LocalExcisionofRectalDanielOwenYoungAnjaliSKumarMDMPHTheidealsurg - PDF document

LocalExcisionofRectalDanielOwenYoung,,AnjaliS.Kumar,MD,MPHTheidealsurgicaltreatmentforrectalcancerwouldhavenegligiblemorbidity,andwouldbecurativewhilemaintainingintestinalcontinuityandexcellentfunction.Inmostcases,thisisanunrealizedstandard.Intermsofoncologicoutcome,totalmes-orectalexcision(TME)providesthebestlong-termprognosisforrectalcancer,with Disclosures:Theauthorshavenothingtodisclose. RectalcancerLocalexcision wounds,functionaldisorders,anastomoticleaks,strictures,andperioperativeMoreover,the5-yearlocalrecurrenceratesforradicalsurgery,evenincasesofearly-stagerectalcancers,stillrangefrom2%to8%.Therefore,physicianshaveoftenusedless-invasivetechniqueswhenpossiblethatcouldmitigatethemorbidityofrectalresectionwhileprovidingthepatientwithacceptableoncologicresults,partic-ularlyforearly-stagerectalcancer.Localexcision(LE)ofrectalcancerinvolvesremovalofthetumoritselfwithoutproc-tectomy.InterestinLEforearlydistalrectalcancersbeganinearnestafterMorsonandpublishedtheirexperienceatSt.Mark’sHospitalinLondonin1977demonstratingalowrateoflocalrecurrenceafterexcisionwithnegativemargins.ThissuggestedthatearlyrectalcancercouldbedefinitivelytreatedwithLE,therebysparingpatientsmanyofthemorbiditiesofradicalsurgery.AsenthusiasmforLEhasgrown,sohasitsuseintheUnitedStatesforearly-stagerectalcancer.LEinvolvesfull-thicknessresectionofthetumorandamarginofrectum,downtotheperirectalfat,butnotnecessarilyincludinganydraininglymphatics.Severaldifferentapproachestolocalexcisionhavebeenused,includingoldertranssphinc-tericandtranscoccygealtechniques.Currently,themostwidelyusedtechniqueforLEistransanalexcision(TAE).Conventionaltechniquesaresomewhatlimitedduetopoorvisualizationandconfinementtothedistalrectum.Transanalendoscopicmicrosurgery(TEM)andtransanalminimallyinvasivesurgery(TAMIS)aremorerecentadditionstothesurgeon’sarmamentarium,andallowforimprovedvisualizationandaccesstothemoreproximalrectum.PATIENTSELECTIONPremalignantPolypsAdenomatouspolypsoftendevelopwithintherectum,butsizeandmorphologymaypreventthemfrombeingamenabletocompleteendoscopicremoval.Full-thicknessorpartial-thicknessexcisionoftheselesionscanbedonesuccessfullyviaLE,andcanavoidthemorbidityofmajorpelvicsurgeryinapatientwithoutaninvasivecancer.RectalAdenocarcinomaIngeneral,LEshouldbereservedforfavorableT1lesionswithoutirregularorenlargedlymphnodes.PatientsunderconsiderationforLEofrectalcancershouldunde

rgoroutinestaging,includingcomputedtomography(CT)imagingofthechest,abdomen,andpelvisandserumcarcinoembryonicantigen(CEA)level,aswellasdigitalrectalexamination,proctoscopy,anddedicatedrectalimagingwithMRIorendorectalultra-toassessthedepthoflocalinvasion.BecauselymphaticsarenotreliablyremovedwithLE,thegoalistoselectpatientswithearly-stagetumorsthathavealowriskforlymphaticinvolvementatthetimeofoperation.Acombinationofphysicalexaminationfindings,preoperativeimaging,andhistopathologiccharacteristicsaretakenintoaccount(Table1Ondigitalexamination,thetumorshouldbefreelymobile,asfixedtumorsarepredic-tiveofadvanceddisease.9,10Proctoscopicexaminationshoulddeterminetumorsize,extentofrectalcircumferenceinvolvement,anddistancefromtheanalverge.Tumorslargerthan4cmorinvolvingmorethan50%oftherectalcircumferenceareoftenexcludedfromlocalexcisionfortechnicalreasons,althoughlargetumorsstillcanberemovedviaLEwithaselectiveapproach,andcircumferentialornear-circumferentialre-sectionshavebeendescribedinmodels.Conventionallocalexcisionislimitedtodistaltumors(usuallywithin6–8cmoftheanalverge),whereasTEMandTAMIShaveallowedforsuccessfulresectionofmoreproximallesions(8–20cmfromtheanalverge).Young&Kumar