what should you take away - healing, teaching & discovery · what should you take away from...

What should you take away from this presentation?

• A better understanding of how treatment machines can affect:

– Cancer Care Facility

• Radiation Therapists

• Radiation Oncologists

• Medical Physicists

• Dosimetrists

• Patient Satisfaction

HISTORICAL MILESTONES

Wilhelm Conrad

Roentgen German Physicist

Discovery of X-rays

in 1895

The Advent of Radiation Therapy

Machines

– Legacy Hospital

– Portland, Oregon

– Cobalt 60

– OHSU’s 1st Radiation Therapy Machine

– Commissioned in 1953

VanDe Graff Machine

Peacock System on Linac 6100

11

OHSU’s Latest Treatment Modalities • Varian Trilogy • Tomotherapy • Varian/Novalis

– Brain Lab – Exactrac

• Calypso • Philips CT SIM • Brachytherapy

– HDR – Eye plaques

• Intrabeam • Hyperthermia

–Photon Energies

• 6 MV

• 23 MV

–Electron Energies • 6 MeV

• 9 MeV

• 12 MeV

• 16 MeV

• 20 MeV

CBCT (Cone Beam Computed Tomography)

Imaging kV/kV

Imaging

MV

Common Treatments Used For This Machine

Prostate Breast Lung Heterotopic Ossification Whole Brain Sarcoma Multiple Myeloma

Total Body Irradiation Bone Marrow Transplant

Total Skin Irradiation Mycosis Fungoides

Anal Rectal Lymphoma Head & Neck Cranial Spinal

Table and Field Limits

•Table Limit: •440 lbs

•Field Limit: •40cm x 40cm •120 MLC leafs

•80 leafs are 0.5 cm •40 leafs are 1 cm

TomoTherapy • Energy

–6 MV

–No electron capabilities

TomoTherapy Imaging - MVCT

Table Limits: 440 lbs

Field Limits • Longitudinal:

– Controlled by Jaws

• 5cm, 2.5cm, and 1cm

– Maximum Longitudinal treatment field

• 145 cm

• Ant/Post and Left/Right

– Limited by the Field Of View

• FOV is 40 cm across

Leaf Thickness

• Leaf Thickness

– 10 cm

• Leaf Width

– 0.645 cm

• Number of Leafs

– 64 cm

Tomo MLC Shapes

Tomo Beam

Common Treatments • H&N Cancers

• Pancreas

• Liver

• Esophagus

• Rectal

• CranioSpinal

H-N

Pancreas

Craniospinal Re-Irradiation

NovaLis ExacTrac

• Energies

–6 MV

–10 MV

• Electron Capable

• Weight Limit

–315 lbs

Novalis

30

• MLC

–28

• ¼ cm leafs

–64 • ½ cm leafs

• Field dimensions

–22 wide by 32 long

Field

Limits

ExacTrac Imaging

32

Common Treatments • SBRT

–Lung

–Liver/Pancreas/Gallbladder

• SRS/SRT

–Pediatric Tumors

–GBM

Varian Trilogy

Tomo Therapy

Case Description • 4 year old male

• PNET (Primitive Neuro Ectodermal Tumour)

• Underwent gross total resection

• Dose – 36 Gy to the craniospinal axis

• Posterior Fossa Boost – 55.8 Gy

Set Up Considerations Tomo: Patient Supine on

VacLoc. VacLoc pushed up to U-Frame with “A” headrest

Varian: Patient Supine on

VacLoc VacLoc pushed up to U-Frame with “A” headrest

• Tomo (MVCT) – Scan 4cm at L-Spine

• Make shifts to patient, not table

• Write down table corrections

– Scan 4cm at T-Spine


– Scan 4cm at C-Spine


– Scan from mid-skull to mid C-spine

• Compare table corrections

Comparing Tomo vs. Varian

IMAGING PROCEDURES Time: 15 to 25 min


IMAGING PROCEDURES • Varian

– Day 1 • 9 to 12 images- one for each field

– 3 Right Lateral MV Portals – 3 Left Lateral MV Portals – 3 Posterior/Anterior MV Portals

