N2 Disease in T1 NonSmall Cell Lung Cancer.docx

N2 Disease in T1 NonSmall Cell Lung Cancer.docx

《N2 Disease in T1 NonSmall Cell Lung Cancer.docx》由会员分享，可在线阅读，更多相关《N2 Disease in T1 NonSmall Cell Lung Cancer.docx（10页珍藏版）》请在冰豆网上搜索。

N2DiseaseinT1NonSmallCellLungCancer

N2DiseaseinT1Non-SmallCellLungCancer

SebastianA.Defranchi,MD,StephenD.Cassivi,MD,MS,FrancisC.Nichols,MD,MarkS.Allen,MD,K.RobertShen,MD,ClaudeDeschamps,MD,andDennisA.Wigle,MD,PhD

DivisionofGeneralThoracicSurgery,MayoClinic,Rochester,Minnesota

AddresscorrespondencetoDrWigle,DivisionofGeneralThoracicSurgery,MayoClinic,200FirstStSW,Rochester,MN55905;Email:

wigle.dennis@mayo.edu

Thepublisher'sfinaleditedversionofthisarticleisavailableatAnnThoracSurg

Seecommentary"SonicHedgehog（SHH）PromotestheDifferentiationofMouseCochlearNeuralProgenitorsviatheMath1–Brn3.1Signalingpathwayinvitro"inJNeurosciRes,volume88on page 928.

∙ OtherSections▼

oAbstract

oMaterialandMethods

oResults

oComment

oReferences

Abstract

Background

Theoptimalmanagementstrategyformediastinalstaginginearly-stagenon-smallcelllungcancer（NSCLC）isnotclearlydefined.Thetrueprevalenceofmediastinallymphnodemetastases（N2disease）inresectedpathologicT1（pT1）NSCLCmustbeknowntodefinetheroleofinvasivemediastinalstaginginthesepatients.

Methods

DataofpatientswithpT1lesionsresectedatMayoClinicbetween1998and2006wereretrospectivelyreviewed.PatientswithN2diseasewereidentifiedfrompathologyandoperativereports.Werevieweddemographics,radiologicdata,andsurgicalproceduresforthosewithpathologicT1N2NSCLC.

Results

Weidentified968casesofpT1lesions,59withpN2disease（6.1%）.ForthosewithT1N2disease,theprimarylunglesionwasperipheralin18（31%）andcentralin41（69%）.Ofthese,36hadnegativenon-invasivemediastinalstaging（3.7%）andwereincidentallydiscovered.Themostfrequentlyaffectedlymphnodestationwas7in22patients（37%）,followedby5,6in18（31%）.Mediastinoscopyfoundpositivelymphnodesin3of16patients（19%）inwhichitwasperformed.Overall5-yearsurvivalforpT1N2incidentallydiscoveredduringmediastinallymphnodedissectionatthetimeoflungresectionwas46%（95%confidenceinterval,31%to68%）.

Conclusions

TruepT1NSCLCharborsarelativelylowrateofN2disease.TherateofoccultN2diseasenotobservedonnoninvasivepreoperativemediastinalstagingisevenlower.ForpatientswithT1NSCLCandnegativemediastinalimaging,routinemediastinoscopyresultsinalowyieldofoccultN2diseasediscovery.

∙ OtherSections▼

oAbstract

oMaterialandMethods

oResults

oComment

oReferences

CurrenttreatmentalgorithmsforlocallyadvancedstageIIInon-smallcelllungcancer（NSCLC）typicallyinvolveneoadjuvantordefinitivechemoradiationtherapy.SurgicalresectionisnotnormallyusedasinitialtreatmentinmostNorthAmericancenters.Asaconsequence,mucheffortisdirectedtowardtheassessmentofmediastinallymphnodesformetastaticdiseasebeforeanyplannedsurgicalresection.

Computedtomography（CT）hasasensitivityof50%to76%andspecificityof55%to86%forpredictingmeta-staticinvolvementofmediastinallymphnodeswhentheyexceed1cmintheshortaxis[1–3].Positronemissiontomography（PET）hasemergedasausefultooltoevaluatethemediastinum,withasensitivityof83%to91%andspecificityof70%to91%forlymphnodemetastases[3,4].Despitethesenumbers,pathologictissueconfirmationisdesirabletoprovethatalesionisindeedmalignantandnotexcludepotentiallyresectabletumorsfromsurgicaltreatmentandpotentialcure.

SomehavesuggestedthattheincidenceoflymphnodemetastasesinpatientswithclinicalT1NSCLCandnegativenoninvasivemediastinalstagingmightbelowenoughtoprecluderoutineinvasivestagingbymediastinoscopy[5,6].ReportsvaryaboutthetruerateofoccultN2diseaseinNSCLCpatientswithnegativenoninvasivestaging,particularlyforpatientswithT1lesions.TheobjectiveofthisstudywastodescribetheincidenceofN2diseasein968consecutivecasesofresectedpathologicT1（pT1）NSCLCandmakeinferencesabouttheutilityofinvasivemediastinalstaginginthissubgroupofpatients.

∙ OtherSections▼

oAbstract

oMaterialandMethods

oResults

oComment

oReferences

MaterialandMethods

ThisstudywasapprovedbytheMayoClinicCollegeofMedicine’sInstitutionalReviewBoard.

