igrt srt for lung cancer

ImageImage--Guided and Guided and Stereotactic Radiotherapy Stereotactic Radiotherapy

(IGRT/SRT) for Lung (IGRT/SRT) for Lung CancerCancer

Gregory S. Sibley, M.D.Gregory S. Sibley, M.D.November 17, 2008November 17, 2008

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Evolution of TechnologyEvolution of TechnologyIntensityIntensity--Modulated Radiotherapy (IMRT)Modulated Radiotherapy (IMRT)ImageImage--Guided Radiotherapy (IGRT)Guided Radiotherapy (IGRT)Stereotactic Radiotherapy (SRT)Stereotactic Radiotherapy (SRT)TomotherapyTomotherapySpecific CaseSpecific Case

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Evolution of TechnologyEvolution of TechnologyIntensityIntensity--Modulated Radiotherapy (IMRT)Modulated Radiotherapy (IMRT)ImageImage--Guided Radiotherapy (IGRT)Guided Radiotherapy (IGRT)Stereotactic Radiotherapy (SRT)Stereotactic Radiotherapy (SRT)Specific Disease SitesSpecific Disease SitesTomotherapyTomotherapy

Evolution of TechnologyEvolution of Technology

19701970’’s: Cobalts: Cobalt--60, treatment guided by 60, treatment guided by surgical anatomy and plain radiographs. Doses surgical anatomy and plain radiographs. Doses calculated from depthcalculated from depth--dose charts.dose charts.19801980’’s: Crosss: Cross--sectional imaging (CT) sectional imaging (CT) available to guide treatment delivery.available to guide treatment delivery.19901990--1995: 1995: ““HomeHome--growngrown”” 3D conformal 3D conformal radiotherapy planning systems appearing radiotherapy planning systems appearing allowing Beamallowing Beam’’s Eye Views Eye View

Evolution of TechnologyEvolution of Technology19951995--2000: Commercial 3D CRT planning 2000: Commercial 3D CRT planning systems available with routine adoption by systems available with routine adoption by most centers.most centers.1998: Sibley acquires 3D planning system.1998: Sibley acquires 3D planning system.19991999--2003: Patients routinely planned and 2003: Patients routinely planned and treated with 3D CRT and 3D dose calculation. treated with 3D CRT and 3D dose calculation. 2002: Sibley Cancer Center opens 11/02 with 2002: Sibley Cancer Center opens 11/02 with statestate--ofof--thethe--art digitally controlled linear art digitally controlled linear accelerators.accelerators.

ExternalExternal--Beam RadiotherapyBeam RadiotherapyPhoton energy 6Photon energy 6--23 MV23 MVFields collimated by Fields collimated by internal jawsinternal jawsFields shaped by internal Fields shaped by internal leaves (leaves (MLCMLC’’ss))Digital information transferDigital information transfer

Evolution of TechnologyEvolution of Technology

2003: 5/03 first patient treated with Intensity2003: 5/03 first patient treated with Intensity--Modulated Radiotherapy (IMRT)Modulated Radiotherapy (IMRT)2004: CT scanner/simulator installed in Cancer 2004: CT scanner/simulator installed in Cancer CenterCenter2006: Gold 2006: Gold fiducialfiducial markers implanted markers implanted routinely for prostate cancer for Imageroutinely for prostate cancer for Image--Guided Guided Radiotherapy (IGRT)Radiotherapy (IGRT)2008: Tomotherapy with Stereotactic 2008: Tomotherapy with Stereotactic Radiotherapy capability (SRT)Radiotherapy capability (SRT)

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IntensityIntensity--Modulated RT Modulated RT (IMRT)(IMRT)

Requires exacting definition of target Requires exacting definition of target structures and use of definitions: GTV, CTV, structures and use of definitions: GTV, CTV, PTVPTV

GTV: Gross tumor volumeGTV: Gross tumor volumeCTV: Clinical target volume = region at risk for CTV: Clinical target volume = region at risk for subclinicalsubclinical spreadspreadPTV: Planning target volume = margin added for PTV: Planning target volume = margin added for setup uncertaintysetup uncertainty

IMRT: IntensityIMRT: Intensity--Modulated RTModulated RT

Treatment typically delivered through five or seven Treatment typically delivered through five or seven beams with multiple segments treated to various beams with multiple segments treated to various intensities (i.e. intensity modulated)intensities (i.e. intensity modulated)End result is a dose distribution that closely matches End result is a dose distribution that closely matches requestrequestRequires expert physicians, expert physicists, Requires expert physicians, expert physicists, expensive technology and significant amounts of timeexpensive technology and significant amounts of time

