MSAC Application 1150

Final

Decision Analytic

Protocol (DAP) to guide the assessment of the insertion of colonic stents for the management of malignant bowel obstructions

15 August 2011

Table of Contents

MSAC and PASC

Purposeofthisdocument

Purpose of application

Intervention

Description

Administration,dose,frequencyofadministration,durationof treatment

Co-administeredinterventions

Background

Currentarrangementsforpublicreimbursement

Regulatorystatus

Patient population

ProposedMBSlisting

Clinicalplaceforproposedintervention

Comparator

Clinical claim

Outcomesand health care resources affected by introduction of the proposed intervention

Outcomes

Healthcareresources

Proposed structure of economic evaluation

Questions for public funding

References

MSAC and PASC

TheMedicalServicesAdvisoryCommittee(MSAC)isanindependent expertcommittee appointedbytheAustralianGovernment HealthMinistertostrengthentheroleofevidencein healthfinancingdecisions inAustralia.MSACadvisestheCommonwealth MinisterforHealth andAgeingontheevidencerelatingtothesafety,effectiveness,andcost-effectivenessofnew andexistingmedicaltechnologies andproceduresandunderwhatcircumstances publicfunding should besupported.

TheProtocolAdvisorySub-Committee (PASC)isastandingsub-committeeofMSAC.Its primaryobjectiveisthedeterminationofprotocolstoguideclinicalandeconomicassessments of medicalinterventionsproposed for publicfunding.

Purposeofthisdocument

Thisdocumentisintendedto provideadraftdecisionanalyticprotocolthatwill beusedtoguide theassessmentofanintervention foraparticularpopulationofpatients.Thisprotocolwillbe finalised afterinvitingrelevant stakeholderstoprovideinputtotheprotocol.Thefinalprotocol willprovide thebasis for theassessmentof theintervention.

Theprotocolguidingtheassessmentofthehealthinterventionhasbeendevelopedusingthe widelyaccepted“PICO”approach.ThePICOapproachinvolvesacleararticulation ofthe followingaspectsof thequestion(s)for publicfundingthattheassessmentisintendedtoanswer:

Patients–specificationofthecharacteristicsofthepatientsinwhomtheinterventionis tobeconsideredfor use;

Intervention– specificationof theproposed intervention

Comparator–specificationofthetherapymostlikelytobereplacedbytheproposed intervention

Outcomes–specificationofthehealthoutcomesandthehealthcareresourceslikelyto beaffectedbytheintroductionof theproposed intervention

Purpose of application

AproposalforanapplicationrequestingMBSlistingofcolonicstentsforthemanagement of malignantlargebowelobstructionwasreceived fromtheColorectalSurgical SocietyofAustralia and NewZealandbytheDepartmentof Healthand Ageingin October2010.

Intervention

Description

Colorectalcancer(ICD-10:C18–C20),whichisalsoknownaslargebowelcancer,isoneofthe mostcommoncancers intheworld.Thelargebowelconsistsoftheascendingcolon,transverse colon,descendingcolon,sigmoidcolonandtherectum.IntheUK,colorectalcanceristhethird mostcommoncauseforcancerdeathsandtheAssociationofColo-ProctologyofGreatBritain and Ireland states that approximately 100 new cases are diagnosed each day in the UK (ACPGBI, 2007).AccordingtotheNationalInstituteforHealthandClinicalExcellence inthe UK thefiveyearsurvivalrateafterdiagnosisof colorectalcancerisabout 45%and theremaining

50-60%of patientseventuallydevelopmetastases(NICE,2004,pp. 9;NCCN,2011).

InAustralia, colorectal canceristhesecondmostcommoncancer.In2007,prostatecancerwas themostcommoncancerreported with19,403newcases,followedbybowelcancer(14,234new cases)andbreastcancer(12,670 newcases)(AIHW,2010,pp.19). Inthesameyearlungcancer wasthemostcommoncauseofdeathfromcancerinAustraliacausing 7,626deaths, while colorectalcancertookthelivesof4,047Australians.Theincidenceofcolorectalcancerwas notedas 13.1%(males–12.6%,female–13.9%)ofoverallcancerincidencesin2007.According totheAustralianInstituteofHealthandWelfare,theincidencerateofcolorectalcancerinmales increasedfrom67to 75casesper100,000andinfemalesfrom50to55 casesper100,000during theperiodfrom1982to2007(AIHW, 2010).TheInteractiveNationalHospitalMorbidityData confirmstheutilizationof12,919patientdaysofmalignantneoplasmofthecolonduring

1998/99, whichannuallyincreased upto19,037patientdaysby2007/08(dataaccessedthrough

15March 2011).

Intestinalobstructionisacommoncomplicationandrelatedmedicalemergency amongpatients whosufferfromcolorectal cancer.Canceristhesecondmostcommoncauseofintestinal obstructioninadultsfollowingadhesionssecondarytopriorlaparotomy,whilecolorectaland ovariancancersarethemostcommoncausesofmalignantcolorectal obstructions (DavisNouneh, 2001;Wattetal,2007).Intestinalobstructionsmayalsobecausedbyothernon- malignantconditionssuchasCrohndiseaseanddiverticulitis. Theincidenceofintestinal obstructionsduetoprimaryintestinalmalignanciesrangesfrom10–28%(DavisNouneh,

2001;Tilneyetal,2007).Mandavaetal(1996)statedthatabout30%ofcoloncancerpatients

and10%ofrectalcancerpatientspresentasemergencies and80%ofsuchcomplications were relatedtocolorectalobstruction. Xinopoulosetal(2004)citedthat10-20%ofcolorectalcancer patientsdeveloppartialcolonicobstruction while8-29%leadtocompleteobstruction.The majority,75%ofsuchobstructions, havebeenlocatedintheleftsideofthecolon,descending colonandtherecto-sigmoid regionmakingthemaccessiblebycolonoscopicmeans(data provided in theapplication).

Colonicstentsinmanagingcolorectalobstructionhavebeenusedsincethelastdecade.Self- expandingmetallic stents(SEMS) arethemostcommoncolonic stents.Absorbablestentsare startingtobeusedforcolonicindications.Thesehavethebenefitofreducedmigrationdueto thefactthattheyare absorbed withinapproximately one month.

