Neoplastic lesions of the gastrointestinal tract have a large prevalence worldwide and in Romania. Their therapy is tailored to their TNM stage, which can be estimated using non invasive or minimally invasive imaging studies. Precursor lesions and superficial carcinomas are amenable to endoscopic therapy, providing that their endoscopic and/or endoscopic ultrasound aspect suggest a maximal extension to the submucosal layer. Polypectomy, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are ablative techniques used for their curative intent treatment. Large superficial carcinomas are to be removed by ESD as "en bloc" resection is essential to post procedure histological appraisal of the curative oncology nature of their resection. ESD complications rates and duration are nowadays reduced with the aid of "water-jet" technology, by combining submucosal fluid jet injection and electro-resection in a single knife.