Endoscopic Mucosal Resection Versus Endoscopic Submucosal Dissection for Colorectal Laterally Spreading Lesions.

This study compares two methods of removing large polyps or precancerous lesions from the colon using a colonoscope: EMR (endoscopic mucosal resection), which uses a snare to remove tissue, versus ESD (endoscopic submucosal dissection), which cuts out tissue in a single piece. The goal is to find out which approach is safer and more effective for specific types of lesions. **You may be eligible if...** - You are 18 or older - You have a specific type of large colon lesion (at least 20–30 mm depending on the type) that has not been previously treated - You have had or will have a full colonoscopy to check the rest of the colon - You are able to complete questionnaires in Spanish or English **You may NOT be eligible if...** - You have a health condition that prevents you from having a colonoscopy or anesthesia - You cannot safely stop blood thinners before the procedure - Your lesion has already been treated or injected previously - Your lesion shows signs of deep invasion (suggesting cancer) - You have more than one qualifying lesion Talk to your doctor to see if this trial is right for you.