SEMSareexpandablemetallic tubesthatareadopted forthereliefofmalignantcolorectal obstruction,asaminimallyinvasivealternativeproceduretoopensurgicaltechniques(Watt,

2007).Placementofastentattheobstructedpartofthecolonallowsmanagementofthe

emergencyandtimetoplanelectivesurgery,servingasa‘bridgetosurgery’.Inadditionthe stentingprocedurecanbeusedforpalliativemanagementofbowelobstruction amongpatients whosufferfromincurablemetastaticdiseasesandinwhommajorresectionsarenotappropriate. Thestentingtechniquecanalsobeusedtotreatbenignobstructionscausedbyconditionssuch asdiverticularand Crohn disease,butSEMS arenot listedon theARTGfor theseconditions.

Colonicstentscouldbeclassifiedasmetallicornon-metallic.InAustraliaingeneralonlymetallic stentsareused;thesecanbe‘covered’or‘uncovered’. CoveredSEMScanbefullyorpartially covered,whilethemajorityofstentsusedinAustraliaareoftheuncoveredtype. Differenttypes ofmetalsoralloyscanbeused;allstentshaveameshdesign.Theyaredeployed overadelivery catheterand self-expandoncetheyaredeployedduetoradial force.

Stentmigration,obstruction,tissueingrowthandbowelperforationareadverseeventswhich maybeassociatedwithstentdeployment. Accordingtoexpertclinicianinput,uncoveredSEMS mayreducepost-operative complications suchastissuereactions,henceminimisingtheriskof stentmigration;whilegranulationtissue/tumouringrowthmaybelesscommonwithcovered SEMS.

Themetallic stentsapprovedforuseinAustraliafollowinTable1(Wattetal,2007).Thestent whichhasbeennamedaspartoftheapplicationisARTG119517,whichisestimatedtohave

85%ofAustralianmarketshare.Expertclinicalopinionsuggeststhatthereislittleclinical

difference betweenthestentscurrentlyavailableintheAustralianmarket.However, whilesome ofthelistedstentsmaybeusedforobstruction causedbyunspecified malignancy (ARTG numbers119517,157191),otherstentsarerestrictedtouseinthecaseofobstructions caused specificallybycolorectalcancer(ARTGnumbers139317,144564,167223).Duodenalstentsare

also listed on the ARTG; however, expert input has confirmed that these would not be appropriate tousein thetreatmentof colorectalobstructions.

Table1.TGAapproved stentingdevicesandsystemsfortreatingcolorectalobstruction

ARTG No

Manufacture/ Importer/ Sponsor

Device nameGMDNIntendedpurpose

119517*Boston ScientificPty

Ltd

119517*Boston ScientificPty

Ltd

119517*Boston ScientificPty

Ltd

157191William A.Cook

AustraliaPtyLtd

139317William A.Cook

AustraliaPtyLtd

144564EndotherapeuticsPty

Ltd.

167223DeviceTechnologies

AustraliaPtyLtd.

Ultraflex™Precision ColonicStentSystem Wallstent®Enteral colonicEndoprosthesisWallFlex®Colonic Stents

Cook Colonic Z-Stent®

withinductionsystem

38442

Unclassified

37847

ColonicStent

37847

ColonicStent

37847

ColonicStent

37847

ColonicStent

Palliativetreatment ofgastro-duodenal obstructionsandcolonicstricturesproduced bymalignancy.

Palliativetreatmentforcolonic,duodenalor gastricobstruction orstrictures causedby malignant neoplasm, and to relieve large bowelobstructionpriortocolectomy in patientswithmalignant strictures.

Maintainpatency ofmalignantcolonic strictures.

Palliative treatment of colonic strictures causedbymalignantneoplasmintherectum, sigmoidcolonanddescendingcolon. Implantedforpre-operativeobstructionrelief prior to removal of colo-rectal carcinoma, designed to maintain the patency of colo- rectalstricturescausedbymalignanttumour.

*BostonScientificPtyLtd WallFlex®ColonicStentsarenewgenerationstentsandaccountfor85%ofAustralianmarketshare Ultraflex™

andWallstent®arefirstgenerationstents

Administration,dose,frequencyofadministration,durationof treatment

Thecolonicstentsusedinmanagingcolorectalobstructionhavebeeninusesincethelast decade.Placement ofastentattheobstructedpartofthecolonallowsclinicianstomanagean emergencysituationandtoplananelectivesurgery.Emergency resectioncouldleadtoserious complications, ifperformedinpatientswhoarealreadyfrailandsufferingfromsignificantco- morbidities(NICE,2004). Inadditiontousingthestentingprocedure asa‘bridgetosurgery’,it isalsoapalliative alternative forbowelobstructionamongpatientswhosufferfromincurable metastatic diseasesoraremedicallyunfitformajorresections (forexamplepatientswhoare unable to receiveanaesthesia)(ACPGBI,2007). A stent obviatesthe need for stomaor resection,and isusuallyeffectivefor over a yearand can oftenprovide palliation untildeath.

Stentingofmalignantcolonicstricturesisaminimallyinvasiveendoscopicprocedurerequiring noincision.Itisusualforcolorectalstenting tobecarriedoutunderconscioussedationwithout generalanaesthesia (Wattetal,2007).Theprocedure takesbetween30–90minutes.Stent insertionwouldnotbesuitableforobstructionsofthemostproximallargebowel;deployment ofthestentintheremainingpartsofthecolonisperformedusuallyathospitalsequipped with resources in managing bowel obstructions. Thus, facilities with appropriately trained endoscopists,operatingtheatres,anaesthetistsandradiologyserviceswouldbenecessary.The procedureisundertakenbyacolorectalsurgeonorgastroenterologistappropriatelytrainedin

thisprocedureandcertifiedbytheConjointCommitteeforRecognition ofTrainingin Gastrointestinal Endoscopy(CCRTGE).Thedeploymentsystemconsistsofawireorcatheter. SEMSrequireanobstructiontoholdtheminplace;iftheobstructionbecomesreducedasa resultof medicalmanagementthenthestentislikelytosimplyfall out.

