Gastrointestinal cancers compromise one of the most rising incidence cancers worldwide. Owing to their late clinical presentation, the prognosis of these malignancies has a very grave outcome. From this piece of information came the thought of introducing a mass screening programs to identify true high risk population for the development of such cancers and those with precancerous lesions, and then to enroll them into an intensified surveillance protocol with well defined separation intervals to monitor any neoplastic transformation in these population. Endoscopic surveillance modalities have been always regarded as the golden surveillance measures for these patients, and the newer endoscopic modalities such as chromoendoscopy, autufluoresecence endoscopy, confocal endomicroscopy, and narrow band imaging, have largely replaced conventional esophagogarstroduodenoscopy (EGD), and colonoscopy. But since most of these measures are invasive, coasty, and may not be applicable, another non invasive screening and surveillance protocol has emerged which relies mainly upon serum biomarkers for different gastrointestinal cancers or genetic succeptibility tests. However , neither of these tools have proven the same or even the near efficacy and accuracy of endoscopic measures, and that lead to the invention of anon invasive endoscopic modalities such as optical coherence tomography (OCT), FICE system, and virtual colonoscopy