HistologicfeaturesoftheendoscopicbiopsyalsoimpacttheappropriatenessforLE.Featuresincludingpoordifferentiationandlymphovascularinvasionpredictunac-ceptablyhighratesoflymphnodemetastasisandlocalrecurrence,andtheselesionsshouldnotbeconsideredforLE.Tumorbuddingorsprouting,inwhichgroupsofafewtumorcellsareseeninvadingaheadofthemainfrontoftumor,isanotherriskfac-torforlymphnodemetastasisandshouldexcludepatientsfromLE.14–16Depthoftumorinvasionintothebowelwall(T-stage)notonlyimpactsthefeasibilityofacompleteresectionwithnegativemargins,butitisalsocorrelatedwiththelikeli-hoodoflymphnodemetastasis.17,18Preoperativeimagingprovidesanessentialbutimperfectestimatefordepthofinvasion.MRIcanbeusedtoassessdepthofrectalwallinvasion,butinselectpatients,transrectalultrasoundmaybetterdiscriminatebe-tweenT1andT2lesions.SomeevidencesuggeststhatfurthersubclassificationofT1lesionsbasedondepthofinvasionofthesubmucosaallowsforevenbetterstratificationofriskforlymphnodemetastasis(LNM).Bydividingthesubmucosallayerintothirds,tumorscanbeclassi-fiedbydepthofinfiltration,astumorswithdeeperinvasioncorrelatewithincreasedriskformetastasis(SM1superficial1/3,3%riskLNM;SM2middle1/3,8%riskLNM;SM3deep1/3,23%riskLNM

).AnypatientwithclinicalevidenceofLNMshouldnotbeconsideredforLE.Trans-rectalultrasoundisusedtoevaluatemesorectallymphnodes,buthaslimitedaccu-racyandreliesmostlyonsize.MRI,althoughalsoimperfect,maybethemostsensitiveandspecificpreoperativetestforlymphnodeinvolvement,asitcanappre-ciateirregularitiesinsubcentimeternodes.OtherindicationsPatientswithmoreadvancedtumorsalsomaybeappropriateforLEiftheircomorbid-itiesprohibitthemfrombeingcandidatesformajorpelvicsurgery.LEalsomaybeusedforthesetumorswhencurativeresectionisnotthegoal,andthefocusisinsteadonpalliation.Therearealsosomepatientswhosimplyrefuseradicalsurgeryforper-sonalreasons.Forexample,ifpatientsareadamantlyagainsthavingapermanentco-lostomy,theydemonstrateunderstanding,andtheyarewillingtoacceptahigherriskofcancerrecurrencetomaintainintestinalcontinuity,itisappropriatetorespecttheirwishesandperformLEdespitethepotentialforaninferioroncologicoutcome.Asalludedtopreviously,LEofrectallesionsalsomaybeconsideredinpatientswithoutadefinitivediagnosisofrectalcancer,suchasincasesofhigh-gradedysplasia,largepolypsnotamenabletoendoscopicresection,orsubmucosaltumors,includingcarcinoidorgastrointestinalstromaltumors. Table1CriteriaforlocalexcisionofrectalcancerAnatomicHistologicStagingcircumferenceofbowelcminsizeMobileandnonfixedWithin8cmoftheanalvergeforconventionallocalexcisionand20cmfortransanalendoscopicmicrosurgeryortransanalminimallyinvasivesurgerysm1orsm2AbsenceoftumorbuddingAbsenceoflymphovascularWelltomoderateNoevidenceofT2diseaseorlymphadenopathyonMRIorendorectalLocalExcisionofRectalCancer SomesurgeonsalsohaveadvocatedforLEforthosewithacompleteclinicalresponsetoneoadjuvantchemotherapyandradiation.TheyuseLEasabiopsytoconfirmordenyapathologiccompleteresponse.Currently,however,thereisnoroleforthisapproachoutsideofaclinicaltrial.ConventionalLEofrectaltumorscanbedoneviatransanal,transcoccygeal,ortrans-sphinctericapproach.Amongthese,thetransanalapproachisthemostcommon;ourtechniqueisdescribedinthefollowingsection.Transcoccygealandtranssphinctericexcisionarereviewedelsewhere.Regardlessoftheapproach,theprinciplesofLEarethesame:full-thicknessresectionofanintacttumorwith1cmmarginofbenigntissuecircumferentially,andtheabsenceoftissuefragmentation.TransanalExcisionInselectingthebowelpreparationfortheseprocedures,thepatient’sdescriptionofhisorherbowelhabitscanbeusedtodetermineifcleansingenemaswillbeadequate,o