IMRTIMRT

Radiation OncologyRadiation OncologyIMRT Treatments

0 0 0 0

837

2184

3104

5500

0

1000

2000

3000

4000

5000

6000

1999 2000 2001 2002 2003 2004 2005 2006

Year

IMRT IMRT vsvs 3D: 3D plan3D: 3D plan

IMRT IMRT vsvs 3D: IMRT plan3D: IMRT plan

IMRT IMRT vsvs 3D: 3D: DVHDVH’’ss

GTV

Esophagus

Lung

IMRT Appropriate Patient?IMRT Appropriate Patient?

IMRT clearly helpsIMRT clearly helps

IMRT: dashed line

3DCRT: solid line

Esophagus

Tumor

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IGRT: ImageIGRT: Image--Guided RTGuided RTDaily targeting of internal structures instead of Daily targeting of internal structures instead of skin marks or bony landmarks.skin marks or bony landmarks.PerformedPerformed since 2006 by since 2006 by us for all prostate us for all prostate cancers by using gold cancers by using gold ““fiducialfiducial”” seeds.seeds.Trilogy and Tomotherapy are technologies that Trilogy and Tomotherapy are technologies that provide daily provide daily ““CTCT--like imageslike images”” that are matched that are matched to planning CT images for positioning.to planning CT images for positioning.New standard for stateNew standard for state--ofof--thethe--art radiotherapyart radiotherapy

IGRT IGRT -- LungLung

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Stereotactic Radiotherapy (SRT)Stereotactic Radiotherapy (SRT)

Initially used only for cancers and disorders in Initially used only for cancers and disorders in the brain.the brain.Stereotactic Body Radiotherapy (SBRT) uses Stereotactic Body Radiotherapy (SBRT) uses similar concepts to treat cancers outside of the similar concepts to treat cancers outside of the brain.brain.SRT is SRT is notnot radiotherapy. One to five very large radiotherapy. One to five very large doses are used to doses are used to ““killkill”” everything within the everything within the defined target, i.e. radiosurgery.defined target, i.e. radiosurgery.

SRT MachinesSRT Machines

Trilogy is a modified Trilogy is a modified linaclinac that delivers SRT through that delivers SRT through setup and monitoring with a kV imager.setup and monitoring with a kV imager.CyberKnife is a dedicated SRT machine that is not CyberKnife is a dedicated SRT machine that is not designed to provide radiotherapy capability. Small, designed to provide radiotherapy capability. Small, precise beams and long treatment delivery times.precise beams and long treatment delivery times.Tomotherapy is a Tomotherapy is a linaclinac that images and delivers that images and delivers treatment through a rotational gantry (like CT). treatment through a rotational gantry (like CT). Provides image guidance with every treatment and Provides image guidance with every treatment and can simultaneously treat multiple targets quickly.can simultaneously treat multiple targets quickly.

Trilogy (Varian)Trilogy (Varian)

CyberKnifeCyberKnife

TomotherapyTomotherapy

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Evolution of TechnologyEvolution of TechnologyIntensityIntensity--Modulated Radiotherapy (IMRT)Modulated Radiotherapy (IMRT)ImageImage--Guided Radiotherapy (IGRT)Guided Radiotherapy (IGRT)Stereotactic Radiosurgery (SRS)Stereotactic Radiosurgery (SRS)TomotherapyTomotherapySpecific Disease SitesSpecific Disease Sites

HIHI--ART Tomotherapy UnitART Tomotherapy UnitLinac

Pulse FormingNetwork andModulator

DetectorBeam StopHigh VoltagePower Supply

ControlComputer

Magnetron

Data Acquisition System

Circulator

Gun Board

TomoTherapyTomoTherapy Advantages Advantages

•No Gantry-Patient Collision•No Wedges•No Gantry Angles•No Collimator Angles•No Table Angles•No Hand Pendants•No MLC Shapes or Coordinates•No MLC Motors•No Field/Jaw size•No Field Light•No Electrons•No Electron Cones

ImageImage--guided Therapy: Principlesguided Therapy: Principles

Image guidance ensures that relative Image guidance ensures that relative positions of positions of isocenterisocenter and target are the and target are the same during treatment and in treatment same during treatment and in treatment planplanThis potentially allows:This potentially allows:

