Radiation Therapy Radiation Therapy of Oral Cancersof Oral Cancers

Dr. V. Lokesh M.DDr. V. Lokesh M.DProfessor & Head of UnitProfessor & Head of UnitDepartment of Radiation Department of Radiation

Oncology, Kidwai Memorial Oncology, Kidwai Memorial Institute of Oncology, BangaloreInstitute of Oncology, Bangalore

Radiation therapy is the art of using Radiation therapy is the art of using ionising radiation to destroy ionising radiation to destroy malignant tumours while being able malignant tumours while being able to minimise damage to normal to minimise damage to normal tissue.tissue.

IntroductionIntroduction Basics of Radiation TherapyBasics of Radiation Therapy

Ionizing Radiation – X / Ionizing Radiation – X / γγ Rays Rays Interaction of Radiation with matterInteraction of Radiation with matter

Transmission

Attenuation

Scatter Absorption

Rad / Grey / cGy

Cancer Cell & Ionizing Cancer Cell & Ionizing RadiationRadiation DNADNA is primary target is primary target

Double Strand breaks – Primary Double Strand breaks – Primary requisiterequisite

Reproductive Cell DeathReproductive Cell Death

RT is a Double Edge RT is a Double Edge SwordSword

↑ ↑ RT RT DoseDose

↓ ↓ RT DoseRT Dose

↑ ↑ T – ControlT – Control ↓ ↓ T – ControlT – Control

↑ ↑ Normal Normal Tissue Tissue ToxicititesToxicitites

↓ ↓ Normal Normal Tissue Tissue ToxicititesToxicitites

TeletherapyTeletherapy TelecobaltTelecobalt Linear AcceleratorLinear Accelerator

Simple TeletherapySimple Teletherapy SRS/SRTSRS/SRT 3DCRT3DCRT IMRTIMRT IGRTIGRT Rapid ArcRapid Arc True BeamTrue Beam

Gamma KnifeGamma Knife TomotherapyTomotherapy Cyber KnifeCyber Knife

BrachytherapyBrachytherapy IntracavitoryIntracavitory InterstitalInterstital MouldMould

Pre Loaded / Pre Loaded / AfterloadingAfterloading

Manual / RemoteManual / Remote LDR / HDR LDR / HDR

Kilovoltage X-Ray 1920Kilovoltage X-Ray 1920

Telecobalt 1970sTelecobalt 1970s

Linear AcceleratorLinear Accelerator 3DCRT 3DCRT IMRTIMRT

True BeamTrue Beam

BrachytherapyBrachytherapy

RT in Oral CancerRT in Oral Cancer

Management:Management: Treatment OutcomeTreatment Outcome CosmesisCosmesis Organ Preservation & FunctionOrgan Preservation & Function AgeAge Quality of lifeQuality of life

RTRT Radical RTRadical RT

RT:RT: Conventional (7-8 weeks)Conventional (7-8 weeks) Hyperfractionation (5-6 weeks)Hyperfractionation (5-6 weeks) Hypofractionation (1-2 Gap 1-2 weeks)Hypofractionation (1-2 Gap 1-2 weeks)

Pre Operative RT Pre Operative RT (2-5 weeks)(2-5 weeks)

Post Operative RT Post Operative RT (5-7 weeks)(5-7 weeks)

Palliative RTPalliative RT Short Course Short Course (1-2 weeks)(1-2 weeks)

Saturation Technique Saturation Technique (1-2 weeks gap 3-4 weks)(1-2 weeks gap 3-4 weks)

RT CombinationsRT Combinations RT aloneRT alone

Photons alonePhotons alone Photons + ElectronsPhotons + Electrons Recent adv - Photons + Particle Recent adv - Photons + Particle

(Protons/Neutorns/C ions)(Protons/Neutorns/C ions) RT RT ++ Radiation Sensitizers (CT drugs / BRM / Radiation Sensitizers (CT drugs / BRM /

CT+BRM)CT+BRM) RT RT ++ Radiation Protectors (Amifostine) Radiation Protectors (Amifostine)

