Qidong(Jiangsu,China)hasbeenofinteresttocancerepidemiologistsandbiologistsbecause,untilrecently,itwasanendemicareaforlivercancer,havingamongstthehighestincidenceratesintheworld.TheestablishmentoftheQidongCancerRegistrytogetherwiththeQidongLiverCancerInstitutein1972haschartedthepatternsoflivercancerincidenceandmortalityinastablepopulationthroughoutaperiodofenormouseconomic,social,andenvironmentalchangesaswellasofimprovementsinhealthcaredelivery.UpdatedincidencetrendsinQidongaredescribed.Notably,theChinaage-standardizedincidencerateforlivercancerhasdroppedbyover50%inthepastseveraldecades.MolecularepidemiologicandgenomicdeepsequencingstudieshaveaffirmedthatinfectionwithhepatitisBvirusaswellasdietaryexposuretoaflatoxinsthroughcontaminationofdietarystaplessuchascorn,andtomicrocystins–blue-greenalgaltoxinsfoundinditchandpondwater–werelikelyimportantetiologicfactorsthataccountforthehighincidenceoflivercancerinthisregion.PublichealthinitiativestofacilitateuniversalvaccinationofnewbornsagainstHBVandtoimprovedrinkingwatersourcesinthisruralarea,aswellaseconomicandsocialmandatesserendipitouslyfacilitatingdietarypersity,haveledtoprecipitousdeclinesinexposurestotheseetiologicfactors,concomitantlydrivingsubstantivedeclinesinthelivercancerincidenceseennowinQidong.Inthisregard,Qidongservesasatemplatefortheglobalimpactthatapackageofinterventionstrategiesmayexertoncancerburden.
