Brief Summary: This is a retrospective and prospective multicenter registry to collect long-term data (1 year) on patients who have or will undergo Endoscopic resection such as EMR, ESD, EFTR, STER, etc. within the gastrointestinal tract for endoscopic treatment of early gastrointestinal neoplasms involving the resection of the superficial layers, mucosa and submucosa, of the tract wall. Subjects will be consented for medical chart review. The purpose of this retrospective and prospective registry is to assess long term data on efficacy, safety and clinical outcome of Endoscopic Resection within the gastrointestinal tract (1 year). The registry will evaluate efficacy, technical feasibility, clinical outcome, safety profile and overall clinical management through medical chart review. The procedures the investigators are evaluating are all clinically indicated and will not be prescribed to someone to participate in this registry study.

Detailed Description: Endoscopic resection can be an appropriate approach in early neoplasms, challenging adenomas or sub-epithelial lesions. Endoscopic resection can be considered as a less invasive approach than surgery. Moreover, endoscopic resection can be available to patients who are ineligible for surgery or who have refused more aggressive surgical intervention. The study investigators would collect data on a large sample size of subjects undergoing various endoscopic resection procedures such as EMR (Endoscopic Mucosal Resection), ESD (Endoscopic submucosal dissection), STER (Submucosal tunneling endoscopic resection, and EFTR (Endoscopic full-thickness resection). Clinical metrics will be recorded including procedure times, length of follow-up, specific tumor characteristics, resection method, pathology results, procedural complications, additional therapy required, and disease-free survival time. Currently, there is limited multi-center data on endoscopic resection outcomes in western populations. Evaluation of these measurement would help the investigators compare them to conventional treatment modalities within current tertiary facilities; and consequently help the investigators identify appropriate treatment techniques and improve clinical management of patients at WCMC-NYPH. The purpose of this retrospective and prospective registry is to assess long term data on efficacy, safety and clinical outcome of Endoscopic Resection within the gastrointestinal tract (1 year).