A Prospective Investigation of the ColubrisMX ELS System

INCLUSION CRITERIA All of the following criteria must be present to be eligible for the study: 1. Aged 18-75 years 2. BMI ≤ 35 kg/m2 3. Patient agrees to participate in the study by giving signed informed consent 4. Benign lesions of the rectum, such as adenoma, submucosal nodule, or polyp 5. Mucosal neoplasm 6. Eligible to undergo standard endoscopic submucosal dissection. 7. Patient reviewed and approved by Local Oncology Committee to undergo robotic procedure. EXCLUSION CRITERIA Patients will be excluded from the study if any of the following criteria are present: Preoperative 1. Anatomy unsuitable for endoscopic visualization or endoluminal surgery 2. Extensive previous surgery in the lower GI tract 3. Prior radiation treatment for colorectal cancer 4. Patient with distant metastases 5. Untreated active infection 6. Vulnerable population (e.g., prisoners, mentally disabled) 7. Severe concomitant illness (i.e., cancer) that drastically shortens life expectancy or increases risk of therapeutic interventions 8. Breastfeeding or pregnant, or intend to become pregnant during the course of the study 9. Currently enrolled in or discontinued within the last 30 days from a clinical trial of an investigational drug or device, or concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study 10. In the opinion of the Investigator, the patient is unable to comply with the requirements of the study protocol or is unsuitable for the study for any reason. 11. Patients with immunosuppression drugs (chemotherapy) due to an increase potential infection and poor healing 12. Patients with a high cardiac or pulmonary risk (these patients require clearance from a cardiologist and pulmonologist) 13. Preoperative blood thinner i.e., coumadin or heparin. 14. Obstructing rectal cancer 15. History of inflammatory bowel disease Intraoperative 1. Existing stricture or anatomical blockage in lower GI tract preventing overtube from reaching desired position. 2. Disease is more extensive and not amenable to standard ESD 3. Inadequate bowel prep 4. Complex anatomical findings not feasible for endoscopic approach