SubdivisionofMcategoryfornasopharyngealcarcinomawithsynchronousmetastasis:timetoexpandtheMcategorizationsystem

摘要： Introduction:Thecurrentmetastaticcategory(M)ofnasopharyngealcarcinoma(NPC)isacatch-allclassification,coveringaheterogeneousgroupoftumorsrangingfrompotentiallycurabletoincurable.TheaimofthisstudywastodesignanMcategorizationsystemthatcouldbeappliedinplanningthetreatmentofNPCwithsynchronousmetastasis.Methods:Atotalof505NPCpatientsdiagnosedwithsynchronousmetastasisatSunYat-senUniversityCancerCenterbetween2000and2009wereinvolved.Theassociationsofclinicalvariables,metastaticfeatures,andaproposedMcategorizationsystemwithoverallsurvival(OS)weredeterminedbyusingCoxregressionmodel.Results:MultivariateanalysisshowedthatUnionforInternationalCancerControl(UICC)Ncategory(N1-3/N0),numberofmetastaticlesions(multiple/single),liverinvolvement(yes/no),radiotherapytoprimarytumor(yes/no),andcyclesofchemotherapy(>4/<4)wereindependentprognosticfactorsforOS.Wedefinedthefollowingsubcategoriesbasedonliverinvolvementandthenumberofmetastaticlesions:Mia,singlelesionconfinedtoanisolatedorganorlocationexcepttheliver;Mlb,singlelesionintheliverand/ormultiplelesionsinanyorgansorlocationsexcepttheliver;andM1c,multiplelesionsintheliver.Ofthe505cases,74(14.7%)wereclassifiedasMia,296(58.6%)asM1b,134(26.5%)asM1c,and1wasnotspecified.ThethreeMlsubcategoriesshowedsignificantdifferenceinOS[Mlbvs.Mia,hazardratio(HR)=1.69,95%confidenceinterval(CI)=1.16-2.48,P=0.007;Mlcvs.Mla,HR=2.64,95%CI=1.75-3.98,P<0.001],Conclusions:WedevelopedanMcategorizationsystembasedontheindependentfactorsrelatedtotheprognosisofpatientswithmetastaticNPC.ThissystemmaybehelpfultofurtheroptimizeindividualizedcareforNPCpatients. ... （共9頁）