Response to ‘Rectal versus colonic submucosal cancer rates and procedural outcomes in large non-pedunculated polyps: French ESD registry data’

We read with great interest the study by Van der Voort et al,1 which compared rectal versus colonic submucosal cancer rates in large non-pedunculated colorectal polyps (LNPCPs) using the French endoscopic submucosal dissection (ESD) registry. We commend this group for their immense contributions to advancing ESD research and practice. Their collaborative efforts have generated one of the most valuable data sets internationally, significantly shaping understanding of procedural outcomes and oncological risk in Western practice. Although the data set is undeniably impressive, we wish to draw attention to a key methodological concern: the inherent referral stream bias and resulting limited external validity of the conclusions.