rifafullmechanicalbowelpreparationwillbenecessary.Forpatientswithahistoryofconstipationandstraining,amechanicalbowelpreparationcanreducethelikeli-hoodthatapatientwillstrainimmediatelyafterresection.Forthosewithregularbowelhabits,anenemathenightbeforesurgeryandanotheronthemorningoftheresectionisenoughtoallowforpropervisualization.Preoperativeintravenousantibioticsareoftengivenwithin1houroftheprocedure,althoughthereisnoevidencethatthisde-creasestheriskforsurgicalsiteinfectioninanorectalsurgery.Theseproceduresusu-allytakelessthananhourtoperform.Theycanbedonewithacombinationofintravenoussedation(monitoredanesthesiacare)andalocalanesthetic,oralterna-tivelywiththeuseofgeneralanesthesia,withtheapproachesbeingequallyeffective.Apudendalnerveandperianalblockrelaxestheanalsphincterandhastheadditionalbenefitofimprovingpostoperativepaincontrol.Lithotomypositioningisusuallyadequate,evenforanteriortumors.However,itistypicallyeasiertooperatewiththelesionorientedtowardthefloor,andcertainanteriortumorsmaybeaccessedmorereadilyinthepronejackknifeposition.Usingahead-lampmaximizesvisualization.Whenthepatientispositioned,therectumisfurtherirrigatedwithabulbsyringe.Irrigationwithbetadineisunnecessaryandmaystainthespecimen,obscuringthebordersofthelesion.TheauthorstypicallyuseFergusonplasticanoscopes(CSSur-gical,Inc,Slidell,LA)forretraction.Theseanoscopesarereusableandcomeinmyriaddiametersandlengths(Fig.1).Otherretractors,suchastheLoneStar(LoneStarMed-icalProducts,Inc,Stafford,TX),Sawyer,Hill-Fergusonretractors,orParksretractorsarepreferredbyothers.Theanusisgentlydilateduntilgoodvisualizationisobtained.Next,thelesionismarkedbyscoringthemucosacircumferentiallywithelectrocautery.Thispreservestheintended1-cmmargin,asthetissueoftenbecomesdistortedduringtheresection.Cauteryisthenusedtoincisethefullthicknessoftherectumalongthescoredoutlinearoundthelesion.Theneedle-tipcauteryisoftenusedwithacombinationofcutandcoagulationsettings,asthisdistortsandshrinksthebenigntissuelessthanthespatu-latedcauterytiponthecoagulationsettingalone.Theperirectalfatshouldbevisibleinthewoundoncethespecimenisremoved.ForallLEprocedures(TAE,TEM,andTAMIS),thespecimenshouldbepinnedoutandorientedonacorkboardimmediatelyafterremovalwhilefresh(Fig.2).Thispreventsretractionofthebenigntissuemarginonceplacedinformalin.Young&Kumar Wethoroughlyirrigatethewoundbedandtypicallyclosethedefecttransverselywithin

terrupted3-0Vicrylsutures,althoughsmaller,distaldefectscanbeleftopentohealsecondarily.Arigidorflexibleproctoscopethencanbeusedtoassessforrectalpatencyafterclosureofthedefect.Patientsaretypicallydischargedhomefromtherecoveryarea.TransanalEndoscopicMicrosurgeryandTransanalMinimallyInvasiveSurgeryUseofTEMandTAMISinstrumentationhasbecomemoreprevalentinrecentyears,relyingonlaparoscopictechnologytoassistwithlesionremoval.Althoughthetech-niquewasinitiallyaimedatmoreproximaltumors,manysurgeonsusethesetech-niquesfordistaltumorsaswellbecauseoftheimprovedvisualizationandversatility.SelectionofTEMversusTAMISisusuallybasedonsurgeonpreferenceandtherelativeavailabilityofthe2platforms.Ingeneral,the2techniqueshaveverysimilargoalsandcapabilities,althoughTAMISisnewerandlackslong-termdata. Fig.1.Fergusonanoscopesetprovidesvaryinglengthsanddiametersforaccess.Thesoftbevelallowsforthelesiontofallintoviewforresection.