Re-stenting (theplacement ofasecondstentoverthefirststent)mayoccurininstanceswhere tumourovergrowth occurs.Re-stenting wouldbealsonecessaryincaseofmigrationofa deployedstent.Accordingtoexpertclinicalinput,re-stenting usuallywouldbeattemptedupto twotimes,and isunlikelytobeattempteda thirdtimeiftheinitial twoattemptsare unsuccessful.

Co-administeredinterventions

Aclinicaldiagnosisofbowelobstruction istobeconfirmedbyeitherCTscanoranabdominal radiograph. Excluding pseudo-obstructionis also an important step of the procedure and contrastenema(Gastrografinenema)or endoscopy(sigmoidoscopy)maybeusefulin this.

Onceclinicaldiagnosisisconfirmed,thestentcanbedeployedunderfluoroscopic control, colonoscopiccontrolorbytheuseofbothtechniques(Libermanetal,2000;Camunezetal,

2000;Saida,1996).Abdominalradiographymaybeusedatintervals inthefirstfewdaysafter stent placementtoascertainthatthestent hasremainedcorrectlyplacedandthattheobstructing lesionispatent.

Patientsarelikelytoreceiveongoingactivemedicalmanagement followingthedeploymentofa stent.Themedicalmanagementconsistsofchemotherapy,radiotherapyoracombinationof thesewitheithercurative orpalliative intent. Accordingtoexpertclinical opinion,theexacttype orcombinationofmedicalmanagement receiveddependsonthepatients’statusandis individuallybased.

ThemajorityofstentsusedinAustraliaareuncoveredSEMSduetothereducedincidence of post-operative complications suchastissuereactions,henceminimizingchancesofstent migration.Incaseofmigration,amigratedstentwouldberemoved, andanewstentwouldbe deployedacrosstheobstructedpartofthebowel.Placingonestentoveranotherisalsopossible, iftheinitial stentbecomesobstructedbygranulation tissueor tumour.

Background

Currentarrangementsforpublicreimbursement

Surgicalresectionis thestandardtreatmentformanagingcolorectalobstructionatpresent.Acute obstruction secondary to colorectal cancer is considered as a surgical emergency, and is associated with a higher risk than comparable elective surgery (McArdle Hole, 2004).

Xinopoulosetal(2004)statethatabout50%ofpatientspresentingwithmalignantcolorectal obstructionareeligiblefor curativeresectivesurgery.

Table2showscurrentMBSitemnumbersrelatedtoresectionandmanagementofcolorectal obstruction. Table3showsthenumberofservicesclaimedforeachitem.Colostomyisthe standardprocedureforbowelobstruction causedbynon-resectablecancers,eventhoughstoma creationhasapoorimpactonpatients’psychologicalwellbeing andcouldbeaburdentocarers,

aswellasthepatient,during thefinal months of life(Karadag etal, 2003).

Table2. Typesof resectionprocedureslistedontheMBSformanagingcolorectalobstructions
MBS
itemno / Typeof resectionprocedure / Fee(asof
April 2011) / Benefit(asof
April 2011)
30375 / Categoryno: 3TherapeuticProcedures / $501.50 / 75%=$376.15
MBS description: Caecostomy, Enterostomy, Colostomy, Enterotomy,
Colotomy,Cholecystostomy, Gastrostomy,Gastrotomy,Reductionof intussusception,RemovalofMeckel'sdiverticulum,Sutureofperforatedpeptic ulcer,Simplerepairofrupturedviscus,Reduction ofvolvulus,Pyloroplasty (adult)orDrainageof pancreas
32024 / Categoryno: 3Therapeuticprocedures / $1,312.90 / 75%=$984.70
MBS description: RECTUM, HIGH RESTORATIVE ANTERIOR
RESECTIONWITHINTRAPERITONEAL ANASTOMOSIS(ofthe rectum)greaterthan10centimetresfromtheanalvergeexcludingresection of sigmoidcolonalonenotbeingaserviceassociatedwithaservicetowhichitem
32103,32104or 32106applies
32033 / Categoryno: 3TherapeuticProcedures / $1,450.30 / 75%= $1,087.75
MBS description:RESTORATIONOFBOWELfollowingHartmann'sor
similar operation,includingdismantlingofthestoma
32009 / Subtotalor totalabdominal colectomy / $1,312.90 / 75%=$984.70
Categoryno: 3TherapeuticProcedures
MBS description:TOTALCOLECTOMY ANDILEOSTOMY
32025 / Categoryno: 3Therapeuticprocedures / $1,756.15 / 75%=$1,317.15
MBS description: RECTUM, LOW RESTORATIVE ANTERIOR
RESECTIONWITHEXTRAPERITONEAL ANASTOMOSIS(ofthe rectum)lessthan10centimetresfromtheanalverge,withorwithoutcovering stoma notbeingaserviceassociatedwithaservice towhichitem32103,32104 or 32106applies
32026 / Categoryno: 3Therapeuticprocedures / $1,891.20 / 75%=$1,418.40
MBSdescription:RECTUM,ULTRALOWRESTORATIVERESECTION,
with orwithout coveringstoma,wheretheanastomosisissited intheanorectal
region andis6cmorlessfrom theanal verge
32003 / Categoryno: 3Therapeuticprocedures / $1,037.95 / 75%=$778.50
MBS description: LARGE INTESTINE, resection of, with anastomosis,
includingrighthemicolectomy

Therespective numberofservicesutilizedforeachitemnumberisshowninTable3.Figures showaclearincrement ofdemandandutilizationfrom1997to2010.HowevertheaboveMBS itemnumberscouldalsobeusedtomanageotherindicationsincludingdiverticulardiseases, pelvicabscesses,Crohndiseaseandtraumainadditiontomalignantbowelobstructions.The applicationindicatesthatthevastmajorityofbowelresections performedareinthesettingof non-obstructing electiveresectionofbowelcancer.Asthesameitemnumbersareusedinthe emergencysetting,thereisnowaytodeterminefromthesefiguresthefrequencywithwhich resectionisperformedforcolorectalobstruction.Useofeachitemcouldalsodependonthe levelandcauseoftheobstruction, thepatient’sconditionandseverityofdisease,aswellasthe surgeon’spreferenceandexpertise.

