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Varian Users Meeting at ASTRO 2006 November 4 th , 2006. Philadelphia, PA Perspectives Perspectives on IGRT on IGRT

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Page 1: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Perspectives Perspectives on IGRTon IGRT

Page 2: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Our Panel

AJ Mundt, MD

Professor & ChairMegan Gannaway, BS

Radiation Therapist

Mickey Goldman, MHA

Business Director Todd Pawlicki, PhD

Physics Director

Page 3: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

The Department

• Equipment, Trilogy (up to 40/day)• Where we are going – Vision • What we currently do with IGRT

kV/kVCBCT

SetupTreatment monitoring

Page 4: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT A Physician’s Perspective

• A long overdue technology• Known for years that….

Patients are difficult to setupTargets change in position between (inter-fraction) and during (intra-fraction) treatmentsTumors and patients change over the treatment course

• Increasingly aware that such factors effect the quality and delivery of treatment

Page 5: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

De Crevoisier et al. (MDAH)Int J Radiat Oncol Biol Phys (2005)

• Impact of rectal distension at simulation on outcome of prostate pts

• Distension correlated with PSA control

• Emphasized need for daily prostate localization with IGRT

Wake Up Call

Page 6: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

What is IGRT?

• Difficult question to answer• Image-guided RT (IGRT) means different

things to different people• No consensus exists• Some define IGRT very broadly, some

define it very narrowly• Most don’t define it at all

Page 7: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

RTOG Research Plan 2002-2006IGRT Committee ReportMichalski J, Purdy JA, Gaspar L, et al.

Int J Radiat Oncol Biol Phys 2001;51:60-5

“IGRT refers broadly to treatment delivery using modern imaging methods, such as CT, MRI, PET and Ultrasound, in target and non-target structures and in RT definition, design and delivery…”

“IGRT includes, but is not limited to, 3DCRT, IMRT, stereotactic radiosurgery, stereotactic RT, and brachytherapy….”

Page 8: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

What is IGRT?

• Prefer a more focused definition• Distinguish between

Image-based RT (use of imaging to define the target and normal tissues for treatment planning)Image-guided RT (use of imaging to monitor and modify treatment)

Page 9: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Physician Perspective

• Use of imaging to monitor and modify treatment delivery is not new

• Various IGRT approaches have been used for decades (EPID, ultrasound, video, etc.)

• What is new is modern IGRT approaches take advantage of more frequent and sophisticated imaging techniques to localize the target with even greater accuracy

Page 10: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Current IGRT Technologies

Ultrasound Video-Based Planar X-Ray VolumetricBAT Video Subtraction EPID In-Room CTSonArray Photogrammetry CyberKnife FOCAL, MSKCCI-Beam AlignRT Novalis CT-on-RailsRestitu Real-Time Video- RTRT Primaton

Guided IMRT Gantry-Mounted Varian ExaCTProtoype Tomotherapy

Tohoku, IRIS MV Cone Beam CT Commercial Siemens

Varian OBI kV Cone Beam CTElekta Synergy Mobile C-arm

Varian OBIElekta SynergySiemens In-Line

Related TechnologiesRPM gating/4DCTOptical-guided Approaches

Page 11: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

• New Department• New Cancer Center• New Staff

Chair, MDs, Physicists, RTTs, Administrators, etc

• New Varian LinacsIncluding a Trilogy

• “Ideal setting” for implementing new technologies

UCSD

Page 12: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Many Other Changes…• Large ↑ in daily census requiring addition of

new vaults and linacs• Busy SRS programs (brain, spine, and

body) using the frameless Trilogy system• ↑ Volume of labor-intensive techniques:

IMRT, pediatrics, brachytherapy, etc.• Opening of satellites• Transition to Paperless Department

Page 13: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT at UCSD• Elected to do a staged implementation• Initially focused on planar (kV) IGRT

Anatomy-based (various sites)Fiducial (seed)-based (prostate cancer)

