CK7+ / CK20+ in carcinomas of bile duct (extrahepatic / gallbladder, often, Pathol Res Pract 2003;199:65), lung-mucinous bronchioloalveolar ...AuthorsBlogBoardReviewCommentContactUsNewslettersStatisticsTestimonialsSeeElsevier'snewvideoabouttheirClinicReviewArticlesonourhomepageorclickhere.JobsFellowshipsConferences/WebinarsBooksCMECasesAdvertiseGrantsMedicalNewsLibrariesRocheCompanionDiagnosticLibraryRocheNTRKIHCDiagnosticLibraryCOVID-19LibraryPandemicreliefmusicawardHome>Stains&molecularmarkers>Cytokeratin20(CK20,K20)Stains&molecularmarkersCytokeratin20(CK20,K20)Author: NatPernick,M.D.TopicCompleted:1July2013Minorchanges:19October2020Copyright:2003-2021,PathologyOutlines.com,Inc.PubMedSearch:CK20[title]Pageviewsin2020:17,186Pageviewsin2021todate:6,192TableofContentsDefinition/general|Usesbypathologists|Microscopic(histologic)images|Positivestaining-normal|Positivestaining-notmalignant|Positivestaining-malignant|NegativestainingCitethispage:HamiltonK,PernickN.Cytokeratin20(CK20,K20).PathologyOutlines.comwebsite.https://www.pathologyoutlines.com/topic/stainsck20.html.AccessedApril21st,2021.Definition/generalEpithelialmarker(MW46kDa)withrestrictedexpressioncomparedtoCK7(OMIM#608218)UsesbypathologistsGeneralpatterns(specificityvaries)CK7+/CK20+incarcinomasofbileduct(extrahepatic/gallbladder,often,PatholResPract2003;199:65),lung-mucinousbronchioloalveolar(AmJClinPathol2004;122:421),pancreas(Cancer2006;106:693,butseeArchPatholLabMed2000;124:1196)Urothelium(often,ArchPatholLabMed2001;125:921,HumPathol2002;33:1136)Alsoprimarymucinoustumorsofovary(74%),upperGItract(78%)andendocervix(88%,AmJSurgPathol2006;30:1130)CK7+/CK20-incarcinomasofbileduct(intrahepatic,PatholResPract2003;199:65),breast(AnnDiagnPathol1999;3:350),endocervicalandendometrialadenocarcinoma(PatholResPract2003;199:65),esophagus(distal,AmJSurgPathol2002;26:1213),lung(notmucinousbronchioloalveolar,BMCCancer2006;6:31),salivarygland(PatholInt2005;55:386),thyroid(ApplImmunohistochemMolMorphol2000;8:189)Alsomesothe