Table3. Thenumberof servicesclaimedforeachMBSitemnumber
Financial year / 30375 / 32024 / 32033 / 32009 / 32025 / 32026 / 32003 / Total
2009/10
2008/09
2007/08
2006/07
2005/06
2004/05
2003/04
2002/03
2001/02
2000/01
1999/2000
1998/99
1997/98 / 2,316
2,196
2,073
1,987
1,902
1,931
1,882
1,934
1,969
2,041
2,032
1,948
1,981 / 1,698
1,717
1,793
1,714
1,692
1,624
1,541
1,559
1,502
1,378
1,300
1,249
1,152 / 324
332
329
291
310
298
267
281
283
220
233
237
286 / 128
129
107
119
108
113
110
90
98
97
64
80
84 / 1,032
995
1,005
988
949
964
890
879
852
836
686
650
687 / 821
808
885
828
753
719
668
665
641
597
459
516
434 / 3,701
3,544
3,542
3,358
3,365
3,135
3,003
3,125
2,869
2,832
2,579
2,443
2,420 / 10,020
9,721
9,734
9,285
9,079
8,784
8,361
8,533
8,214
8,001
7,353
7,123
7,044

Regulatorystatus

Relevantcolonicstentsarelistedon theARTG(Table1.).

Patient population

Insertionofcolonicstentsisproposedfortreatmentoflargebowelobstruction,strictureor stenosisin thefollowingpatientpopulations:

1. Patientsdiagnosedwithcolorectalcanceror cancerof an organ adjacenttothebowel:

a.Stentasapalliativemeasureforpatientswithincurablemalignantlargebowel obstructionwitheitherchronicoracuteco-morbidities, withorwithout metastasis.

b. Stentasabridge-to-surgery, incasethepatient’sconditionimprovesafter insertion of a stent/sand subsequentsurgicalmanagementisthenindicated.

2. Patientspresentingwithlargebowelobstructionofunknowndiagnosis.Thisgroupof patients maynotalwaysbeknowntohavecanceratthetimeofthebowelobstruction. Patients with non-malignant causes of obstruction such as Crohn disease and diverticulitismayalso bepart of thispopulation:

a.Stentasapalliativemeasureforpatientswithincurablemalignantornon-

malignantobstructionwitheitherchronicoracuteco-morbidities,withor withoutmetastasis.

b. Stentasabridge-to-surgery, incasethepatient’sconditionimprovesafter insertion of a stent/sand subsequentsurgicalmanagementisthenindicated.

Thesubsequentsurgicalmanagement ofanystentedpatientmaybeanytypeofsurgical intervention includingcurativesurgeryornon-curativesurgery,single-stage resectionoramulti- stageprocedure.

Forthepurposesoftheassessment, patientswhocanreceivesinglestagecolorectalresection shouldreceivethisoptionwhereappropriate;thereforetheuseofstentsisnotindicated inthis population.

ProposedMBSlisting

Table4showstheproposed MBS itemdescriptor.

The2010proposedfeefortheinsertionofacolonicstentis$650.Thefeeutilised forthe assessment reportneedstobeindexedby2011and2012WageCostIndex(WCI5)rate. According to the application, this fee includes the fee for colonoscopy to the point of obstruction,passageofaguide-wireacrosstheobstructionunderfluoroscopyanddeployment ofacolonicstent.Thetechnicaldifficultyofthisprocedureexceedsthatfordeployment ofan oesophagealorbiliarystent.Thereliefofobstructionisaccompanied byimmediateandoften dramaticpassageofstoolwhichcanbeextremelyunpleasantfortheproceduralistandother teammembers.Proceduralduration ranges from 30-90minutes.

ItissuggestedthattheMBSitemdescriptor shouldnotlimitrepeatuseofstents.Itisunlikely thatre-stentingwouldbeattempted onmorethanthreeoccasions–ifthereweretwoormore failures,analternativeapproachwouldbetaken.However,itmaybethatstentswouldneedto beinsertedin separatelocationsin thesameindividual.

Table4:ProposedMBSitemdescriptorforinsertionofcolonicstentsforlargebowel obstruction,strictureorstenosis

Category3 –Therapeutic procedures

MBS [item number] [Item descriptor]

Endoscopicinsertionofstentorstentsforlargebowelobstruction,strictureorstenosis,wherecauseof the obstruction is dueto:

‐a pre-diagnosed colorectalcancer orcancer ofan organ adjacent tothe bowel.

‐an unknowndiagnosis. (Anaes.)

Fee:$650

[Relevant explanatory notes]

*Thefeefortheinsertionofacolonicstentcoversthecolonoscopytothepointofobstruction,strictureor stenosis,passageofa guidewireunder fluoroscopyand deployment ofa colonic stent.

*TwocolonicstentsarelistedontheARTGforuseincolonicobstructioncausedbymalignancy(ARTGnumbers

119517,157191). Theremainingthreecolonicstentsarelistedforuseinstricturescausedbycolorectalcancer

(ARTG numbers 139317,144564, 167223).

*Anaes.itemnos.20810and23063(or23031,23032,23033,23041,23042,23043,23051,23052,23053,23061,

23062)to be charged withtheserviceaccordingly.

*Theprocedureisundertakenbyacolorectalsurgeonorgastroenterologistappropriatelytrainedinthisprocedure

andcertified by theConjoint Committeefor RecognitionofTraining inGastrointestinalEndoscopy (CCRTGE).

Accordingtodepartmentalinput,inthecaseofafailedattemptatstentinsertion,thereisa genericMBSitemno(30001)tocoverfailedsurgicalinterventions where50%oftheusualfee couldbeclaimed.

Ifanobstructionorstenosisbecomes reducedthenastentwilllikelysimplyfallout,asthestent requiredanobstruction tokeepitinplace.Thismayalsooccurinthecaseofstentmigration. Thereforethereisno needtohavea specificMBS itemnumberfor stentremoval.

