♦The main intent of ESD is not only to achieve en bloc resection but to obtain acceptable R0 resection too ( resection without any residuals on microscopy). ♦Any residual pathology ( R1 resection) can lead to recurrence. ♦However, cautery artifact at the margin of the resection could look like R1. ♦In a recent study from @bcm_gihep, @FaresAyoubMD and @MaiAhmedKhalaf reviewed 614 ESD cases. They found that from 37 R1 lesions after ESD for colonic adenomas, none had recurrence on follow up. ♦Recurrence was mainly seen in patients with esophageal squamous cell carcinoma , adenocarcinoma, or with deep margin positivity. ♦ Few comments about ESD techniques inspired from this study results for ESD enthuiasts : 👉Colonic mucosa is very thin and it can easily get cauterized with minimal coagulation. Having adequate normal mucosa around the lesion prevent cautery artifact and mislabeling resection as R1. This can also facilitate traction assisted ESD ( by grasping on sufficient normal mucosa on the oral side of the lesion). 👉In my experience, right and left borders of colonic lesions tend to have less normal tissue around it after resection and it is the cause of mislabeling as R1( rather than oral or anal margins). Make sure to include enough normal tissue on both lateral side of the resections, marking can help with that. 👉Treat R1 after any esophageal or gastric resection seriously and bring the patient for an additional salvage ESD of any residual tumor in 8 to 10 weeks from first resection. ovidsp.ovid.com/ovidweb.cgi?…