy in retagging LARC after neoadjuvant chemoradiotherapy (NAT).

Methodology: In this study, we retrieved previous studies and performed a meta-analysis for assessing the accuracy of EUS for retagging of LARC after NAT.

Results: It was found the accuracy of EUS for T restaging of LARC was relatively low and over-staging was common, although the accuracy for assessing T3/4 was significantly higher than T0-T2 stage. The specificity of EUS for assessing N stage was relatively high, but the sensitivity was relatively low.

Conclusions: Data obtained in this study confirmed the overall accuracy of EUS is not sufficient to serve as a basis for decisions on restaging Exploring the possible application of new techniques is necessary for better restaging.