Clinicalplaceforproposedintervention

Currentclinicalmanagementofintestinalobstructioncausedbycolorectal cancerfollowsin Figure1andtheproposedclinicalmanagementalgorithmwiththeadditionofstentingasan optionfollowsintheFigure2.Ineachcase,theoverallpopulationwiththerelevantmedical conditionisdividedintothecolorectalobstruction(strictureorstenosis)dueeithertopreviously diagnosed cancerorofunknowndiagnosistomakeinterpretationoftheflowchart clinically meaningful.Althoughthestructuresoftheclinicalmanagementalgorithmsappearsimilaracross thetwosettings,thishelpsreflectdifferencesintheproportionsofpatientssuitableforeach individual pathwayacrossthetwoalgorithms.

Forthepurposesoftheflowchart, eachpopulationhasthenbeenfurthersplitintosub- populations – thosemedicallyfitfor surgeryand thosemedicallyunfitfor surgery.

Forthosemedically fitforsurgery,thereisadistinctionbetweenthosepatientsforwhomsingle stagesurgery(resection) isintendedtobothcurethemoftheircancerandtoremovethe obstruction;andthosepatientsforwhomsomeotherformofsurgeryisrequired.However,the figuresincludethepossibilityofmovement toanotherformofsurgeryiftheintendedsingle- stagesurgeryneedstobechangedforsomereasonduringtheprocedure.InFigure2,for patientswhoachievecurethroughsinglestagesurgery,insertionofastentisnotincluded asa relevantalternative option.Insertionofastentisincludedasarelevantoptionforallother patientsmedicallyfitfor surgery,whethercolostomyor Hartmann’s resection.

Colostomy isgenerallyperformedifthecanceristooadvancedorpatientisunfitdueto comorbiditiesofthedisease.Hartmann’sresectioniscommonlyperformedincaseofaless advancedcancerand whenthepatientiscomparativelyfitter.

Forthose patientsmedicallyunfitforanysurgery,bestsupportivecare(with anycombinationof chemotherapy, radiotherapyorpalliation)currentlyprovidestheonlyoption.InFigure2, insertionofastentwouldbearelevantalternativeoptiontobestsupportivecare.Thisgroupof patientsstillcouldimprove duetoongoing activemedicalmanagement.

Patientsarelikelytoreceive(orcontinuereceiving)medicalmanagementfollowingdeployment ofastent.Themedicalmanagementconsistsofchemotherapy, radiotherapy,palliationand/or combinationofafewmedicaltreatments. Accordingtoclinicians,thetypeofandcombination of medicalmanagementreceiveddependson eachpatient’sstatusand isindividuallybased.

Followinganunsuccessfulstentdeployment,usuallypatientsreceivecolostomy(majority)ifthey weretoundergosurgery.Incaseofunsuccessfulstentdeploymentduetobowelperforation, theywouldreceiveHartmann’sresectionforcorrection accordingtoexpertclinicalinput.Ifthe stentneedstoberemovedduetoacomplication, thiswouldbealsochargedasaHartmann’s; alternativelyifthestentmigratesbeyondtheobstructionthenitislikelytosimplyfallout.

Large bowel obstruction, stricture or stenosis

Patientswith colorectal obstruction due to an unknown

diagnosis

Patientswith colorectal obstruction due to pre-diagnosed

cancer

Medicallyfitforsurgery

Medicallyunfitforsurgery

Medicallyfitforsurgery

Medicallyunfitforsurgery

Duringprocedure curenotpossible ormultistage

surgeryrequired

Duringprocedure curenotpossible ormultistage surgeryrequired

Intendedsinglestage curativesurgery*

Othersurgery*

Bestsupportive care*

Intendedsingle stagecurative surgery*

Other surgery*

Bestsupportive care*

Nofurther surgical

management

Subsequentsurgical managementasindicated

Nofurther surgical management

Subsequentsurgical managementasindicated

Nofurther surgical management

Note

1. Othersurgery:twoandthreestagedresectiontechniquesusedinmanagingcolorectalobstructions,stricturesorstenosis.Hartmann’sprocedureandprimaryanastomosiscouldbeperformedbyitselfor together withstagedsurgicalresections.CurrentMBSlistedsurgicalresectiontechniquesarelistedinTable2.

2. Subsequentsurgicalmanagement:anysurgicalinterventionincludingsinglestagesurgeryand‘other’surgery.

3. Bestsupportivecare:conservative/clinicalmanagementofsymptomswithoutsurgicalinterventions.

* Patientswouldalsoreceivechemotherapy,radiotherapyand/orpalliationin additiontoongoingmedicalmanagement.Thetypeandcombinationof medicalmanagementreceivedis individuallybased.

Figure 1. Current clinicalmanagement algorithm

Large bowel obstruction, stricture or stenosis

Patientswith colorectal obstruction due to an unknowndiagnosis

Patientswith colorectal obstruction due to pre-diagnosed cancer

Medicallyfitforsurgery

Medicallyunfitforsurgery

Medicallyfitforsurgery

Medicallyunfitforsurgery

Duringprocedure: curenotpossible ormultistage

surgeryrequired

Stentfailure during procedure

Duringprocedure: curenotpossible ormultistage

surgeryrequired

Stentfailure during procedure

Intendedsingle stagecurative surgery*

Stent*

Other surgery*

Stent*Bestsupportive care*

Intendedsingle stagecurative surgery*

Stent*Other surgery*

Stent*

Bestsupportive care*

Nofurther surgical management

Subsequent surgical managementas

indicated

Subsequent surgical managementas

indicated

Nofurther surgical management

Subsequent surgical managementas

indicated

Subsequent surgical managementas

indicated

Nofurther surgical management

Note

2. Subsequentsurgicalmanagement:anysurgicalinterventionincludingsinglestagesurgeryand‘other’surgery.

3. Bestsupportivecare:conservative/clinicalmanagementof symptomswithoutsurgicalinterventions.

* Patientswouldalsoreceivechemotherapy,radiotherapyand/orpalliationinadditiontoongoingmedicalmanagement.Thetypeandcombinationof medicalmanagementreceivedis individuallybased.