• Straight-forward, less time-intensive • Now introducing volumetric (CBCT) IGRT

Predominantly prostate pts without seedsOther selected sites

• Plan to ↑ CBCT use, introduce 4DCT/gating and, in future, adaptive RT

Page 14: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT at UCSD• Majority of IGRT cases

Prostate CA with kV planar IGRT & fiducials• Involve the referring urologists

Seed placement (2 laterally, 1 apex)Foster a team approach

• Simulate 1 week after seed placement• Do not place seeds and simulate until after

neoadjuvant hormonal therapy• Develop a Process Flow

Page 15: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Process FlowPlanar IGRT (Prostate Cancer)

Day 1MD and RTTs meet at console

Discuss seed positions, alignments and couch shifts

Day 2 thru Completion

All shifts ≤ 1 mm LR shift > 5 mmSI or AP shift > 15 mm

Seeds drift

Other shifts

Make no shiftsand treat Call MD

Make all shiftsand treat

Page 16: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Prostate Seed MatchingProstate Seed Matching

Page 17: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Process FlowVolumetric IGRT (Prostate Cancer)

Day 1MD and RTTs meet at console

Identify mid-prostate images (axial, sagittal, coronal) and shifts

Day 2 thru Completion

All shifts ≤ 1 mm LR shift > 5 mmSI or AP shift > 15 mmDifficulty interpreting

anatomy

Other shifts

Make no shiftsand treat

Call MD

Make all shiftsand treat

Page 18: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Volumetric kV CBCT Images

Page 19: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Gynecology

• Another potentially important IGRT site

• All gynecology pts at UCSD treated with IGRT

• Highly conformal IMRT plans make IGRT important

Notoriously difficult to setup patients

Page 20: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Gynecology• IGRT also crucial since

we are trying to spare the pelvic bone marrow

• Difficult since it is important to reduce the low receiving low doses (V10 and V20)

• All gynecology pts thus undergo on-line kV IGRT setup (boney matching)

Page 21: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Page 22: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Gynecologic IG-IMRT

• To evaluate the benefit of volumetric IGRT approaches in gynecology, a CBCT is also obtained daily

• Unlike kV imaging, it is obtained post-RT and analyzed off-line

• Ensure target coverage and evaluate impact of re-planning (adaptation)

Page 23: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Process FlowIGRT (Gynecology)

Day 1MD and RTTs meet at console

Discuss anatomy and shifts

Day 2 thru Completion

All shifts ≤ 1 mm Any Shift > 10 mm Other shifts

Make no shiftsand treat

Call MD Make all shiftsand treat

CBCT

Page 24: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Gynecologic IGRT

• CBCT will eventually replace planar kV imaging for setup evaluation

• CBCT will also be used for adaptive treatment planning

Page 25: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Bladder

Rectum

Tumor

Bladder

Tumor

Rectum

PrescriptionIsodoseWeek 1 Week 3

TumorsShrink

Page 26: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

• 14 cervical cancer pts undergoing RT• MRI before RT and after 30 Gy• Used to generate 2 IMRT plans• Assessed impact of re-planning on

target coverage and normal tissue sparing

Page 27: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

• GTV decreases on average by 46%• Re-planning improved rectal sparing• If >30cc GTV reduction, re-planning also

improved sparing of the small bowel

Pre-RT 30 Gy

GTV

Page 28: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Currently use CBCT for daily setup and adaptive RT in re-irradiation patients56 yr old stage IIIB cervical cancer pt56 yr old stage IIIB cervical cancer ptRecurs 3 yrs following definitive chemoradiotherapyRecurs 3 yrs following definitive chemoradiotherapyIsolated recurrence in PA node at L4Isolated recurrence in PA node at L4--L5 (L5 (½½ in old field)in old field)IMRT 59.4 Gy in 1.8 Gy fractions plus CDDPIMRT 59.4 Gy in 1.8 Gy fractions plus CDDP

Excellent palliative response, minimal toxicityExcellent palliative response, minimal toxicity

Page 29: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT A Physicist’s Perspective

• Image-guided radiotherapy is being overvalued as a clinical tool in radiation therapy

• Presented as a Point/CounterpointMed Phys (33) Oct 2006Howard I. Amols, Ph.D.David A. Jaffray, Ph.D.