(CSSurgical,Inc,Slidell,LA.) Fig.2.Afterexcision,thefull-thicknessspecimenispinnedtoacorkboardandorientedtothepatient’sanatomyandlateralityonthepathologyslipbyusingthenumbersontheboard(ie,4rightproximal,14leftproximal,6rightdistal,16leftdistal).Seenhereisanadenocarcinomaarisinginapolypthatwasincompletelyexcisedbysnarepoly-pectomyforwhichweperformedconventionaltransanalexcision.LocalExcisionofRectalCancer BecausemoreproximaltumorsareapproachedwithTEMandTAMIS,afullme-chanicalandantibioticbowelpreparationisusuallyusedtominimizeintraoperativecontaminationshouldperitonealviolationoccur.Thisalsolessensthebacterialloadofstoolpassingbytheexcisionsiteinthefirstfewpostoperativedays.Itisimperativethatacompletemechanicalpreparationisachieved,asthepropensityofliquidstooltoobscurethevieworseepoutintothewoundbedisalegitimateconcern.TransanalendoscopicmicrosurgeryTEMwasfirstintroducedinGermanyin1984byDrGerhardBuess,andithasslowlygainedmomentumgloballyoverthepast30yearsasmoreoutcomesdatabecameItusesarigid,beveledproctoscopethatis4cmindiameterand12to20cminlength,alaparoscopiccamera,andmodifiedlaparoscopicinstruments.SpecializedequipmentisnecessaryforTEM,includingdisposabletubing,adedicatedmachineforpneumorectum,andequipmenttopositionthepatientandsecuretheproctoscopetothebed.Thecostofthatequipment,alongwithTEM’ssteeplearningcurve,haspreventedthetechniquefrombeingwidespread.Theprocedureworksbestwhenthepatientsarepositionedwiththelesioninadependentorientation,andthebe

veloftheproctoscopeholdsuptheoppositebowelwall(Fig.3).Inthisway,visualizationisoptimized.Wehavefoundthateveninmorbidlyobesepatients,therigidproctoscopeprovidesexcellentretractionforsafeTransanalminimallyinvasivesurgeryTAMISwasintroducedin2009asanalternativetoTEM,offeringsimilarvisibilityandversatilitywithouttheneedforcertainexpensiveandspecializedpiecesofequip-TAMISalsoallowsfordissectioninmultiplequadrants,andsohasfewerlimitationsonpatientpositioning.Itusesaflexibleanddisposablesingle-portlaparo-scopicentrydevicethroughwhichtrocarsareinsertedorarepre-embedded.Pneu-morectumisachievedwitharegularlaparoscopicCOinsufflator,andconventionallaparoscopiccamerasandgraspersareinserted.BecausebellowingandfoggingofthelensismorecommonwithTAMISthanwithTEM,useofinsufflatorsdesignedtoconstantlyrecirculateandwarmthegasescanbehelpful.TechniquesfordissectionaresimilarforTEMandTAMIS;1-cmmarginsarescoredcircumferentiallywithhookelectrocautery.Thefull-thicknessresectioncanthenbeperformedusingelectrocautery,withgreatcaretakento Fig.3.IllustrationofthebeveledendoftheTEMproctoscope,whichholdsuptheoppositewalloftherectum.Thelesionisplacedinthedependentposition;thus,thepatientisplaced)supineforaposteriortumor,or()proneforananteriortumor.Young&Kumar