Figure 2. Proposed clinical management algorithm

Comparator

Surgical management

Surgicalresectionisthegoldstandardtreatmentinmanagingcolorectalobstructionatpresent.It maybecarriedoutasaone-stage,two-stageoreventhree-stage procedure. Forrightandleft sidedmalignancies,ahemi-colectomy withanastomosisispreferablyperformedasaone-stage procedure:thediseasedsectionofbowel isexcisedandremoved,andthefreeendsofthebowel arere-joinedduringthesameproceduretorestorebowelfunction.Accordingto clinicalopinion, singlestageresectionandanastomosisisthepreferredoptionformanagement oflargebowel obstruction, butclearlynotallpatientsortumoursarecandidatesforsinglestagesurgery.This mayrelatetovariousfactorsincludingpatientcomorbidity, tumourstageorsize,surgeon experienceorexpertise.Singlestagesurgeryalsorequiresgreatersurgicalexpertise(morethan forelectivesurgeryingeneral).Inaddition,duetoitsincreasedinvasiveness, themorbidityof singlestagesurgeryispotentiallygreater.

Fordistalleft-sidedmalignancies, two-stageproceduremayalsobeundertaken.Atwo-stage procedure involvesresectionofthebowelandtheformationofastoma,followedbyasecond operationtorestorebowelcontinuity(Hartmann’sprocedure).Alternatively, thestomamaybe closedduringathirdprocedure(DeSalvoetal,2002).However,asignificantproportionof patientsreceivingastagedprocedureneverundergoreversalofthecolostomy(Mauroetal,

2000).Colostomyisgenerallyperformedifthecanceristooadvanced orthepatientisunfitdue tocomorbidities thatmaybeunrelatedtothecancer.Hartmann’sresectioniscommonly performedincaseofalessadvancedcancerandwhenthepatientiscomparativelyfitter. Itis currentlyunclearwhetherasingleorstagedresectionis saferormoreeffective,butit is clearthat emergency surgerycarriesahigherriskthanelectivesurgery(DeSalvoetal,2002;McArdle& Hole,2004).

CurrentlyMBSlistedmethodsofresectionarelistedinTable2andTable3showsthenumber ofservicesclaimedforeachitem.Resectionand anastomosisisthe preferredpracticeforcolonic cancerswithobstruction, unlessthereisoverwhelming sepsiswithgeneralisedperitonitis,orthe patientisveryfrailandsick(CCAACN,2005).DespiteRCTdatashowingnosignificant benefitfromthestagedprocedure,resectioncan be alsoperformedbytheHartmann’stechnique with anendcolostomy(De Salvoetal,2002;CCAACN,2005).Occasionally,adivertingloop ileostomy isusedtoprotecttheanastomosis afterasegmental resection.NHMRClevelof evidenceIII-2studiessuggestthatprimaryanastomosisshouldbeconsideredasacolectomy, withanileocolicorileorectal anastomosis.Theyalsosuggestprimaryanastomosiscouldbe consideredforleft-sidedobstruction andmayneedtobeprecededbyon-tablecoloniclavage. Withprimaryanastomosis,thefollowing optionsareavailableaccordingtotheCancerCouncil Australia and AustralianCancer Network(2005):

Appropriateresectionandaprimaryanastomosisaccompaniedbyon-tableirrigationora modifiedbowelpreparation.

Subtotalcolectomywithileorectalanastomosis.

Bestsupportivecare

Whilethemajorityofpatientswouldbeeligibleforatypeofcurativeornon-curative surgical resection,patientsmedicallyunfitforsurgicalmanagement wouldreceivebestsupportivecare. Thesupportivecareforcancer patientsisthemultiprofessionalattentiontothepatient’soverall physical,social,psychosocial,spiritualandculturalneeds,andshouldbeavailableatallstagesof theillnessincludingdeathandintobereavement; forpatientsofallages,andregardless ofthe currentintentionofanyanti-cancer treatment. Ithelpsthepatienttomaximizethebenefitsof treatment andtoliveascomfortablyaspossible(NICE,2004;Ahmedzaietal,2001).Best supportivecareforpatientswhosufferfromadvancedgastrointestinalcancershouldbenefit bothsurvivalandqualityoflifebyacombinationofchemotherapyandsupportivecare(Ahmed etal,2004).Thereforeapatientwhoreceivesbestsupportivecarecouldimprovedue toongoing medicalmanagement.

Othersurgicalmanagement

Inaddition,theendoscopicablationtechniquessuchascryotherapy,electrocoagulation, argon plasmacoagulationandphotodynamictherapy,Nd:YAG(Neodymiumyttriumargongarnet) lasertherapyhavealsobeenusedinmanagingcolorectalobstruction(Kimmey, 2004).Laser therapycouldrestorepatencywhenusedonitsown;however,re-obstructionusuallyoccurs quiterapidly.Balloondilationanduseofdecompression tubesareotheralternativetreatments usedinmanagingcolorectalobstruction.Accordingtoclinicalexpertadvice,theseothersurgical management techniques are rarely used in the Australian context, hence have not been consideredascomparatorsin thisreview.

Clinical claim

Table5: Classificationofan interventionfordeterminationofeconomicevaluation to bepresented

Comparativeeffectivenessversuscomparator
Superior / Non-inferior / Inferior
Comparativesafety versuscomparator / Superior / CEA/CUA / CEA/CUA / Netclinicalbenefit / CEA/CUA
Neutralbenefit / CEA/CUA*
Netharms / None^
Non-inferior / CEA/CUA / CEA/CUA* / None^
Inferior / Netclinicalbenefit / CEA/CUA / None^ / None^
Neutralbenefit / CEA/CUA*
Netharms / None^

Abbreviations:CEA=cost-effectivenessanalysis;CUA= cost-utilityanalysis

*Maybereducedtocost-minimisationanalysis.Cost-minimisationanalysisshouldonlybepresentedwhentheproposed

servicehasbeenindisputablydemonstratedtobenoworsethanitsmaincomparator(s)intermsofbotheffectiveness and safety,sothedifferencebetweentheserviceandtheappropriatecomparatorcanbereducedtoacomparisonofcosts.In mostcases,therewillbesomeuncertaintyaround sucha conclusion(i.e.,theconclusionisoftennot indisputable).

Therefore,whenanassessmentconcludesthataninterventionwasnoworsethanacomparator,anassessmentofthe uncertaintyaround thisconclusionshouldbeprovidedby presentationofcost-effectivenessand/or cost-utilityanalyses.

