radiotherapy in head and neck

8/18/2019 Radiotherapy in head and neck

1/57

AFTERNOON


2/57

RADIOTHERAPY

Presenter :Dr. Narla susheel

III yr PG

Dept of OMFS

Sids


3/57

CONTENTS

• PHYSICAL NATURE OF RADIATION

• BIOLOGICAL ACTION

• TUMOR EFFECTS

• NORMAL TISSUE EFFECTS AND

TOLERANCE

• PRINCIPLES OF RADIOTHERAPY

• EXTERNAL BEAM THERAPY• RESULTS & METHODS TO IMPROVE EBT

• BRACHYTHERAPY

•

RADIATION SOURCES•


4/57

• THE TRETMENT !SING IONISING

RDITION THT INTER"TS #ITH

F$!IDS TO PROD!"E FREE IONS• T%PE: E$E"TROMGNETI"• RNGE : &' (e) * +, Me)• SO!R"E: - ray set or $INER

""E$RTOR &' /o0alt fro1 de/ay of

radio isotope


5/57

RDITION DOSGE 2 "ON" OF

RDITION EFFE"T 3!NTIT% OF≠ENERG%

• SI !nit of a0sor0ed dose is GR% 4Gy5• Gy 2 67oule 8 (9• Old unit 2 the rad• 6'' rads 2 6Gy


6/57

BIOLOGICAL ACTION


7/57


8/57


9/57

• Cells – onsng ra!aton – "reera!cals #ntercellular $ater%

• A!&acent large 'olecules (

!enaturaton• I" DNA Da'age – cell ) 'toss )• I" cell atte'pts to !*!e – cell !eath

ensue – MITOTIC DEATH


10/57

T!MOR EFFE"TS

• Rate o" cell prol"eraton + nter*al,-$

rra!aton

an! cell !eathG*en Dose sterlsng all the tu'orcells !epen!s on . "actors/

01RADIOSENSITI2IT341O)3GENATION 5.1T6MOR SI7E


11/57

• Ra!osenst*t8/ 9ologcal nherentpropert8

•Depen!s on the a,lt8 o" the cell torepar DNA !a'age1

•

O:8genaton/ A't o" O4 conc ; t'eo" ra!aton + Free ra!cal to causecell !eath

• Tu'or S


12/57

NORMA> TISS6E EFFECTSAND TO>ERANCE

• MITOTIC DEATH – nor'al tssue – s!ee?ect

• Acute reactons # Heal co'pletel8%(

Mucosa (04 !a8s@ s=n – 40 !a8s –'an"est ra!aton changes

• 2ascular en!othelal !a'age –

.'onths to se*eral 8ears ( late!a'age an! rre*ers,le1


13/57


14/57

PRINCIP>ES OFRADIOTHERAP3

• Fun!a'ental 'etho!s o"ra!otherap8/01 Teletherap8 or E:ternal ,ea'

Ra!aton/e:ternal source through a

'achne1

41 9rach8therap8( source s $thn orn

close

pro:'t8 –


15/57

E)TERNA> 9EAM THERAP3

• Most $!el8 use!• A,sorpton energ8 o" photons an!0- $a*elength1

• Ortho*oltage )( ra8 'achnes – .=* – lo$ penetraton – 'a: !ose tos=n sur"ace – s=n reactons

• A!! !sa!*antage ( 2er8 hgha,sorpton 'aterals $th hgh ato'cnu',ers – eg calcu' (

osteora!onecross


16/57

• Ne$er a!*ances –• TE>ECO9A>T MACHINES ( ra!aton(0 Me2

• >INEAR ACCE>ARATORS – )(Ra8s –Me2

• AD2ANTAGES/ More penetraton !epth

; se*eral 'll'eters ,elo$ s=nsur"ace

• A,sorpton n 'atter s less

!epen!ent on ato'c nu',er so


17/57

Super *oltage ra!aton

• 4 or 'ore ,ea's o" ra!atoncon*ergng on tu'or *olu'e arepro&ecte!