avoidconinginonthespecimen.ForTAMIS,ultrasonicshearscancounteractthepreviouslydescribedsmokeandfog.Someadvocatefordissectingtheproximalmarginfirst,whereasothersworkinthemoretraditionaldistal-to-proximalmanner.Althoughbothtechniquesareeffective,thesurgeonmustremainfocusedandremovethetissueinawaythatminimizeserrorsinorientation.Afterthespecimenhasbeenextractedandproperlyorientedforpa-thology,asuctionirrigationdeviceisusedtowashthewoundbedandensureDefectsintherectalwallcanbeverylargeafterTEMandTAMIS,anditisbesttoachieveawatertightclosure.Suturingistypicallydoneusinglaparoscopicsuturesandneedledrivers,closingthedefectintherectalwalltransversely.Bothrunningandinterruptedtechniquescanbeused,typicallyusinganabsorbablesuture.Iftheperitonealcavitywasenteredduringdissection,eitherintentionallyorunintentionallydependingontheintendeddepthofresection,thistypicallycanberepairedprimarilywithsutureswithoutanysignificantconsequences.Ofnote,laparoscopicsuturinginthisverysmallfieldcanbetechnicallychal-lenging.Toassistinclosure,silverbeadscanbefastenedlikeclipstotheendsofthesuturetoallowknotlessclosure.Anotherapproachistousebarbedsuture,

andevenspecializedsuturingdevicessuchastheEndostitch(TM,Covidien,Mansfield,MA,USA).Onceclosureiscompleted,itiscrucialtoensurethatthelumenofthebowelwasnotcompromised.Adequatetensionplacedontheedgesofthewoundclosurehelpsmitigatethis,asdoesacombinationoflinearandtransverseclosureapproaches.Attheconclusionofthecase,flexibleorrigidproctoscopyisusedtoensurebowelpatencyandtheabsenceofluminalnarrowing.COMPLICATIONSConventionalLocalExcisionOverall,morbidityandcomplicationratesforLEofrectaltumorsaremuchlowerthanforradicalsurgery.Commoncomplicationsincludeurinarytractinfectionandbleeding,aswellasgastrointestinalcomplaints,suchasdiarrhea.Otheruncommoncomplicationsincludewoundinfectionsorabscesses,thromboembolicevents,and,rarely,rectalstricturesorrectovaginalfistulas.TransanalEndoscopicMicrosurgeryandTransanalMinimallyInvasiveSurgeryLikeconventionalLE,TEMandTAMIShavealowrateofcomplications.Themostcommoncomplicationsareurinaryretention,perioperativebleeding,andperito-nealviolation.InTEM,bothurinaryretentionandperitonealviolationareassociatedwithanteriorandlaterallocationsoftheexcisedtumor.Entryintotheperitoneumhasnotbeenshowntohaveanyincreasedmorbidity,andthisriskisfurtherreducediffullmechanicalandantibioticbowelpreparationisusedandpatientsareobservedovernightwith24hoursofintravenousIncreasedratesofintraoperativebleeding(morethan50mL)areassociatedwithlargertumorsize.Rectovaginalfistulaisreportedinfewerthan1.5%ofpatientsinlargeseries.Analdysfunctionandfecalincontinenceduetoanalstretchduringtheprocedurehavebeenhypotheticalconcernsduetothesizeoftheoperatingproctoscope,butseveralstudieshavedemonstratedthatfecalincontinencescoresdonotchangesignificantlyafterTEMorTAMIS,andlong-termfecalincontinenceisLocalExcisionofRectalCancer ConventionalLocalExcisionThe3mostimportantoutcomemeasureswithregardtoLEforrectalcancerarelocalrecurrence,disease-freesurvival,andoverallsurvival.Therearenoprospectiveran-domizedtrialscomparingconventionalLEwithradicalsurgery,andmoststudiesaresmallsingle-institutionreviews.ThereisgreatvariabilityinreportedoutcomesforbothlocallyexcisedT1andT2tumorsinthesestudies,reflectingthevariednatureofthestudiesthemselves.Localrecurrence,forinstance,variesfrom5%to28%withLEofT1lesionsand13%to37%forT2lesions.Disease-freesurvivalat5yearsisalsoarange:64%to93%forT1lesionsand63%to90%forT2lesions.Thesefind-ingscompareunfavorablywithradicalsurgeryforsimila