^ No economicevaluationneedstobepresented;MSAC is unlikelyto recommendgovernmentsubsidyofthisintervention

Outcomesand health care resources affected by introduction of the proposed intervention

Outcomes

Stentswillnotcurecancer,whichisthecauseofobstruction,buttheymayreducethe frequency ofobstructionsoremergencyresections.Thefollowingeffectivenessandsafetyoutcomesofthe interventionhavebeenidentified.

Effectiveness

Primary outcomes

Qualityof life,estimatedoverall asquality-adjustedlife-years(QALY)gained

Ifastentsuccessfully deployed,patientswouldhavehigherqualityoflifecomparedtostoma creation,whichhas a poor impacton thepatients’psychologicalwellbeingand couldbea burden tocarers,aswellasthepatient,during thefinal months of life(Karadag etal, 2003).

Secondaryoutcomes

Technicaland clinicalsuccess

Technicalsuccessofthestentingprocedurecanbedefinedas‘successful stentplacement and deployment’ whereasclinicalsuccesscanbedefinedas‘colonicdecompression within96hours withoutendoscopicorsurgicalreintervention aftersuccessfulstentplacementanddeployment’ (Khotetal,2002).Accordingtoclinicalexpertadvicetechnicalsuccessofthisprocedureis about 95%,whileclinicalsuccessisapproximately 90% in Australia.

Asuccessfuloutcomefromthecomparativesurgicalresections,‘other surgery’,could bedefined as survivalwithoutmedicalorsurgicalcomplicationsaccordingto the clinicians.Anunsuccessful outcomeof ‘othersurgery’isdeathor major complicationasa resultof sucha surgicalresection.

Survival/mortality(eg.at30days)

Temporary or permanent reliefof obstruction

Avoidanceofmultistagesurgery

Avoidanceof emergencysurgery

Re-stenting

Hospital andICU stay

Operating time

Safety

Procedure-relatedmortality

Theprocedurehas a mortalityriskof approximately5%,according totheapplication.

Morbidity

Stentmigration

Bowelperforation

Stentblockage,obstructionor re-obstruction

Tumouringrowth/overgrowth

Haemorrhage

Postoperativepain and/or discomfort

Ulceration

Fistulaformation

Table6listspotentialbenefitsof colonicstentsaccordingtotheliterature(Khotetal, 2002).

Table6. Potentialbenefitsof colonicstentinsertion
‐Reduceoverall lengthof ICU and hospital stay
‐Reducepostoperativemorbidityand mortality
‐Reduceriskof complications
‐(Minimal or) no needfor abdominal incisions,bowelresectionor stomaformation
‐Allow timeforbowelpreparation and electivesurgery
‐Temporary or permanent reliefof obstruction.
‐Able toeatimmediatelyaftertheprocedure
‐Savenumber of resectionsin managing obstructions

Healthcareresources

The application estimatesannual stent deploymentusing data from the Australian Cancer Registry(AIHW,2004).Thishasbeenadapted toreflectthelatestAustralianCancerRegistry (AIHW,2010)data. Accordingly,outof14,000newcasesofcolorectalcancer,approximately

20%(about2,800)areestimatedtopresentwithobstruction.Nearly75%ofthese2800patients (approximately2100)willhaveleftsidedmalignanciesamenabletoendoscopicmanagement. Onethirdofthesewouldhavemetastatic diseases(700)andanother20%(400)wouldbe medically unfitforsinglestagesurgery.Overall,approximately1,100patientsperyearwouldbe suitableforstenting. Allowingforexistinglocalvariabilityinexpertise andfacilities, aswellas individualsurgeonorpatient biasandpreference,theassumptionofanannualstentdeployment rateof 575-625asprovided in theapplicationappears tobea fair estimate.

According to the application, in 90%of cases,stentingwill replaceemergencyabdominal surgery.Following stenting,inabout10%cases,patientswillrequiresurgeryforfailedstent placement.Afurther10% willreturnfordefinitivesurgeryafter initialdecompression.Assuming

90%technicalsuccess,onewouldexpect550feweremergency abdominalprocedures peryear (eitherHartmann’sprocedure,anteriorresectionwithantegradecoloniclavageorlaparotomy withformationofcolostomy/ileostomy)performedforlargebowelobstruction.Approximately

10%ofstentscurrentlyusedaredeployedas abridge to definitivesurgery,andthereforepatients

willultimatelyreturnforsinglestageresection. Previously themajorityofthesepatientswould haverequiredtwostagesurgery(Hartmann’s procedureand reversalof Hartmann’s procedure).

Stentingofmalignantcolonicstricturesisaminimallyinvasiveendoscopicprocedurerequiring no incision. The procedure would take 30 – 90 minutes according to the application. Deployment ofthestentattheobstructedpartofthecolonisusuallyperformedinhospitals equipped withresources inmanagingbowelobstructions. Thus,facilitieswithappropriately trainedendoscopists,operatingtheatres,anaesthetistsandradiologyserviceswould benecessary. Theprocedureisundertakenbyacolorectalsurgeonorgastroenterologist appropriatelytrained inthisprocedure.Nursingstaffwithendoscopy training,radiographystaffandequipmentfor fluoroscopyalso wouldbenecessary.

Theproposedfeefortheinsertionofcolonic stentis$650asfor2010.Accordingtothe application,thisfeeincludesthefeeforcolonoscopytothepointofobstruction, passageofa guide-wireacrosstheobstructionunderfluoroscopyanddeploymentofacolonicstent.The technicaldifficultyofthisprocedureexceedsthatfordeployment ofanoesophagealorbiliary stent.Thereliefofobstructionisaccompaniedbyimmediateandoftendramaticpassageofstool whichcan beextremelyunpleasantfor theproceduralistand other teammembers.