Reduced treatment margins Reduced treatment margins Increased doseIncreased doseReduced complicationsReduced complicationsAvoid missesAvoid misses

Courtesy of University of Wisconsin

CT and VRCT Image sets using same window and

level adjustments

CT VRCT 2cGy

Image 1

Image 2

Image 3

Image 4

Esophagus IGRTEsophagus IGRTAfter 2400cGy (12 After 2400cGy (12 FxFx))

Original Planning CT CT of the day (TomoImage)

Courtesy: Dr. Dan Petereit M.D., Rapid City Regional Hospital T-MKT-AP0068

Stereotactic Radiotherapy Stereotactic Radiotherapy (SRT) (SRT)

for Stage I Nonfor Stage I Non--small Cell small Cell Lung CancerLung Cancer

SBRT for Stage I LungSBRT for Stage I LungInstitutionInstitution # Patients# Patients Local Control Local Control YamanishiYamanishi, Japan, Japan 257257 86%* (92%)86%* (92%)JapanJapan 131131 96%96%Aarhus (Denmark)Aarhus (Denmark) 8989 89%89%Wash UWash U 7070 83%83%Indiana U (protocol)Indiana U (protocol) 7070 88%88%Cleveland ClinicCleveland Clinic 9494 97%97%AmsterdamAmsterdam 206206 97%97%

StereotacticStereotactic-- The PatientThe Patient

SRTSRT-- The SimulationThe Simulation

4D4D--CT simulation is performed (3D plus CT simulation is performed (3D plus motion). 36 motion). 36 multislicemultislice CT synchronized with CT synchronized with chest tension belt provides images at each chest tension belt provides images at each phase of respiration.phase of respiration.Abdominal pressure plate added (when Abdominal pressure plate added (when needed) to limit respiratory motionneeded) to limit respiratory motionGating utilized (when needed) for excessive Gating utilized (when needed) for excessive motionmotion

SRTSRT-- The ImmobilizationThe Immobilization

Stereotactic Radiosurgery (SRS)Stereotactic Radiosurgery (SRS)

Requires exacting immobilization and targetingRequires exacting immobilization and targetingFiducialFiducial markers not required with markers not required with TomoTherapyTomoTherapy

StereotacticStereotactic-- The The TomoTomo PlanPlan

StereotacticStereotactic-- The SetupThe Setup

StereotacticStereotactic-- Ready to TreatReady to Treat

SRTSRT-- The TreatmentThe Treatment

Many fractionation schedules have been used, Many fractionation schedules have been used, but the but the ““winningwinning”” regimensregimens……20 20 GyGy x 3 = 60 x 3 = 60 GyGy12 12 GyGy x 4 = 48 x 4 = 48 GyGy (near sensitive structures)(near sensitive structures)

SRTSRT-- ComplicationsComplications

Emerging treatment with paucity of longEmerging treatment with paucity of long--term term data, butdata, but……Peripheral lesions: develop rib fractures in Peripheral lesions: develop rib fractures in 13/31, 9/42, 3/131, 9/8613/31, 9/42, 3/131, 9/86Apical lesions: (Apical lesions: (3737/273 pts at IU, 89% LC) 7/37 /273 pts at IU, 89% LC) 7/37 developed developed grgr 22--4 brachial 4 brachial plexopathyplexopathy (1 hand (1 hand paralysis)paralysis)Misc: Misc: bronchovascularbronchovascular fistula, fistula, pneumonitispneumonitisMultiMulti--inst study: 11/70 inst study: 11/70 GrGr 33--5 toxicity 5 toxicity

PotentialPotentialNew Clinical New Clinical

Opportunities:Opportunities:

ReRe--treatment for patientstreatment for patientsnot eligiblenot eligible

for radiation therapy for radiation therapy before before TomoTherapyTomoTherapy due to due to

cord tolerancecord tolerance

Patients courtesy Patients courtesy of University of of University of AlabamaAlabama

SRS-Applications

Highly effective and time efficientMost common sites: brain, spine, lung, liverUseful for recurrent tumors in previously irradiated fieldsTumor control is seen in 80-90% of metastases treated, but survival is not impactedCurative for Stage I lung cancers…new standard of care for medically inoperable patients

Summary

Image-Guided Radiotherapy is new gold standard for radiotherapyTomotherapy is elegant solution for IGRT and works well “out of the box”Stereotactic Radiosurgery is effective and time efficient method of palliationTomoTherapy delivers SRS as well, without need for fiducial markers

The EndThe End

igrt srt for lung cancer

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