» 3 more if the spine field is long

• Time – 25 to 35 min

– Once a week • Lat and AP MV Portal • Time

– 4 to 7 min

Treatment Considerations

• Tomo –After imaging

and shifts • Watch patient

for movement

• Varian –After imaging and

shifts • Watch patient for

movement

• Table kicks (Yaw)

• Field matching

• Feathering

• Energy

– 6MV

• Duration

– 9 min 1.3 sec

• Gantry Rotations

– 19

• Couch Travel (Y-axis)

– 61.5 cm

TomoTherapy Plan

Varian Trilogy Plan • Rt Lat Brain Field

– Gantry: 270

– Collimator: 10

– Couch Rotation: 8

– Y1: 12.6, 13.1, 13.6 cm

• Lt Lat Brain Field – Gantry: 90

– Collimator: 350

– Couch: 352

– Y1: 12.6,13.1, 13.6

• Energy – 6MV

• PA Spine Field – SSD: 100

– Y2: 18, 17.5, 17 cm

What Modality Was Selected And Why

• The homogeneity of the dose was improved with the TomoTherapy plan

• The Tomo plan was able to decrease – Dose to the

• Brain Stem • Spinal Cord • Heart • Right and Left Cochlea • Pituitary

– Exit doses of all other organs

• All vertebral bodies received a dose of 15 Gy – Will allow consistent growth across the volume of the

patient’s vertebral body

Dose Volume Histogram

• Tomo Max Dose

– 38.5 Gy

• Varian Max Dose

– 39.4 Gy

Brain Stem


• Tomo Max Dose

– 37.9 Gy

• Varian Max Dose

– 42.2 Gy

Spinal Cord


• Tomo Mean Dose – 23.7 Gy

• Varian Mean Dose – 38.2 Gy

Rt Cochlea

Lt Cochlea • Tomo Mean Dose

– 24.6 Gy • Varian Mean Dose

– 38.3 Gy


• Tomo Mean Dose

– 2 Gy

• Varian Mean Dose

– 25.2 Gy

Heart


• Tomo Mean Dose

– 37.6 Gy

• Varian Mean Dose

– 37.9 Gy

Pituitary

Side Effects Acute

• Brain injury • Patient had learning

disabilities from birth and after resection surgery

• Hearing loss

• Possible radiation necrosis in cerebellar peduncle

Chronic • Fatigue

• Skin erythema

• Taste changes

• Hair loss

• Nausea

• Vomiting

• Loss of appetite

• Weight loss

• Low blood counts

• 6 months after Radiation treatment

– Increased Appetite

– Improved memory

– Improved muscle strength

– Truncal weakness

• Tumor enhancement found on MRI 7 months after treatment

Patient Outcome

Patient Satisfaction • Patient, though young, was not afraid of the

TomoTherapy Unit

• Patient’s parents were concerned and intimidated at first

– They felt comfortable after explanation of TomoTherapy

Case Description • 78 year old woman

• Unresectable adenocarcinoma of the pancreatic head – 2.3 x 2.2 cm

• with involvement of the hepatic arteries and SMA

– T4N1

• RT w/ concurrent Xeloda – Dose: 45Gy + 14.4 Gy Boost to 59.4 Gy (33 fractions)

– Fiducial marker placement to assist in imaging

• Followed up by Gemcitabine

Set Up Considerations • TomoTherapy

– Supine – VacLoc – Wing Board – Knee Sponge – Bilateral Levelers and SCI

• Varian Trilogy – Supine – VacLoc – Wing Board – Knee Sponge – Bilateral Levelers and SCI

• Tomo (MVCT)

