Accuracy of endoscopic ultrasound in staging and restaging patients with locally advanced rectal cancer undergoing neoadjuvant chemoradiation

Abstract

Background: To date, the role of endoscopic ultrasound (EUS) in restaging locally advanced rectal cancer (LARC) after neoadjuvant chemoradiotherapy (NAT) have not been thoroughly investigated.

Aim: To evaluate accuracy and clinical usefulness of EUS for both staging and restaging LARC.

Methods: According to EUS staging, patients with LARC were enrolled in the study. Those who underwent surgery directly represented a control group useful for evaluating the accuracy of EUS in staging LARC. In the study group, EUS was repeated seven weeks after NAT, before surgery. The results of EUS were compared with the corresponding pTN stages.

Results: From 2000 to 2006, 212 consecutive patients with RC underwent EUS staging. Among them EUS diagnosed 162 LARC (M/F = 93/69; mean age: 60 years [range 40-80]). The final study group included 85 patients with LARC. EUS restaging had an overall accuracy of 61% and 59% for T and N-stage, respectively. In the control group, the accuracy of EUS in staging LARC was 86% and 58% for T and N-stage, respectively.

Conclusion: EUS accurately stages LARC and enables appropriate decision-making, with selection of those patients who need NAT. On the other hand, EUS restaging of LARC after NAT has low accuracy and should not be used in clinical practice.