Giventhat10%ofprocedureswillbeunsuccessful, aseparatefeemaybeappropriatewherea guide-wirecannotbepassedacrosstheobstruction.However,accordingtotheDepartment of HealthAndAgeing,agenericMBSitemno(30001) iscurrentlyavailabletocover failed surgical interventions,suchasfailedinsertionofcolonicstents,where50%oftheusualfeecouldbe paid.Theattempttopassaguide-wiremaytakeupto45minutesbeforeabandoningthe attempt.Thefeeforflexiblesigmoidoscopy(32084)doesnotadequatelyremuneratethisattempt or theadditionalresourcesrequiredtoperform thisprocedure.

Theaboveconclusions inrelationtodemandforcolonicstentsintheAustraliancontext, effectivenessoftheinterventionandhealthcareresourcesrequirements arebasedon unreferenced dataprovidedintheapplication.Clinicianinputhassupportedtheseassumptions and calculations;however,a systematicreviewof theliteraturewouldverifythesedata.

Table7showsthe resourcestobe consideredfor the economicanalysis. Notethat allcosts used shall be updatedaccordingto the time at whichthe economicmodellingisundertaken,using actualdata orindexationasavailable.

Table7: Listof resourcesto beconsideredin theeconomicanalysis(Tabletobecompletedduringtheassessment)

Providerof resource / Settingin which resourceis provided / Proportion ofpatients receiving resource / Numberof
unitsof resource per relevant time horizon
per patient
receiving resource / Disaggregatedunit cost($)
MBS / Safety nets* / Other govt budget / Private health insurer / Patient / Total cost
Resourcesprovided to identifyeligiblepopulation
‐ Colonoscopy
‐ Radiology
‐ Pathology
Resourcesprovidedtoperformthesurgery(MBSitems)
‐ Laparotomy
(30375) / 501.50
‐ Rectum,high anterior resection and antegrade
coloniclavage
(32024) / 1,312.90
‐ Hartmann’s procedures
(32033) / 1,450.30
‐ Totalabdominal colectomyand
ileostomy(32009) / 1,312.90
‐ Rectum,low restorative anterior resection
withextra peritoneal anastomosis(3202
5) / 1,756.15
‐ Rectum,ultra-low restorative resection(32026) / 1,891.20
‐ Resectionof large intestine(32003) / 1,037.95
Resourcesprovided inassociationwithperformingthesurgery
‐ Surgeon
‐ Assistantsurgeon*
‐ Anaesthetist
‐ Initiationof managementof
anaesthesia
(20840) / 114.30
‐ X to Yhours of anaesthesia(refer
to 23063or similar) / 114.30
‐ Nurses
‐ Hospital stay(eg.
10days)
‐ Radiology
Resourcesprovidedtodeliverbestsupportivecare
‐ Hospital stay
‐ Chemotherapy
‐ Radiotherapy
‐ Palliation
Resourcesprovided inassociationwithbestsupportivecare
‐ Nurses
Resourcesprovidedtodeliverproposedintervention
Providerof resource / Settingin which resourceis provided / Proportion ofpatients receiving resource / Numberof
unitsof resource per relevant time horizon
per patient
receiving resource / Disaggregatedunit cost($)
MBS / Safety nets* / Other govt budget / Private health insurer / Patient / Total cost
Staff
- Proceduralist
(Colorectalsurgeonor gastroenterologist)
- Anaesthetist
Initiationof
managementof anaesthesia(20810) / 76.20
1:26to 1:30hoursof
anaesthesia(23063) / 114.30
-Twonurses
-Radiographer
Disposalequipment
-Colonicstent / 2,500-
3,000
-Guidewire / 375
- Cannula/catheter / 75
-Dyefor injection/
Ultravistcontrast / 25
Other
-Stentingprocedure / 650
-Theatrefacilities
-Hospitalstay(eg.5
days)
Resourcesprovided inassociationwithproposed intervention
Staff
-Endoscopist
Prerequisite
equipment
-Imageintensifier
-Fluoroscopy
/Colonoscopy& Tower
*Expertclinicalopinion notedthattheAssistantSurgeonsfeeis usually1/5of theSurgeonsfee.

Proposed structure of economic evaluation

Table8: Summaryof extendedPICOto definequestionsforpublic funding thatassessmentwill investigate

PatientpopulationInterventionComparatorOutcomespreferred for assessment

Healthcare resourcesto be considered

1. Managementofpatients withobstruction,stricture orstenosisdueto unknowndiagnosis, medicallyfitfor surgery, for whomsingle-stage surgery(resection)isnot appropriateor not successful

Metallicstents*, particularlySEMS

Eitheras abridgeto surgery

Or as adefinitive procedure(thatisthe stentisusedasa palliative

intervention)

Inallcases,stent migration mayoccur,or re-stentingmaybe required

Othersurgery(e.g.– colostomyorHartmann’s resection)*

Primaryoutcome: QALY

Secondaryoutcomes: Mortality(egat 30days) Avoidanceof multi- stagesurgery

Temporaryor permanent reliefof obstruction

Technicalsuccess(stent insertion)

Re-stenting

All safetyand complications,including stentmigration.(adverse events)

ReferTable7.

2. Managementofpatients withobstruction,stricture orstenosisdueto unknowndiagnosis, medicallyunfitfor surgery

Bestsupportivecare*Primaryoutcome: QALY

Secondaryoutcomes: Mortality(egat 30days) Alsoallothersecondary outcomesaslistedabove

3. Managementofpatients withobstruction,stricture orstenosiscausedby confirmedcancer, medicallyfitfor surgery, for whomsingle-stage surgery(resection)isnot appropriateor not successful

Othersurgery(non- curative,e.g.colostomyor Hartmann’s resection)*

Primaryoutcome: QALY

Secondaryoutcomes: Mortality(egat 30days) Alsoallothersecondary outcomesaslistedabove

4. Managementfor patientswithobstruction, strictureor stenosis causedbyconfirmed

cancer,medicallyunfitfor surgery

Bestsupportivecare*Primaryoutcome: QALY

Secondaryoutcomes: Mortality(egat 30days) Alsoallothersecondary outcomesaslistedabove

*Patientsare alsolikelyto receiveongoingmedicalmanagement.Themedicalmanagementconsistsofchemotherapy,radiotherapy, palliationand/orcombinationofa fewmedicaltreatments.Accordingto expertclinicalopinion, thetypeand combinationofmedical managementreceiveddependsoneachpatient’sstatusand is individuallybased.