Clinicaltreatmentconsiderationsintheintensity-modulatedradiotherapyeraforpatientswithNO-categorynasopharyngealcarcinomaandenlargednecklymphnodes

摘要： Background:Nasopharyngealcarcinoma(NPC)showsahighproportionoflymphnodemetastasis,andtreatmentguidelineshavebeendevelopedforpositivenodes.However,noirradiationguidelineshavebeenproposedforpatientswithenlargednecklymphnodes(ENLNs)thatdonotmeettheradiologicalcriteriaof10mmindiameterforpositivelymphnodes.ThisstudyaimedtodeterminetheprognosticvalueandradiationdoseforENLNsinNO-categoryNPCpatientstreatedwithintensity-modulatedradiotherapy(IMRT).Methods:Wereviewedthemedicaldataof251patientswithnon-metastatic,NO-categoryNPCtreatedwithIMRT.Receiveroperatingcharacteristiccurveswereusedtocalculatethecut-offvalueoftheENLNdiameterforthepredictionofdiseasefailure.Thebiologicalequivalentdose(BED)forENLNswascalculated.PatientsurvivalwascomparedbetweenthesmallandlargeENLNgroups.IndependentprognosticfactorswereidentifiedusingtheCoxproportionalhazardsmodel.Results:Theestimated4-yearregionalrelapse-freesurvivalratewashigherinpatientswithENLNs≥5.5mmthaninthosewithENLNs<5.5mm(100%vs.98.8%,P=0.049),whereasdisease-free,overall,anddistantmetastasis-freesurvivalratesweresimilarbetweenthetwogroups.Afteradjustingforvariousfactors,ENLNdiameterwasnotidentifiedasanindependentprognosticfactor(P>0.05forallsurvivalrates).Inthesubgroupanalysis,patientsreceivingBED≥72GyhadasimilarprognosisaspatientsreceivingBED<72GyinboththesmallandlargeENLNgroups.ThemultivariateanalysisalsoconfirmedthatBED≥72GywasnotassociatedwithsignificantlyimprovedprognosisinpatientswithNO-categoryNPC.Conclusions:ABEDof72GytoENLNsisconsiderablysufficienttoprovideaclinicalbenefittopatientswithNO-categoryNPC.Prospectivestudiesarewarrantedtovalidatethefindingsinthepresentstudy. ... （共9頁(yè)）