Page 30: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT in Radiotherapy

0.0

0.2

0.4

0.6

0.8

40.0 50.0 60.0 70.0 80.0

Dose (Gy)

0.00

0.05

0.10

0.15

0.20RT Failure Function (F)Quality Distribution

Expected Failures E<F>

Figure 2

F = 1 − [TCP·(1−NTCP)]

Page 31: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT in Radiotherapy

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

16.0%

18.0%

-6.0% -4.0% -2.0% 0.0% 2.0% 4.0% 6.0% 8.0%

Per cent deviation from prescription dose

Expe

cted

radi

othe

rapy

failu

re

0.5Gy SD1.0Gy SD2.0Gy SD3.0Gy SD4.0Gy SD

Figure 3

0.5 σ

4.0 σ

Page 32: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT in Radiotherapy

• Theoretical evidence – Improving quality and precision may increase survival and decrease complications

• 1988 Publication – Effects of dosimetric and clinical uncertainty on complication-free local tumor control

Boyer AL, Schultheiss T. Radiother Oncol. 1988 Jan;11(1):65-71.

Page 33: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT A Physicist’s Perspective

• How can one use IGRT today?Precise and accurate imagingTreatment monitoring

• Quality AssuranceWhat and how?

• Training on image interpretation • What is exciting about IGRT for physics?

Page 34: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Daily Prostate Localization

Page 35: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Treatment Monitoring

• Easy to import into Eclipse

Page 36: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

OBI Clinac HW ModificationsSupervisor

GeneratorIn 480 VOut 125kV

Auxiliary electronicsCarousel cntrlGantry encoder

kV HV cable takeupIAS3 DU A-to-DPower shelf

MV Detector

Exact Arm

Laser GuardMtn

CntrlRack

RPM Gating Camera

SRS/SRT 6x filter

SRS Collimator

X1/X2 CollSPRO

Lat, Long, VrtSPRO

Rotation SPRO

kV Source

kV Detector

Page 37: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT QAThings to consider when implementing IGRT

• Safety and functionality• MV/kV isocenter coincidence• Geometrical accuracy (arm position)• Shift calculation (MV/kV, kV/kV, CBCT)• OBI isocenter vs gantry angle• Image quality (kV, CBCT)• CBCT image uniformity• CBCT HU constancy

Page 38: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

QA on the Trilogy• Safety and functionality• MV/kV isocenter coincidence• Geometrical accuracy (arm position)• Shift calculation (MV/kV, kV/kV, CBCT)• OBI isocenter vs gantry angle• Image quality (kV, CBCT)• CBCT image uniformity• CBCT HU constancy

Page 39: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

kV/MV Isocenter Coincidence

Page 40: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

kV/MV Isocenter Coincidence

Sua Yoo et al. A quality assurance program for the on-board imager.Accepted for publication in Med Phys.

Collaborative effort: Duke, Emory, Henry Ford, Stanford, and Varian

Page 41: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT Is Not Done Evolving

Picture courtesy of Steve Jiang, PhD; MGH

Page 42: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

IGRT A Therapist’s Perspective

Page 43: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

How kV/kV impacts the schedule

• Until staff is comfortableSchedule half hour for kV/kV matching

• Evaluating the images takes time• After a few months

kV/kV matching only adds about 5 min to a patients total treatment time

• Comfort with the softwareHardware takes 2-3 months for each therapist

Page 44: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

How CBCT impacts the schedule

• 45 min time slots until staff is comfortable

• 30 min schedule for CBCT patients

• Some patients are CBCT once a week, some daily

• Patients must be able to hold still at least 30 min

Page 45: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

A typical day on the TrilogykV/kV

Anatomy40%

non-IGRT15%

CBCT Prostate

19%

CBCT Other

6%

kV/kV Seeds20%

Page 46: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

How do we use kV/kV

• Manually match• Fiducials for prostate• Bony anatomy

PelvisHead and neckThorax (though this is more difficult)Any difficult setup

Page 47: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

How do we use CBCT

• Prostate without fiducialsManually match the borders of the prostate with the contours from Eclipse

• Other selected patients (GYN, etc.)

