EBS Presentation - Salam Tooza

1. EBS Presentation
09/09/2021
Salam Tooza
Radiotherapyornotafterresectionofopticnervepilocyticastrocytoma

2. Clinical Case
- A69year-oldmalecomplainedofworseningofrightvisuallossover7months
- BrainMRIshowedextra-axialmasslocatedinsuperioraspectofthepituitarygland
- Underwentresectionofskullbasetumour
- Histopathology:PilocyticastrocytomaWHOGrade1

3. Introduction about Pilocytic astrocytoma
• pilocyticastrocytoma(PCA),previouslyknownascystic
cerebellar astrocytomaorjuvenilepilocyticastrocytoma,was
firstdescribedin1931byHarveyCushing,basedonacaseseries
ofcerebellar astrocytomas;thoughheneverusedtheseterms
butratherdescribedaspongioblastoma
• Theyarelow-grade,andusuallywell-circumscribed tumours,
whichtendtooccurinyoungpatients.BytheWorldHealth
Organization(WHO)classificationofcentralnervoussystem
tumours,theyareconsideredgradeIgliomasandhave
relativelygoodprognosis.

4. Introduction Pilocytic astrocytoma
• PCAmostoftenpresentsintheseconddecadeoflife,with75%occurringbeforetheageof20years.
• Thereisastrongassociationbetweenneurofibromatosistype1(NF1)andPCA,withupto20%ofpatientswithNF1developingaPCAmostcommonlyin
theopticpathway
• BRAFgenealterationsandMAPKsignallingpathwayalterationshavebeenfoundinthemajorityofPCAs
• PCAtendstooccurclosetothemidline,although,inanadult,itcanbemorelateralwithinthecerebellum.PCAscanoccuranywherewithin
theneuroaxis:[16]
1. Cerebellum-42%to60%,
2. Opticgliomas&hypothalamicgliomas-9%to30%ThemostcommonsiteforPCArelatedtoNF1[5]
3. Brainstem-9%[5][19]
4. Spinalcord-2%
5. Cerebralhemispheres(youngadults

5. Searchable question
PICO
• Population :Allpatientwhohadresectionofopticnervepilocyticastrocytoma
• Intervention:treatedwithRadiotherapy
• Control :no radiotherapy
• Outcome : survivalrate
• Radiotherapyornotafterresectionofopticnervepilocyticastrocytoma?

6. Search terms
• Astrocytoma/
• pilocytic.tw.
• pilocyticastrocytoma.tw.
• radiotherapy/orcranialirradiation/orradiotherapy,adjuvant/orradiotherapy,high-energy/ or
radiotherap*.tw.
• optic.tw.

7. Search Criteria
• Inclusioncriteria
Allpatientwithpilocyticastrocytoma
• exclusioncriteria
papersbefore2016

8. •Prisma
• Medline58
• Pubmed14
• Scopus 5
• others2
• Abstractreviewed10
• Articlereviewed3
• Mostrelevant1

11. Summary of paper

16. • Mostrelevantarticle
• PublishedinJournalofneuroscience
• CLINICALSTUDY|VOLUME81,P340-345,NOVEMBER01,2020
• 451patientidentifiedinthearticle
• Themeanageofthepatientwas36.8yearsold,andthemajorityofpatients(83.4%)didnotreceiveRTfollowingsubtotalPCA
resection.Overallmediansurvivalwas>93.8months.
• Comparewithpatientswhowereolderatdiagnosis(hazardratio[HR]=1.04,95%confidenceinterval[CI]=1.02-1.06,p<0.01),
black(HR=2.35,CI=1.05-5.23,p=0.037),orreceivedradiotherapyduringtheirinitialtreatment(HR=3.77,CI=1.77-8.03,p<
0.01)hadasignificantlyhigherriskofdeathfollowingsubtotalPCAresection.

19. Conclusion
.Icouldn’tfindapaperwhichclearlycorrelateopticnervepilocyticastrocytomaandradiationoutcomebut
therewasfewarticleswhichshowingeffectofradiotherapyinpatientwithpilocyticastrocytomaregardless the
locationofthelesion
.Radiotherapyforpatientwithpilocyticastrocytomaassociatedwith significanthighriskofdeathfollowing
subtotalpilocyticastrocytomaresection.

20. •Thank you