RT RT ++ Brachytherapy Brachytherapy Brachytherapy aloneBrachytherapy alone

Brachy typeBrachy type Single palne implantSingle palne implant Duble plane implantDuble plane implant Volume implantsVolume implants

Indications for RT in Indications for RT in Oral CaOral Ca

Radical RTRadical RT T1, T2, T3, T4a T1, T2, T3, T4a

Unresectable (Altered Fractionation HF/CB or RT + Unresectable (Altered Fractionation HF/CB or RT + Radiation Sensitizer)Radiation Sensitizer)

elderly, frail, comorbid conditionselderly, frail, comorbid conditions refusal for surgeryrefusal for surgery prohibitive morbidity due to surgeryprohibitive morbidity due to surgery

Pre OP RT : Pre OP RT : potentially inoperablepotentially inoperable Post OP RT : Post OP RT : (RT + Radiation Sensitizer)(RT + Radiation Sensitizer)

pT3/4pT3/4 Close & +ve marginClose & +ve margin Multiple nodesMultiple nodes Perineural invasionPerineural invasion Lympho vascular space invasionLympho vascular space invasion Extra Capsular extensionExtra Capsular extension Level IV – V nodesLevel IV – V nodes

RADIOTHERAPY DOSERADIOTHERAPY DOSE

1. External :1. External :

a. Alone : 7000 cGy to 7600 cGy /6-8 wks. a. Alone : 7000 cGy to 7600 cGy /6-8 wks.

(microscopic - 4600 - 5000 cGy)(microscopic - 4600 - 5000 cGy)

b. Pre-op. : 46-50 Gy/ 4 1/2 - 5 1/2 wks.b. Pre-op. : 46-50 Gy/ 4 1/2 - 5 1/2 wks.

c. Post-op.: 60-66 Gy/ 6-7 wks.c. Post-op.: 60-66 Gy/ 6-7 wks.

2. Brachytherapy :2. Brachytherapy :

a. Alone : 6000 - 7000 cGy in 6 to 7 days.a. Alone : 6000 - 7000 cGy in 6 to 7 days.

b. External + Brachytherapyb. External + Brachytherapy

Ext : 46-50 Gy in 4 1/2 - 5 1/2 wks. Ext : 46-50 Gy in 4 1/2 - 5 1/2 wks. ++

Brachy : 2000-3000 cGy in 2-3 days Brachy : 2000-3000 cGy in 2-3 days

pre- radiotherapy Dental pre- radiotherapy Dental ProphylaxisProphylaxis

ExtractionExtraction Caries (non-restorable)Caries (non-restorable) Active periapical disease (symptomatic teeth)Active periapical disease (symptomatic teeth) Moderate to severe periodontal diseaseModerate to severe periodontal disease Lack of opposing teeth, compromised hygieneLack of opposing teeth, compromised hygiene Partial impaction or incomplete eruptionPartial impaction or incomplete eruption Extensive periapical lesions (if not chronic or Extensive periapical lesions (if not chronic or

well localized)well localized)

Start RT after 10 – 14 daysStart RT after 10 – 14 days

RT TechniquesRT Techniques

Simple TeleSimple Tele 3DCRT / IMRT3DCRT / IMRT

Mould RoomMould Room

Patient postioning : Patient postioning : SupineSupine Neck – Extension / hyperflexionNeck – Extension / hyperflexion

Immobilzation devisesImmobilzation devises Head restHead rest Bite blockBite block Tongue depressorTongue depressor ThermoplasticsThermoplastics

SimulationSimulation

Simulator X-Ray MachineSimulator X-Ray Machine CT ScannerCT Scanner

An Isocentric Mounted Simulator X An Isocentric Mounted Simulator X _Ray machine is used to simualte_Ray machine is used to simualte

Fields and Position before treatment Fields and Position before treatment fields will be marked on a patientfields will be marked on a patient

