Title:GammakniferadiosurgeryOctober2000

Agency:Medicare Services Advisory Committee (MSAC) Commonwealth Department of Health and Ageing GPOBox9848CanberraACT2601Australia

Reference:MSAC application 1028. AssessmentreportISSN1443-7120

Aim:Toassessthesafetyandeffectivenessoftheserviceandunderwhatcircumstancespublic funding should be supported for the service in relation to the treatment of arteriovenousmalformation(AVM),cerebralmetastasesandacousticneuroma.

Conclusionsandresults

Methodologicallimitationsofstudiesandpatientheterogeneityprecludecomprehensive assessmentofthesafetyandeffectivenessofgammakniferadiosurgeryrelativetoalternative treatment.

Indication / AVM / Cerebralmetastases / Acousticneuroma
Safety / Thereis insufficientinformationtoassess therelativesafetyofgammaknifeorlinear accelerator(LINAC)radiosurgeryand microsurgery. Studiescontain methodologicallimitations,patient selectionbiasesandinconsistentadverse eventdefinitions. Permanentneurological complicationsoccurredin1-10%of radiosurgerypatientsandupto 15%of microsurgerypatients(5%forsmall accessiblelesions). / Theonlyusefuldataisfrom caseseries:10%incidenceof radiationnecrosis(1%fatal),
20%incidenceofacute radiationinducedodema20%. Onestudysuggests radiosurgeryandwholebrain radiotherapy(WBRT)incur similarcomplicationrates. / Complicationrates aresimilarfor radiosurgeryand microsurgery:
facialnerve problems(20%) andhearing preservation(30-
90%). Fewstudies reportedother
complications.
Effectiveness / TwoyearAVMobliterationratesare26-
35%forgammakniferadiosurgeryand44-
68%forLINACradiosurgeryasa percentageofpatientseligiblefor angiography. Thesearelikelytobe overestimatesas onlysomeof thepatients eligibleforangiographyundertookthe procedureandpatientfollowupwas inadequate. Thiscomparesto85-100% obliterationratesformicrosurgery(higher forsmallaccessiblelesions). / Onerandomisedtrial(and somesupportivecaseseries data)suggestthatradiosurgery in additionto WBRTshowsno survivalbenefit,butmay provideslightlyimprovedlocal controlwhencomparedjustto WBRT. / Microsurgical excisionratesare closeto100%and tumourcontrol rateswith radiosurgeryare measuredat80-
100%.
Cost effectiveness / Gammaknifewas1.7-2.9timesmoreexpensivethanLINACradiosurgery.Uncertaintiesasto safetyandeffectivenessprecludeaneconomicevaluationofgammaknifeandcomparators. / As per column 1 / As per column 1

Recommendation

Publicfundingshouldnotbesupportedforgammakniferadiosurgeryatthistime.

Method

MSACconductedasystematicreviewofmedicalliteratureusingMedline,PreMedline,EmBase, the Cochrane Library, ISTAHC, Current Contends, HealthSTAR and NHS databases: (DARE, EED,HTA)fromcommencementuntilMarch2000.Internetsitesofcertainhealthtechnology assessmentgroupswerealsoincluded.TheAANSandCNSMeetingAbstractArchiveandthe table of contents for Radiosurgery werealsosearched.