Differentiation is the grade of the cancer, which is based on how abnormal the cells look under the microscope. Cancers that are higher grade or poorly differentiated tend to grow and spread more quickly. Colon cancer is usually divided into 3 grades: Well differentiated (low grade)Whatpatientsandcaregiversneedtoknowabout cancer,coronavirus,andCOVID-19.CloseCriticalAlertBannerSearchVerenespañol|Downloadthistopic[PDF]Treatment&SupportUnderstandingYourDiagnosisExamsandTestsforCancerUnderstandingYourPathologyReportColonPathologyUnderstandingYourPathologyReport:InvasiveAdenocarcinomaoftheColonWhenyourcolonwasbiopsied,thesamplestakenwerestudiedunderthemicroscopebyaspecializeddoctorwithmanyyearsoftrainingcalledapathologist.Thepathologistsendsyourdoctorareportthatgivesadiagnosisforeachsampletaken.Thisreporthelpsmanageyourcare.Thequestionsandanswersthatfollowaremeanttohelpyouunderstandthemedicallanguageusedinthepathologyreportyoureceivedforyourbiopsy.Theydonotcoveralloftheinformationthatwouldbeinapathologyreportthatwouldresultfromhavingpartofyourcolonremoved(resected)totreatcoloncancer.Whatifmyreportmentionsthececum,ascendingcolon,transversecolon,descendingcolon,sigmoidcolon,orrectum?Theseareallpartsofthelargeintestine.Thececumisthebeginningofthecolon,wherethesmallintestineemptiesintothelargeintestine.Theascendingcolon,transversecolon,descendingcolon,andsigmoidcolonareotherpartsofthecolonafterthececum.Thecolonendsattherectum,wherewasteisstoreduntilitexitsthroughtheanus.Whatisadenocarcinomaofthecolon(orrectum)?Adenocarcinomaisatypeofcancerthatstartsinthecellsthatformglandsmakingmucustolubricatetheinsideofthecolonandrectum.Thisisthemostcommontypeofcolonandrectumcancer.Whatdothewordsinvasiveorinfiltratingmean?Ascoloncancergrowsandspreadsbeyondtheinnerliningofthecolon(mucosa),itiscalledinvasive(orinfiltrating)adenocarcinoma.Cancersthatareinvasivearecalledtruecancersbecausetheycanspreadtootherplacesinthebody.Doesthismeanthatthetumorhasinvadeddeeplyandisassociatedwithapoorprognos