• >atter s rra!ate! ho'ogenousl8 tothe reure! !ose $hle the

negh,orng tssues through $hch tpasses rece*e lo$er !ose1


18/57

Fractonate! E9T

•TOT$ DOSE is diided in to anu10er of s1aller doses

deliered oer a period of seeral;ee


19/57

• Nor'al cells – regenerat*e capact8to repar !na !a'age

• Tu'or response ,8 reo:8genaton

o" h8po:c cells• Ol!er ra!aton sche'es – 0( "ractons ; 04 $ee=s

• Coutar! – 0ce !al8 ; J to $ee=s


20/57

• Oral an! sal*ar8 glan! oncolog8 (s'all treat'ent *olu'es – . c'.or less ;K $ee=s

• JJ G8 ; 4 "ractons ; $ee=s "orra!cal treat'ents

• To lessen the e?ects l=e 'ucosts@

longer treat'ent t'e $th a!euatenutrton suppl8 to the pt n 'eant'e s calle! altere! or

uncon*entonal ra!aton•


21/57

Metho!s to 'pro*e resultso" E9T

• 4 poss,le e:plotatons ,-$ tu'orcells na! nor'al cells are the / –01 o:8gen e?ect

–41 cell prol"eraton =netcsO)3GEN EFFECT – as "ractonate! therap8contnues the o:8genaton o" tu'or cellsoccur $here aggre*aton o" the tu'or s

relat*e to occur1 To o*erco'e the O4 e?ect H8per,arc O4@neutron therap8 an! h8po:c cell

ra!osenstsng !rugs


22/57

H3PER9ARIC O4 THERAP3

• A' s to suppl8 the ra!o resstanth8po:c tu'or $th 'ore O4 at rase!pressure

• Bth pure O4 at . at' – =lls onl810L o" h8po:c cells1

• E?ect*eness o" h8per,arc O4

therap8 0- s


23/57

H3PO)IC CE>> SENSITISINGAGENTS

• O+ * RDIOSENSITISING "TION *E$"TRON FFINIT%

• NE#ER E$E"TRON FFINIT% "OMP!NDS

SIMI$R TO O+ * RDIO?IO$OGI"$PROPERTIES THT RE NON * TO-I-

ND ESI$% DIFF!S?$E 4I)5 RE

ST!DIED• $$ ?E$ONGED TO NITROIMID@O$E

FMI$% * NE!ROTO-I" A SFE DOSES

RE INS!FFI"IENT FOR THE THERP%• NIMOR@O$E


24/57

NE6TRON THERAP3

• Here the t8pe o" ra!aton s less!epen!ant on O4 presence "or thecell =llng e?ect1

• Intro!ucton o" FAST NE6RONS• Dsa!*antages / ,ross an! necross

• As late respon!ng nor'al tssues aacu'alte'ore ra!aton !a'age n ths t8pe $henco'pare! to Electro'agnetc ra!atonn*ol*ng nor'al tssue co'plcatons1


25/57

A>TERED FRACTIONATION

• Increase n nu',er o" "ractons an!re!ucton n the s


26/57

• Tpot – rate o" cell turno*er – t'eta=en ,8 the tu'our to !ou,le thecell *ol " none $ere she!@ !e! an!

!?erentate!•ESTIMTION * throu9h 0iopsy• In7 * ?ROMODEO-% !RIDINE *

la0els /ell in S phase.• Tpot ( scc – .(J !a8s


27/57

• Rate o" repopulaton o" the tu'orncreases !urng a course o"ra!otherap81

• ACCE>ARATION – shortenng thetreat'ent t'e to o*erco'e thee?ect o" repopulaton1

• To re!uce the FRACTION SI7E ACCE>ARATION Q E>EMENT OFH3PERFRACTIONATION


28/57

CHART

• CONTINO6S H3PERFRACTIONATEDACC>EARATED RADIATION THERAP3

• ( NEB accelarate! h8er"ractonate!

reg'es• Intro!uce! ,8 DISCHE ANDSA6NDERS

• Total !ose o" J G8 – splt to ."ractons o" 01J G8 ; 04 !a8s 1


29/57

9RACH3THERAP3•Source o" ra!aton s place! *er8 close tothe tu'or ,e! ,8 4 'etho!s –01 sur"ace 'oul!s –41 ntersttal 'plants

–Prncple/ Depen!s on the >AB OF IN2ERSES6ARES

– 0

INTENSIT3 OF DOASGE OF RADIATION

(((((((((((((((((


30/57

INTERSTITIA> T3PE

• sol! sources – 'plante! !rectl8nto tu'or – hgh !ose o" ra!aton –rap! "allo? – !el*ers lo$ to

surroun!ng nor'al tssues1• Here ho'ogenous !el*er8 o" $hole*s,le an! palpa,le area o" tu'or

$th atleast 0c' sa"et8 'argn se:pose!