– Scan 15 to 25 slices

• 6 mm each slice

– Time

• 2 to 3 minutes


IMAGING PROCEDURES


IMAGING PROCEDURES

• Varian

– Cone Beam

• Time – 2 ½ to 3 ½ min

– ExacTrac

• 1 min

TomoTherapy Plan • Energy

– 6MV

• Duration

– 2 min 40 sec


– 14


– 8.19 cm

Varian Trilogy Plan • ARC Field 1

– Clockwise

– Gantry: 181 – 179 deg

– Collimator: 10 deg

– MU: 179

• ARC Field 2

– Counter Clockwise

– Gantry: 179 – 181 deg


– MU:224

• Energy

– 10 MV


– Both plans were nearly the same • Tomo gave less dose to the spinal cord

– The implanted gold markers were not visualized well on the TomoTherapy unit

– Moved to the Varian Trilogy after 540 cGy


• Tomo Max Dose

– 73.6 Gy

• Varian Max Dose

– 76.3 Gy

Spinal Cord


• Tomo Max Dose

– 45.4Gy

• Varian Max Dose

– 45.3 Gy

Liver


• Tomo Max Dose

– 37.2 Gy

• Varian Max Dose

– 37.3 Gy

Rt Kidney


• Tomo Max Dose

– 20.5 Gy

• Varian Max Dose

– 14.1 Gy

Lt Kidney

Tomo vs. Varian

IMAGING COMPARISONS MVCT (Tomo) CBCT (Varian)

Tomo vs. Varian

IMAGING COMPARISONS MVCT (Tomo)

CBCT (Varian)

Tomo vs. Varian

IMAGING COMPARISONS MVCT (Tomo) CBCT (Varian)

• Fatigue

• Abdominal pain

• Slight weight loss

• Slight Appetite loss

• Back Pain

• Nausea

– Was under control by end of treatment

• Dry mouth

Side effects

Patient Recovery • Fatigue began to decrease a week or two after

treatment finished

• Appetite increased

• Back pain did not subside

• Patient was found to have systemic disease 2 months after treatment

Patient Satisfaction

• Patient felt intimidated by the machine

– Overly complicated treatment

– Fear of the unknown was a factor at first

Varian Trilogy

TomoTherapy

Case Description • 60 year old Male

• T3N2bM0 squamous cell carcinoma of the right tonsil

• P16 positive tumor treated with chemoradiotherapy

• Cisplatin (3 Cycles)

• Dose

– 70 Gy (35 fractions)

Set Up Considerations • Tomo

– Aquaplast mask with “B” headrest on Halycon board

• Varian

– Aquaplast mask with “B” headrest on Halycon board

• Tomo (MVCT)

– Scan 20 to 30 slices

• 4 mm each slice

– Time

• 3 to 4 minutes


IMAGING PROCEDURES


IMAGING PROCEDURES

• Varian

– CBCT (Cone Beam)

• Time – 2 to 3 minutes

Tomo vs. Varian

IMAGING QUALITY MVCT (Tomo) CBCT (Varian)

• Tomo – After imaging and shifts

• Watch patient for movement

• Varian – After Imaging and shifts

• Watch patient for movement during Arcs

– Some treatments involve table kicks (Yaw adjustments)

Treatment Considerations

• Energy

– 6MV

• Duration

– 5 min 44 sec


– 28.6


– 20.5 cm

TomoTherapy Plan

Varian Trilogy Plan • Energy

– 6MV

• ARC Field 2

– Clockwise

– Gantry: 179 – 181 deg


– MU: 252

• ARC Field 3


– Gantry: 260 – 100 deg


– MU:103

• ARC Field 1


– Gantry: 181 – 179 deg


– MU: 258


• Varian decreased dose to:

– Spinal Cord

– Left Parotid

– Right & Left Cochlea

• Tomo decreased dose to:

– Mandible

– Hyoid

– Right Parotid




Rt Cochlea

Lt Cochlea • Tomo Mean Dose


– 3.9 Gy


• Tomo Max Dose

– 45.02 Gy

• Varian Max Dose

– 43.48 Gy

Spinal Cord




Rt Parotid

Lt Parotid • Tomo Mean Dose


– 28.1 Gy


• Tomo Max Dose

– 73.6 Gy

• Varian Max Dose

– 76.3 Gy

Mandible


• Tomo Max Dose

– 72.5 Gy

• Varian Max Dose

– 76.3 Gy

Hyoid

Side Effects • Last week of treatment:

– Mucositis

– Weight loss

– Brisk Erythema

– Extremely tired

– Sore throat

• Not eating much

• Drinking a bit

Side Effects/Recovery

• 3 months after treatment – Sore tongue

– Small amount of bone exposure on the left lingual surface of mandible

– No thrush, No mucositis

– Tonsils looked good

– Edema of the epiglottis and the arytenoids

– True cords looked good and moved freely

– Weight loss

Side Effects/Recovery

• One year out from treatment: – Eating well

– Swallowing fairly well

– Had dry mouth

– No sore throat

– No ear pain

– No cough

– He is very active in delivering phone books

Patient Satisfaction • Claustrophobic

– Had trouble with the mask and being in the bore the first 3 days

• Near the end of treatment patient felt treatment was almost not worth the effort

• 3 months/6 months/1 year later patient was very satisfied with the experience as a whole

How does it affect your facility’s workflow?

OPINIONS

TomoTherapy • Fear of losing patient set-up skills • MVCT for every patient can add up

– Time – Dose

• Boring – Nothing to do while patient is being

treated but watch the patient for movement

• Uncomfortable not being able to see the movement of the gantry and MLC’s

• If plan is changed tomo does not update the remaining fractions

• Takes time for patient to come out of bore in case of emergency

• The image quality could be better – It would be nice if kV imaging were

available

Varian Trilogy

• Needs a button that automatically takes the gantry and collimator to the zero position

• The image quality of the Port Films are not very good

• Clearance issues with the electron cone at 100 SSD

• Software crashes too often – Can take up to 10 minutes to correct

NEGATIVE

Opinions of Radiation Therapist (22)

Opinions of Radiation Therapist

Varian Trilogy • Can see patient with few

obstructions

• Can see movement of gantry, colli, and MLC’s during treatment

• Standard workhorse with solid imaging basics

TomoTherapy • Extremely easy to operate

compared to other machines

• Better treatment capabilities for pediatrics

• Dose is tracked by time and MUs – Same amount of time for every

fraction

• Can choose to avoid areas when doing a scan

POSITIVES

Opinions of Dosimetrists (5)

TomoTherapy • Can not do adaptive planning

as well as the Varian Trilogy

• Can not treat overly wide treatment fields

• When planning – Have to consider images quality

of MVCT

• Can not see TACE or gold seeds

Varian Trilogy • Patients can be accessed by

multiple users

– Plans can be altered by other user when saved without your knowledge

NEGATIVES

Opinions of Dosimetrists

TomoTherapy

• Excellent with long treatment fields

• Works well for midline structures – ie. Liver, Spine,…

Varian

• Can treat a wider scope of diseases

• Planning system is user friendly • i.e. Eclipse’s has a better resolution

when contouring

• Can create plans using automatic computer interpolation

POSITIVES

Opinions of Radiation Oncologists (5)

TomoTherapy • Seem to have side effects with

prone anal plans

• Length of the treatment times

• MVCTs are harder to read for image guidance

Varian Trilogy • Can not adjust for roll

• Does not treat long fields uniformly

NEGATIVES

Opinions of Radiation Oncologists

TomoTherapy • Varian can do almost any

treatment

• Can adjust for Yaw

• Easier for creating plans

Varian Trilogy • Better at concave structures

– Ie: head and neck

• Fewer setup variables on a day to day basis – Fewer opportunities for errors

– ie. Wedges, gantry angle, table angle

• Plans look better than Varian on large treatment volumes

• MVCTs are good for pts with hardware after surgery

• TOMO can adjust for roll

POSITIVES

Opinions of Physicists (6)

TomoTherapy • QA’s take longer

– Not able to use the same Isocenter for every patient’s QA

– Have to go back into the room and reset for each patient’s QA

• No clear separation for service mode • Needs dose technique options for MVCT

– Adjust for scanning different body thickness

• Drawing tools for structures are bad • Software support for film and water

scanner could be improved • Image quality could be better • Adaptive planning too complex