Patients

WereviewedourprospectivedatabaseforallpatientsthatunderwentresectionforpT1NSCLCbetween1998and2006atMayoClinic,Rochester,Minnesota.Allpathologyreportsforthesepatientswerereviewed.Weidentified968casesinvolvingsurgicalproceduresinpatientswithpT1NSCLC.Ofthese,59（6.1%）werefoundtohavepathologicN2（pN2）disease.Preoperativedatawerereviewedforthisgroup,includingage,gender,pulmonaryfunctiontests,localizationoftheprimarytumor,presenceofadenopathyonCTscan,andsizeandmetabolicactivityonPETscaninthosepatientsforwhichitwasperformed.Thesurgicalandpathologyreportswerereviewedforthemediastinallymphnodesstationsthatweresampledandwhichofthemcontainedmetastases.

LesionswerestagedaccordingtothestagingsystemandmediastinallymphnodemapdescribedbyMountain[7,8].Thesizeofthelesionwasdeterminedfromthegreatestdimensionmeasuredinthepathologylaboratory.

ImagingData

AlltheavailableCTscanswerereviewed.PeripherallungnodulesweredefinedonCTscanastumorswiththecenterlocatedintheouterthirdofthelungineitherthesagittalorcoronalplane.IfCTimageswerenotavailable,aperipherallesionwasdefinedaccordingtoitsrelationtothepleuralsurfaceasdescribedinthepathologyreport.MediastinallymphnodeswereconsideredtobepositivebyCTscancriteriawhentheirshortaxiswas10mmormoreinsize.InpatientsinwhomPETscanswereperformed,reportswerereviewedandconsideredpositiveifthedescribedmetabolicactivityinthemediastinumexceeded1.5-foldoverbackgroundlevels.

Mediastinoscopy

Cervicalmediastinoscopywasperformedinthestandardfashionandselectively,determinedbythepresenceofsignificantlymphnodesinthemediastinumobservedonCTscan,byincreasedmetabolicactivityonPET,orbysurgeonpreference.Afterintroductionofthemediastinoscope,biopsyspecimensfromstation4R,7,and4Lweretypicallyobtained.Biopsyspecimenswerealsoobtainedfromotherstationswhenlymphnodeswereencounteredorspecificallysoughtout.

MediastinalLymphNodeDissection

Mediastinallymphnodedissection（MLND）wasperformedaspartoflungresections.Forright-sidedprocedures,thelymphnodestations2R,4R,7,and9wereroutinelydissected;forleft-sidedprocedures,thenodesfromstations5,6,7,and9wereincluded.Onbothsides,otherlymphnodestationsencounteredorspecificallysoughtoutatthetimeofthelungresectionwerealsoremoved.

Statistics

Descriptivestatisticsarereportedasmedianandrangeforcontinuousvariablesandasfrequencyandpercentagefordiscretevariables,basedontumorstatus（N2vsN0/N1）.AssociationswithtumorstatusweremadeusingtheWilcoxonranksumtestforcontinuousvariablesandχ2testorFisherexacttestasappropriatefordiscretevariables.Theα-levelwassetat0.05forstatisticalsignificance.

∙ OtherSections▼

oAbstract

oMaterialandMethods

oResults

oComment

oReferences

Results

Between1998and2006,968patientsunderwentlungresectionforpT1NSCLC.Ofthese,59（6.1%）werefoundtohaveN2disease（32men,27women）.Peripherallesionswerefoundin18patientsandcentrallesionsin41（69%）.Lungtumorswereontherightsidein25（43%）andontheleftsidein34（57%）.Lobectomybyopenthoracotomywasperformedin54（92%）,andwedgeresectionin5（8%）.PatientcharacteristicsarelistedinTable1.

Table1

CharacteristicsforpT1N2Patients

ImagingData

CTcriteriawereusedtoestablishmediastinaladenopathyin17of59patients（29%）.ThemostfrequentlymphnodestationfoundtobepositivebyCTscancriteriawasstation4Rin10patients（17%）,followedbystation7in6（10%）.In8patients（14%）,CTshowedadenopathyinN1-levellymphnodes.

PETscanwasdonein27patients（46%）,resultingin18（31%）withnegativemediastinallymphnodesand9（15%）withpositivenodes.In3patientstheCTandPETscanswerebothpositiveforthesamelymphnodestations.In2patientsthisinvolvedstation4Rwithmetastasesfoundattimeofoperationafteranegativemediastinoscopy.Theremainingcaseinvolveda5,6lymphnodestation,withmetastasisconfirmedduringleft-sidedlungresection.

SurgicalData

Mediastinoscopywasperformedin16of59T1N2patients（27%）,andin11of23withpreoperativefeaturesofN2disease.In3of16patients（19%）,mediastinoscopyfoundlymphnodemetastasesinthemediastinum,and2subsequentlyreceivedneoadjuvantchemoradiationtherapy,followedbypulmonaryresection.Thethirdpatienthadcomplicationswithbleedingduringthemediastinoscopyprocedure,forwhichathoracotomywasperformedalongwiththelungresection.Intheremaining13patients（81%）,mediastinoscopydidnotrevealthepresenceoflymphnodemetastases,despitethediscoveryofN2diseaseduringMLNDatthetimeoflungresection.Overall,mediastinoscopywasabletoidentifymediastinallymphnodeinvolvementinonly3of9patients（33%）wherethepositivelymphnodeswerewithinthefieldaccessiblebycervicalmediastinoscopy.

InN2-positivecases,themediansizeoftheT1pulmonarylesionswas2cm（range,0.9to3cm）.Only1lesionwaslessthan1cm,37lesionsmeasuredbetween1and2cm,and21lesionsweremorethan2cminthegreatestdimension.ThelocationoftheprimarylesionforspecificN2-positivestationsisdescribedinTable2.

Table2

Fr