The rate of missing neoplasia of the GI tract has been demonstrated, and one of the reasons is the amount of flat lesions that have gone undetected. The Paris endoscopic classification is a unified evaluation of early cancers at all levels of the digestive tract. The presence of flat lesions obliges the endoscopist to apply more precise diagnostic techniques. These new image techniques make the diagnosis of early lesions easier and in consequence, it also simplifies their treatment.