Page 48: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

What patients think about kV/kV

• Patients are curious • Patients request kV/kV• Patients are rarely concerned about the

length of time on the table• Patients are reluctant to be treated

without kV/kV

Page 49: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

What patients think about CBCT

• Patients initially unhappy about time on treatment table

• Once patients understand CBCT More than happy to be on the table for 30 min

• Prostate patients with a full bladder are sometimes uncomfortable

• Non-compliant patients might not be great candidates

Page 50: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Difficulties with kV/kV and CBCT

• Considerable training is needed• Interaction between software programs

Troubleshooting errors • Evaluating images can be difficult • Spending less time with the patients

Page 51: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

What do RTTs like about kV/kV

• Effective and reproducibleInternal anatomy or seeds are localized daily

• Less “chasing” external marks• Easy to analyze with training• Time efficient

15 min time slot possible

Page 52: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

What do RTTs like about CBCT

• It’s interesting technologyImagingAnatomyQA

Page 53: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

QA for kV/kV and CBCT

• Daily warm-upkV source must be warmedCoincidence check between kV and MV

• Practice, practice, practiceCBCT a phantom early on to practice:

Hardware and software usage

Page 54: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

In a perfect world…

• Set up an IGRT protocol before clinical routine clinical use

Cases/Sites, imaging frequency, procedures, thresholds, etc.

• Physicians – Please educate RTTs on image interpretation

• Physicists – Please be near by to troubleshoot problems

Page 55: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Where’s the BEEF?!

Page 56: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

A Business PerspectiveA Business Perspective

• Goal is to differentiate yourself in the marketplaceImage guided therapies are becoming the new standard of care

• Clinical Program Development• Educate referring physicians

Most significant impact• Public education

Website design• Advertising

Page 57: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Determine impact on the business• New equipment or upgrade to existing

technology?• Determine implications on existing capacity

Do we have excess capacity?How will we accommodate increased treatment time?

• What will be the impact on the treatment schedule?

• Training issues

Page 58: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Prepare the business• Billing setup

Update hospital charge masterUpdate Varis/Aria procedure detail masterCheck interface to ensure information is being transmitted and accepted accuratelyEducate billing & collection staff of new procedure codes

Page 59: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Reimbursement Issues• On Board Imaging (OBI) - 77421

Stereoscopic x-ray guidance for localization of target volume for the delivery of radiation therapy – used for positioning of the patient

Must use kV or MV x-rays onlyHas both a technical and professional componentAPC 1502 – payment rate $75.00

2007 proposed change to APC 0257 & payment reduction to $60.14

Page 60: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Reimbursement IssuesReimbursement Issues• Cone beam CT (CBCT) – 76370

Computed tomography for placement of radiation therapy fields – use for daily CT for planning.Technical charge only – for both hospitals and freestanding centersMust have case by case orders from the MD as to why the procedure is being done and frequency of useAPC 0282 - $94.82

Page 61: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Source – James Hugh III- AMAC

Page 62: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Website

Page 63: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Page 64: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Page 65: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

AdvertisingAdvertising• Newspaper• Billboards• Advertorials• Brochures• Radio• Television

AdsHealth related talk shows

Page 66: Igrt Perspectives

Varian Users Meeting at ASTRO 2006November 4th, 2006. Philadelphia, PA

Perspectives Perspectives on IGRTon IGRT

QUESTIONS??