The evil lies below the surface: Subsquamous tumor extension in Barrett's adenocarcinoma

A pilot study of the endomicroscopic assessment of tumor extension in Barrett's esophagus-associated neoplasia before endoscopic resection

BACKGROUND AND STUDY AIMS

Barrett's esophagus (BE) - associated neoplasia can be treated endoscopically, but accurate assessment before intervention is challenging. This study aimed to investigate the role of confocal laser endomicroscopy (CLE) as an adjunct in the endoscopic treatment of BE-associated neoplasia by assessing lateral tumor and subsquamous tumor (SST) extension.

PATIENTS AND METHODS

In the context of a prospective, single-arm pilot clinical trial, patients referred for endoscopic resection of BE-associated neoplasia (high grade dysplasia and esophageal adenocarcinoma) underwent high definition, white light endoscopy with narrow-band imaging (NBI). Then, CLE mapping of suspected neoplastic lesions was performed by another endoscopist, partially blinded to the previous findings, before the patients underwent endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD), depending on lesion size and anticipated histology.

RESULTS

In 7 of 38 patients (18 %), CLE revealed additional neoplastic tissue compared with prior white light endoscopy and NBI: 2 concomitant lesions, 2 cases of lateral tumor extension within the Barrett's epithelium, and 3 cases of previously undetected SST extension. Overall, en bloc resection (tumor-free lateral margin) was achieved in 28 of 34 neoplastic lesions (82 %), and complete resection (tumor-free lateral and basal margins) in 21 of 34 neoplastic lesions (62 %).

CONCLUSIONS

CLE-assisted endoscopic resection of BE-associated neoplasia was safe and effective in this study, as proved by a high additional diagnostic yield of CLE (including visualization of occult SST extension) and a favorable rate of en bloc resection. The clinical value of CLE for assisting endoscopic therapy of BE-associated neoplasia deserves further evaluation in randomized controlled trials.