• So applca,le to onl8 so"t tssue1


31/57

Ra!aton sources

• 4 t8pes o" ra!oact*e 'aterals areuse!

• 01 re'o*a,le•

41 per'anentl8 'planta,le –short l*e! an! arerea!l8 !eca8e! to a neglg,le act*t8

GO>D – 0 SEEDS

Del*ere! $th a specal G6N

Accuarte an! un"or' !str,utons not poss,le

Rarel8 use!


32/57

• REMO2A9>E RADIATION SO6RCES1• Earl8 !a8s – ra!u' $as onl8 'ateraluse! enclosng n platnu' nee!les o"

41J '' !a'eter an! 01J ( c' nlength

• ) Ra!u' ) – artcal sotopes – sa"er

han!ellng


33/57

• CAESI6M – 0.• Sa'e as the ra!u'

!el*er8 nee!les

Dsa!*antages – operator e:posure Thc= neee!les – trau'natc an!

unco'"orta,le


34/57

Irr!u' ( 04

• Most popularl8 use!to!a8

• Isotope o" choce "or

oral carcno'as• A*al,le – "or' o"thn $re

•Slotte! gu!e nee!lesor plastc tu,ng areuse!


35/57


36/57

Plastc tu,ng technue

• Fner rra!u' $re o" 1. ''!a'eter s use! *a plastc tu,ng

• Tu,es – straght hollo$ gu!e nee!les

– s=n to oral ca*t8• True a"ter loa!ng• Due to $hch the ra!aton e:posure

to sta? an! operator s co'pletel8a*o!e!1

• 6se! n areas o" posteror 0-. r! o"

the tongue an! n chee=


37/57

Dosage

• 9rach8therap8 alone – J( G8 splt1. – 1J G8 "ractons - hr ; J1J – !a8s1

• E:ternal ra!otherap8 Q,rach8therap8

0st e:ternal ,ea' – G8 ;

$ee=s IMP>ANT – .J( G8

Total t'e shoul! ne*er e:ten! ,e8ong

$ee=s


38/57

Pallat*e ra!otherap8

• A' / rel*e s8'pto's o" the !sease• No atte'pt to cure s 'a!e• Approprate "or pts $th ncura,le an!

shor l"e e:pectanc8 pts• Rel*es s8'pto's l=e ,lee!ngpressure pan or o,structon

•6se! 'ostl8 n ,one@,ran or s=n – 4G8 ; J !a8s1

• Not a!*sa,le n oral carcno'as

o' ne ra ot erap8 an


39/57

o' ne ra ot erap8 ansurger8

• Bhen ra!cal ra!otherap8 "allslea*ng a res!ual or recuurence thensurgcal cure s poss,le

• Surger8 per"or'e! a"ter "ale! ra!cal'o!e s =no$n as SA>2AGE S6RGER3

• Co'plcatons / !ela8e! $oun!

healng stula "or'aton $oun! ,rea=!o$n an! carot! arter8 rupture

• Co'plcaton rate s lo$ $hen surger8

per"or'e! . 'onths a"ter


40/57

Pre operat*e ra!otherap8

• A' / ncrease the chance o" thesurgcal cure ,8 recee!ng the gro$thalong the ,or!ers an! the perpher8

o" the tu'or1• 9ase! on 4 !?erent concepts• >o$ !ose technue/ Sgncant lo$

!ose s a!'nster! ''e!atel8,e"ore e:cson contnung "or "e$!a8s n "e$ large "racton an!

operatng ''e!atel8 ,e"ore an8


41/57

• Hgh !ose technue/• Con*entonal !al8 "ractons o*er (J$ee=s ; – J G8

• Results n nor'al tssue reactons an!h8pere'a an! surger8 s !ela8e! "or"urther . – $ee=s1