rlesions.Nevertheless,despitetheincreasedlocalrecurrenceseenwithLEofT1tumors,moststudiesdonotshowanystatisticaldifferencein5-yearoverallsurvivalascomparedwithradicalsurgery,althoughthetrendfavorsradicalsurgery.7,35–38ConventionalLEforT2le-sions,however,isclearlyinferiortoradicalsurgery.TransanalEndoscopicMicrosurgeryandTransanalMinimallyInvasiveSurgeryThebenefitofendoscopicandminimallyinvasiveresectionofrectaltumorsisanextendedanatomicrange,allowingaccesstomoreproximaltumorsthanconventionalexcision.Moreover,visualizationofthetumorisenhanced,leadingtoatheoreticoncologicadvantagewithimprovedmarginsandlessspecimenfragmentationwhencomparedwithconventionalLE.TherearenorandomizedstudiesthatdirectlycompareTEMorTAMIStoconventionalLE.Arecentmeta-analysisconcludedthatlocalrecurrenceratesarelowerwithTEMthanwithconventionalLE.SeveralstudiesdirectlycompareTEMwithradicalsurgery.AsinglesmallrandomizedtrialforT1tu-morsfoundnosignificantdifferenceinlocalrecurrenceoroverallsurvivalbetweenTEMandradicalsurgery.ThisisconsistentwithotherretrospectivestudiesforTEMinT1tumors.INDICATIONSTOPROCEEDWITHRADICALSURGERYBecauseoftheuncertaintythatsurroundsclinicalstagingofarectaltumor,LEmaybethoughtofasafull-thicknessbiopsy.ForpatientswithclinicallystagedT1tumorswhowanttopursueLEasadefinitiveresection,thefinaltreatmentplanshouldneverthe-lessbebasedonthefinalpathologictumorstage.Iftherearehigh-riskfeatures(seeTable1)afterLEorifthetumorisT2orgreater,radicalsurgeryshouldberecommen-dedinpatientsphysiologicallyfitforsuchanoperation.Otherindicationsforradicalsurgeryincludeinadequatecircumferentialmarginsorpiecemealextractionofthespecimen.Outcomesforpatientswhoundergodelayedradicalresectionofanearly-stagerectalcancerwithin30daysofinitialLEaresimilartothosewhoundergoimmediateradicalresection.Somepatientsmayrefuseradicalsurgerydespitehigh-riskfeaturesormoreadvancedtumorpenetration(T2orT3);underthosecircumstances,itiscrucialtoconveytheinferioroncologicout-comesforLEascomparedwithradicalsurgery,butultimatelyrespectthepatients’PosttreatmentSurveillanceStandardposttreatmentsurveillanceofrectaladenocarcinomaincludesclinicalabdominalanddigitalrectalexamination;CTimagingofthechest,abdomen,andpelvis;serialserumCEAlevels;andendoscopicevaluation.ForpatientswhohaveundergoneLEalone,theoptimalsurveillanceprotocolhasnotbeendetermined,Young&Kumar butamoreaggressivesurveillanceregimenmaybeapp

ropriatetoallowearlyidenti-ficationofrecurrence.Somestudieshavesuggestedroutineuseoftransrectalultra-soundandpelvicMRI.46,47Theauthors’favoredapproachadherestoprotocolsdesignedfornonoperativemanagementofrectalcancerinpatientswithacompleteresponsetochemoradiationtherapy,usingannualendoscopicsurveillanceofthewoundbedbyflexiblesigmoidoscopyforthefirst5yearsandassessingthelymphnodebasinbyalternatingendoscopicultrasoundsandpelvicMRI(rectalcancerstag-ingprotocols)spacedat3-monthintervalsduringtheyearafterresection.Theimagingintervalislengthenedto6monthsandthenannuallywithcontinuednegativefindings.ADDITIONALTHERAPYNeoadjuvantTherapyNeoadjuvantchemoradiationtherapycombinedwithradicalsurgeryhasbecomethestandardofcareforlocallyadvancedrectalcancerbecauseofevidencefordecreasedlocalrecurrence.ThishaskindledinterestedinapplyingthisapproachtoLE,especiallyinT2orT3rectalcancers,withthehopeofdecreasinglocalrecur-renceandavoidingradicalsurgery.Severalsmallstudieshavesuggestedimprovedlocaltumorcontrolwithneo-adjuvantchemoradiotherapyplusLE.AmulticenterphaseIIclinicaltrialusingLE(TEMorconventionalLE)afterneoadjuvanttherapyforT2N0rectalcancerrecentlyre-ported4%localrecurrenceand3-yeardisease-freesurvivalof88%,althoughitdidnotmeetitspredeterminedstatisticalthresholdforefficacy.Thisresultisneverthe-lesspromising,althoughsucheffortsremainwithintherealmofclinicalstudyandoutsidethescopeofstandardpractice.AdjuvantTherapyTheroleforadjuvantchemoradiationafterLEisnotwelldefined.Incontrasttothein-creaseoverrecentyearsinratesofLEforearly-stagerectalcancer,therehasbeenadecreaseinthenumberofpatientswhoundergoadjuvanttherapyafterLE.ThereisretrospectiveevidencesuggestingthatLEplusadjuvantradiationtherapymaybeequivalenttoradicalsurgeryaloneforoverallsurvivalinT1andT2tumors.ItisnotclearthatLEplusadjuvantradiationmaintainsthebenefitsofLEaloneintermsofqualityoflifeversusradicalsurgery.Atleast1randomizedtrialcomparingradicalsurgerytoLEpluschemoradiationtherapyforT1-2rectalcancersisplanned.TheprognosisforlocalrecurrenceafterTAEofT1adenocarcinomaispoorcomparedwiththoseinitiallyresectedwithradicalsurgery.Five-yeardisease-freesurvivalrangesfrom53%to79%despitesalvagetherapy.34,58,59Arecentsingle-institutionretro-spectivereviewfoundthatmostpatients(87%)withrecurrenceafterLEforT1rectalcancerwereabletoundergoasalvageoperation,although5-yearoverallsurvivalwasonly69%.Inadditiontothedram

aticdecreaseinoverallsurvival,sphincter-sparingapproachesthatwerepossibleatfirstpresentationmaynotbepossiblewithsalvagesurgery.Thisunderscorestheimportanceofpatientselection;itisespeciallycriticaltodiscussthesefindingswithpatientswhofalloutsidethestrictcriteriaforLEbutareaversetoradicalsurgery.SUMMARYLEforrectalcancerisenticingbecauseofthedecreasedmorbidityandmortalityascomparedwithradicalsurgery,butitisbestusedinhighlyselectedpatientswhoLocalExcisionofRectalCancer haveearly-stagecancerswithfavorablehistology.Itisalsoappropriateforthosewhootherwisewouldbeunfitorunwillingtoundergoamoreaggressivesurgicalapproach.OncologicoutcomesofLEareinferiortoradicalsurgery,butnewerliteraturesuggeststhatTEMandTAMISmaypartiallybridgetheoutcomesgapduetoimprovedvisibilityandlowermarginpositivity.Anylocallyexcisedtumor,regardlessofapproach,meritsmeticulousfollow-upandsurveillanceforlocalanddistantrecurrence.TheauthorsgratefullyacknowledgetheeffortsofAlexandriaJ.Kent,BA,foredito-rialandadministrativeassistanceinpreparationandsubmissionofthisarticle.Theau-thorsalsothanktheASCRSCRESTprojectforuseofthefiguresinthisarticle.PollardCW,NivatvongsS,RojanasakulA,etal.Carcinomaoftherectum.DisCo-lonRectum1994;37(9):866–74StewartDB,HollenbeakC,BoltzM.Laparoscopicandopenabdominoperinealresectionforcancer:howpatientselectionandcomplicationsdifferbyapproach.JGastrointestSurg2011;15(11):1928–38rezP,RodrrezS,VegaJ,etal.Morbidityandmortalityfollowingabdominoperinealresectionforlowrectaladenocarcinoma.RevInvestClin2001;53(5):388–95MccallJL,CoxMR,WattchowDA.Analysisoflocalrecurrenceratesaftersurgeryaloneforrectalcancer.IntJColorectalDis1995;10(3):126–32sJM,BordaN,LizerazuA,etal.Patternsoflocalrecurrenceinrectalcancerafteramultidisciplinaryapproach.WorldJGastroenterol2011;MorsonBC,BusseyHJ,SamoorianS.Policyoflocalexcisionforearlycancerofthecolorectum.Gut1977;18(12):1045–50YouYN,BaxterNN,StewartA,etal.IstheincreasingrateoflocalexcisionforstageIrectalcancerintheUnitedStatesjustified?AnnSurg2007;245(5):726–338.NationalComprehensiveCancerNetwork.Rectalcancer.Availableat:https://www.nccn.org/professionals/physician_gls/pdf/rectal_blocks.pdf.AccessedSeptember5,2016.RafaelsenSR,KronborgO,FengerC.Digitalrectalexaminationandtransrectalultrasonographyinstagingofrectalcancer:aprospective,blindstudy.ActaRa-diol1994;35(3):300–4NichollsRJ,MasonAY,MorsonBC,etal.Theclinicalstagingofrectalcanc

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