The colon and rectum are part of the large intestine. Colorectal cancer occurs when tumors form in the lining of the large intestine. It is common in both men and ...YouAreHere:Home→HealthTopics→ColorectalCancerURLofthispage:https://medlineplus.gov/colorectalcancer.htmlColorectalCancerAlsocalled:Coloncancer,RectalcancerOnthispageBasicsSummaryStartHereDiagnosisandTestsPreventionandRiskFactorsTreatmentsandTherapiesLearnMoreLivingWithRelatedIssuesGeneticsSee,PlayandLearnImagesHealthCheckToolsVideosandTutorialsResearchStatisticsandResearchClinicalTrialsJournalArticlesResourcesReferenceDeskFindanExpertForYouChildrenPatientHandoutsSummaryThecolonandrectumarepartofthelargeintestine.Colorectalcanceroccurswhentumorsformintheliningofthelargeintestine.Itiscommoninbothmenandwomen.Theriskofdevelopingcolorectalcancerrisesafterage50.You'realsomorelikelytogetitifyouhavecolorectalpolyps,afamilyhistoryofcolorectalcancer,ulcerativecolitisorCrohn'sdisease,eatadiethighinfat,orsmoke.SymptomsofcolorectalcancerincludeDiarrheaorconstipationAfeelingthatyourboweldoesnotemptycompletelyBlood(eitherbrightredorverydark)inyourstoolStoolsthatarenarrowerthanusualFrequentgaspainsorcramps,orfeelingfullorbloatedWeightlosswithnoknownreasonFatigueNauseaorvomitingBecauseyoumaynothavesymptomsatfirst,it'simportanttohavescreeningtests.Everyoneover50shouldgetscreened.Testsincludecolonoscopyandtestsforbloodinthestool.Treatmentsforcolorectalcancerincludesurgery,chemotherapy,radiation,oracombination.Surgerycanusuallycureitwhenitisfoundearly.NIH:NationalCancerInstituteStartHereGeneralInformationaboutColonCancer(NationalCancerInstitute)AlsoinSpanishGeneralInformationaboutRectalCancer(NationalCancerInstitute)AlsoinSpanishGetTestedforColorectalCancer(OfficeofDiseasePreventionandHealthPromotion)WhatIsColorectalCancer?(AmericanCancerSociety)AlsoinSpanishDiagnosisandTestsAbdominalexploration-slideshow(MedicalEncyclopedia)AlsoinSpanishAnoscopy(NationalLibraryofMedicine)AlsoinSpanishBetterCheckYourBowels:ScreeningforColo