– Software tries to do too much

• Weekly chart checks have to be manually put into ARIA

– Corrected if have latest software version of Aria and Tomo

Varian Trilogy • CBCT’s algorithm can be 10% or

more off – Can not use image for planning

• Very difficult for commissioning – All the systems have to be

integrated

• IMRT (Rapid Arc) is not as good as TomoTherapy – Better if it could handle more data

• Then able to do more than 3 Arcs • There is more beam modulation

with its step and shoot than its Arcs – Limited to about 9 fields

» Leakage/Time

– Can’t handle the same amount of modulation

• Only good enough for prostate

NEGATIVES

Opinions of Physicists

TomoTherapy • Inverse planning easier than

other’s

• MVCT superior to CBCT – Can be used for planning

• High degree of beam modulation – Can manipulate beam more

Varian Trilogy • Easy well established QA system

• Planning tools are very user friendly

• Can treat nearly any type of cancer efficiently

POSITIVES

Opinions of Patients

TomoTherapy • Gantry head is intimidating

• Creaking noise of gantry – Worry it will fall

Varian Trilogy • Tomo bore can cause some

claustrophobia

• Tomo can be loud – Because of the cooling fans and leaf

movement

Conclusion • Both the TomoTherapy and Varian Trilogy machines have their positives

and negatives • The biggest complaints with the TomoTherapy:

– Poor imaging – Lack of flexibility with the software

• The biggest complaints with the Varian Trilogy: – Glitches in the software

• Causing down time

– Inability to treat long fields • Without feathering or matching

• The most mentioned positives about TomoTherapy: – Not having to worry about the gantry and table position during treatment – Ability to treat long fields

• The most mentioned positives about the Varian Trilogy: – It can handle almost any type of treatment – You can see the actual field on the patient

Bibliography

IMAGES 1. http://faculty.ksu.edu.sa/73860/Pictures%20Library/Forms/DispForm.aspx?ID=11 2. http://www.zimmerspine.eu/z/ctl/op/global/action/1/id/9027/template/PC/navid/9989 3. http://avandia-sideeffects.com/ 4. http://www.rsc.org/chemistryworld/Issues/2007/February/FirstDrugFatDogs.asp 5. http://jessicambabyblog.blogspot.com/2011/07/baby-genius.html 6. http://www.personal.psu.edu/afr3/blogs/SIOW/2011/10/the-elephants-trunk.html 7. http://www.greatlandings.com/2012/06/22/my-heart-will-go-on/ 8. http://www.marshfieldclinic.org/patients/?page=ent_ear_cochlea 9. http://www.nlm.nih.gov/medlineplus/pituitarydisorders.html 10. http://themusicgates.blogspot.com/2011/07/rolling-stones-i-cant-get-no.html 11. http://radiology.rsna.org/content/255/2/578.figures-only 12. Thank you to

1. Varian 2. Novalis 3. Accuray (Kelly McDonald) 4. Coworkers 5. Chief therapist 6. Onocologists 7. Physists 8. Dosimitrists

http://faculty.ksu.edu.sa/73860/Pictures Library/Forms/DispForm.aspx?ID=11

http://www.zimmerspine.eu/z/ctl/op/global/action/1/id/9027/template/PC/navid/9989

http://avandia-sideeffects.com/



http://www.rsc.org/chemistryworld/Issues/2007/February/FirstDrugFatDogs.asp

http://jessicambabyblog.blogspot.com/2011/07/baby-genius.html



http://www.personal.psu.edu/afr3/blogs/SIOW/2011/10/the-elephants-trunk.html





http://www.greatlandings.com/2012/06/22/my-heart-will-go-on/









http://www.marshfieldclinic.org/patients/?page=ent_ear_cochlea

http://www.nlm.nih.gov/medlineplus/pituitarydisorders.html

http://themusicgates.blogspot.com/2011/07/rolling-stones-i-cant-get-no.html











http://radiology.rsna.org/content/255/2/578.figures-only




Contact Info

Email: [email protected]

what should you take away - healing, teaching & discovery · what should you take away from...

Documents