RectumSigmoid NeoplasmsColon, SigmoidSigmoid DiseasesRectal DiseasesRectal NeoplasmsColon, DescendingRectal ProlapseRectal FistulaMegacolonColonCecal NeoplasmsColonic PolypsColonic DiseasesColonoscopyConstipationSigmoidoscopyGastrointestinal TransitPolypsManometryEndometriosisHirschsprung DiseaseGastrointestinal MotilityAdenomaDigestive System Surgical ProceduresColonic Diseases, FunctionalColorectal NeoplasmsColonic NeoplasmsAdenocarcinomaIrritable Bowel SyndromeColitis, UlcerativeIntestinal MucosaAnal CanalLaparoscopyFoodProctoscopyProspective StudiesElectromyographyRetrospective StudiesIntestinal PolypsForecastingTime FactorsCase-Control StudiesTreatment OutcomeProctitisColostomyAdministration, RectalPrevalenceDefecationRadiotherapy Planning, Computer-AssistedColectomyIntestine, LargeSurgical StaplersAdenoma, VillousEnemaAnus, ImperforatePerineumGastrointestinal HemorrhageDigestive System NeoplasmsBrachytherapyRadiotherapy DosageOrgans at RiskColon, TransversePelvisRectovaginal FistulaIleostomyGastrointestinal Neoplasms