Clinical Trial to Evaluate the Efficacy and Safety of SUBMO® as a Submucosal Injection Agent in Endoscopic Resection of Superficial Gastrointestinal Lesions.

Inclusion Criteria: * Subjects \>18 years old. * Presence of a colorectal lesion larger than 10 mm, confirmed through colonoscopy. * The lesion must be considered technically resectable using either Endoscopic Mucosal Resection (RME) or Endoscopic Submucosal Dissection (DSE). * The participant must be willing and able to comply with all required study visits and procedures, according to the protocol. * The participant must understand, sign, and date the written informed consent form before undergoing any study-specific procedures. Exclusion Criteria: * Severe comorbidities according to clinical judgment, including patients classified as ASA IV or ASA V, except those ASA IV cases explicitly approved as clinically safe by the center's Anesthesiology Service (using the ASA anesthetic classification). * Patients presenting some coagulopathy that prevents safe endoscopic resection. * Lesions that are suspicious endoscopic invasive cancer. * Any medical condition that, in the investigator's opinion, could compromise patient safety or protocol adherence. * Known allergy or hypersensitivity to any component of the investigational product, including hyaluronic acid, methylene blue, or any excipients. * Contraindications to colonoscopy or to the administration of sedation/anesthesia. * Current participation in another clinical investigation with an investigational product, or participation in any clinical study (with tested or untested products) within the previous 30 days prior to randomization. * Pregnant or breastfeeding women.