Conventional 2D Conventional 2D PlanningPlanning

3D CRT / IMRT3D CRT / IMRT

Laser setupLaser setup

Virtual SimulationVirtual Simulation

CT-based virtual simulation CT-based virtual simulation use a full 3D image datasetuse a full 3D image dataset software toolssoftware tools external laser system for markingexternal laser system for marking

radiation therapy targetsradiation therapy targets

PLANNING : ECLIPSE / PLANNING : ECLIPSE / HELIOSHELIOS

CONTOURINGCONTOURING

FusionFusion

MRIMRI PET CTPET CT AngioAngio othersothers

IMRT: FIELDIMRT: FIELD

IMRT : PLANIMRT : PLAN

Neck node CoverageNeck node Coverage

Acute side effectsAcute side effects

Skin – Hyper pigmentation, Dry and Skin – Hyper pigmentation, Dry and moist desqumationmoist desqumation

Mucosa- Mucositis G2/3Mucosa- Mucositis G2/3 Pharynx – Odynophagia / dysphagiaPharynx – Odynophagia / dysphagia Larynx – hoarseness of voiceLarynx – hoarseness of voice Salivary - XerostomiaSalivary - Xerostomia

5 YR SURVIVAL5 YR SURVIVALSTAGE 1STAGE 1 STAGE STAGE

IIIISTAGEIIISTAGEIII STAGEIVSTAGEIV T 3/4T 3/4

LipLip 90%90% <60-30%<60-30% 30%30%

Anterior TongueAnterior Tongue 69%69% 41%41% 25%25%

S+R - 35%S+R - 35%15%15% 33-60%33-60%

Buccal MucosaBuccal Mucosa 77%77% 65%65% 27%27% 18%18% 33-67%33-67%

Floor of the Floor of the MouthMouth

97%97% 72%72% 51%51% 20%20% 33-67%33-67%

Lower GingivaLower Gingiva

Retromolar Retromolar TrigoneTrigone

70%70% 50-30%50-30% 30%30% 30-50%30-50%

Upper GingivaUpper Gingiva

Hard PalateHard Palate 75%75% 46%46% 36%36% 115115

During radiotherapyDuring radiotherapy

Maintenance of good oral hygiene Maintenance of good oral hygiene Brushing 2 to 4 times daily with soft-Brushing 2 to 4 times daily with soft-bristled brush; flossing dailybristled brush; flossing daily

Daily topical fluoride Custom trays, Daily topical fluoride Custom trays, brush-on prescription-strength fluoridebrush-on prescription-strength fluoride

Frequent saline rinsesFrequent saline rinses Lip moisturizer (non-petroleum based)Lip moisturizer (non-petroleum based) Passive jaw-opening exercises to Passive jaw-opening exercises to

reduce trismusreduce trismus

After radiotherapyAfter radiotherapy

Complete dental work that was Complete dental work that was deferred during radiotherapydeferred during radiotherapy

Maintain integrity of teeth Especially Maintain integrity of teeth Especially those in radiation fieldsthose in radiation fields

Frequent follow-upFrequent follow-up

Follow-upFollow-up

Clinical examination of head and neck mucosa Clinical examination of head and neck mucosa (including fiberoptic ) and neck palpation / (including fiberoptic ) and neck palpation / performance status / nutritional assessmentperformance status / nutritional assessment

every 2 months (first 2 years),every 2 months (first 2 years), every 6 months (years 3-5),every 6 months (years 3-5), once a year (> 5 year)once a year (> 5 year) Dental examination and orthopantomogram every 6 Dental examination and orthopantomogram every 6

monthsmonths Chest X-ray every yearChest X-ray every year Chest spiral CT every yearChest spiral CT every year Laboratory tests: TSH every year (if Laboratory tests: TSH every year (if

Radiotherapydelivered)Radiotherapydelivered) Evolution of late toxicity (EORTC/RTOG) scaleEvolution of late toxicity (EORTC/RTOG) scale

Salvage treatment for Salvage treatment for recurrent diseaserecurrent disease

Lip, mobile tongue, floor of mouth:Lip, mobile tongue, floor of mouth: T1 N0 :T1 N0 :

BrachytherapyBrachytherapy SurgerySurgery

Any other T, any other NAny other T, any other N Surgery + radical ND ± post-operative RxTh if not Surgery + radical ND ± post-operative RxTh if not

previously deliveredpreviously delivered RxThRxTh

Palliative carePalliative care Metastasis :Metastasis :

Chemotherapy + best supportive careChemotherapy + best supportive care

Thanking youThanking you