42/57

Post operat*e ra!o therap8

• >ess e?ect*e than pre operat*e• A"ter surger8 cells are poorl8*ascularse! an! relat*el8

ra!oresstant1• Post op ra!otherap8 – $thn $ee=s; J G8 – 4J "ractons are !el*ere!1

•

A"ter $ee=s – !ose o" G8 – ."ractons


43/57

S!e e?ects

• Classe! as acute an! late e?ects

• AC6TE EFFECTS –M6COSITIS/ Occurs !ue to 'totc cell

!eath n epthelal lnng –Cell c8cle t'e s !8as an! ,asla la8er s

4( cells thc= –Ra!aton changes are seen a"ter 04 !a8s –Intal8 erthe's@ pathc8 ,rnous e:u!ate –Hgh !ose ( ulceraton $th thc= ,rous

'e',rane o*er the !enu!e! sur"ace1 –


44/57

• SUIN REACTION/ –Cell turno*er s lo$ –.r! $ee= – er8the'a !e*elops 5 prgress

to !r8 an! 'ost !esua'aton –No$ super*oltage ,ea's are use! "or

sur"ace sparng e?ect1


45/57

• alopeca s seen• >oss o" taste sensaton/ 'echans'un=no$n

G8 pro!uces loss o" 0L o" tastecells1 Reco*er8 s "or 'onths1

)EROSTOMIA/ loss o" secretor8 cellsoccurs

Acn are ncapa,le o" reco*erng an!


46/57

• 4 G8 – In a!ults can causeper'anent cessaton to sal*ar8 o$– !'nshes ; J !a8s 5 a"ter J

$ee=s o$ – L an! ne*er reco*ers1• Nasoph8ar8n: ra!otherap8 –!estro8s ,-l parot!s an! – per'anent

:erosto'a1• Salogogues l=e prlocarpne areuse!

•

Artcal sal*as are no$ a*ala,le1


47/57

• In"ecton/ ncrease! 'ucostts an!:erosto'a 'a8 lea! tosupern"ecton $th can!!a1

• Increase! pan an! er8 er8the'a• Dscrete $hte plaues o" thrush• Chlorhe:!ne 14L !lute! to 10L s

reco''en!e! or 'cona


48/57

>ate e?ects

• Ische'a an! ,ross• So"t tssue necross – *arng !egreeso" atroph8@ telangctesa@ !r8ness an!

"raglt8 o" the 'ucosa• 9one necross – osteora!onecross


49/57

MAR) – H8po:c h8po cellular an!

h o *ascular theor


50/57


51/57

rotoco or pts $ o reu re


52/57

rotoco or pts $ o reu re!ental e:tractons a"ter

ra!otherap8

Dental care o" patents


53/57

Dental care o" patentsrece*ng ra!otherap8

• Teeth not n rrar!ate! *olu'e• Mouth $ashes – !lute! sol o" chlorhe:!ne

gluconate Oral rnse "or 0 'n $th J'l o" sol n 0 'l o"

$ater

• Topcal our!e applcatons / custo' ,ultcarrers are 'a!e

pt s g*en $th *scose gel o" 0L so!u' our!en a

suee


54/57

• Acr8lc splnts/ coVn a!*ocate!co*erng the teeth $th splnts !urngan! post op "or 4 8rs

• Sal*a su,sttute/ the8 help n =eepngthe 'outh 'ost@ rase the PH1 –Shannon "oun! that the rra!ate pts

sal*a $oul! pro!uce re'neralsaton o"ena'el n e:tracte! teeth n*tro pro*!ecalcu' phosphate an! our!e


55/57

• Teeth $th n the rra!ate! *olu'e• Teeth to ,e e:tracte! are – non( *taltooth nee! o" RCt or ela,rat*e

restorat*e technues or assocate!$th act*e pero!ontal !sease

• E:tractons shoul! ,e per"or'e!

atrau'atcall8 an! gu's suture! topro'ote rap! healng

• I" e:tarcton s necessar8 n hgh !oserra!ate! *olu'e then atru'atc


56/57


57/57

HAN 6

radiotherapy in head and neck

Documents