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FIRST SBRT TREATMENT
IN WINDSOR ONTARIO
Ming Pan M.Sc., M.D., FRCPC
Radiation Oncologist, Windsor Regional Hospital Cancer Program
Adjunct Professor, Department of Oncology
Schulich School of Medicine & Dentistry
University of Western Ontario
Disclosure
I have no conflict of interest.
Background
According to our 2010-2015 preliminary planning
of Radiation Oncology Program, we should develop
SBRT in Windsor before the 2015-2016 fiscal year.
 This planning was delayed due to an inappropriate
recommendation against the SBRT in our relatively
small program by an expert external review in 2011.
Since then almost all other programs in Ontario
have developed SBRT despite their size.
Background
In these 5 years we developed IMRT, VMAT,
IGRT with daily CBCT guidance, MRI simulation
and 4D-CT simulation in our local cancer program,
(almost all the state-of-the-art technology that other
centers have dreamed of).
Our new cancer patient # seen by Rad Onc service
increased from 1,235 to 1,509 per year.
But….we have been referring Windsor patients to
London, Hamilton and even Toronto for SBRT.
We finally delivered the 1st SBRT to a lung cancer
patient in October 2015.
What is SBRT?
Stereotactic Body Radiation Therapy (SBRT) is a treatment
procedure similar to central nervous system (CNS) stereotactic
radiosurgery, except that it deals with tumors outside of the CNS.
A stereotactic radiation treatment for the body means that a
specially designed coordinate-system is used for the exact
localization of the tumors in the body in order to treat it with
limited but highly precise treatment fields.
SBRT involves the delivery of a single high dose radiation
treatment or a few fractionated radiation treatments (usually up
to 5 treatments).
http://radonc.ucla.edu/sbrt
SRS: Stereotactic Radiosurgery.
Stereotactic from “Stereotaxis” - Greek for “Solid” and
“Orderly” - Originally for surgical path to cranial lesions.
Then frame-based
radio-surgery –
frame used to target
'radio-ablation'
SBRT: Stereotactic Body Radiotherapy
4D CT simulation
How Did We Get Here?
CMEs
Lots of research
Site visit to JCC in Hamilton
New equipment purchases
Development of new policies and procedures
Staff training
Ongoing review and changes to process
Challenges to Start SBRT
Improving immobilization and indexing to CT
simulation and treatment bed
Scheduling (QA, SBRT treatment staff)
Time to create policies and procedures
Training staff on new equipment
Technical/software difficulties
Learning curve – become more efficient with each
treatment
4D CT SIM - Immobilization
CT-SIM time for SBRT 90 mins(45 mins for CRT)
SBRT need Orfit immobilization device and
Vacloc (vacuum bag) extend from above the
shoulders to below the hip joint (4 therapists reqd)
Need maximizing comfort to ensure patient
compliance and couch position reproducibility
CRT requires a vacloc and wingboard for
shoulder and arm immobilization only (2 therapists
minimum to form)
Headboard (indexed in 2 locations)
Arm Support
Knee and Foot Support (both indexed)
Long Vacloc
Compression Plate
Compression Arch
CT SIM - Scanning
• Patients have 2 CT scans (as do radical lung patients following the 4DCT
protocol)
• A respiratory tracking belt is placed around patient to track breathing
• Physicist and physician will be present to assist, review the 4DCT, assess
tumour size (max 5.0 cm) and motion
• If tumour motion is > 1.0 cm, the 4DCT should be repeated with
abdominal compression.
• If size and motion acceptable, scanning continues with a second helical
(3D scan)
Treatment Planning
● Contouring
is extensive – many structures required...
Treatment Planning
• Physicians contour tumor and
Dosimetrists contour normal
organs and structures
• “Virtual” patient model built in
treatment planning system
(TPS)
• Impact of different beam
shapes, directions, intensities
assessed
• Goal is to reduce normal
tissue damage risk, increase
tumour control probability, by
concentrating dose in tumour
• Optimal “Treatment Plan” is
then delivered to patient...
Quality Assurance
•
Every morning, standard quality assurance tests are performed on each linear
accelerator from 6-7am by a radiation therapist
•
On SBRT days, additional SBRT-specific “Winston Lutz” QA (WLQA) is done directly
after regular morning QA from 7-8am by a therapist on the SBRT team
•
Once WLQA is complete, a physicist double checks the results and gives the goahead for treatment that day
•
Isocentre alignment becomes more and more critical as target sizes become very
small, as is the case for SBRT (WLQA tolerance = 1.6mm vs. 2mm for regular QA)
•
An additional monthly QA test is also performed by physics
Treatment Delivery
• SBRT lung booking = 60 min(CRT=15min)
• First day patient education/ongoing patient care
• MRTTs set up Orfit immobilization device (5-10 min)
• Patients are brought into the room and positioned (15-20 min)
• CBCT – treat – CBCT = approx. 20-25 min
• Physician present to approve CBCT prior to Tx delivery and
perform abdominal compression if required
• Physicist present for Tx delivery for troubleshooting
Daily Cone Beam CT=IGRT
LUSTRE trial
A Randomized Trial of Medically-Inoperable
Stage I Non-Small Cell Lung Cancer Patients
Comparing Stereotactic Body Radiotherapy Versus
Conventional Radiotherapy (LUSTRE)
Protocol Number: OCOG-2013-LUSTRE
LUSTRE trial
To determine if SBRT is more effective than CRT
for patients with stage I NSCLC who prefer
radiation due to high operable risk, or are deemed
medically inoperable.
Primary end point is rate of local control.
Secondary objectives for comparison include
survival, quality of life, and toxicities.
Multi-centre randomized controlled trial, to be
conducted at 16-20 centres across Canada.
Eligible patients will be randomized to receive
SBRT or CRT in a 2:1 ratio, and treatment is to
follow as soon as possible, and within 3 wks post
randomization.
LUSTRE Sample Size and
Feasibility
NCIC BR25 (60Gy/15): 2-yr LC 88% with
estimated 3 yr LC 75% at best with CRT.
We expected SBRT result in a minimal clinically
important increase of 12.5% in 3-year LC to 87.5%.
Min 59 events: 85% power to detect a difference
of this magnitude (HR=0.46) with a two sided
α=0.05 and a 2:1 (SBRT:CRT) randomization
Assuming 3 years for patient recruitment with an
additional 2 years of follow-up, we would require a
total sample size of 308 patients.
Add 5% inflation factor for non-compliance and
losses to F/U, we need a total of 324 patients (216
SBRT and 108 CRT patients).
LUSTRE trial
Experimental arm (SBRT) receives 48 Gy in 4
fractions of 12 Gy, separated by at least 24 hrs. If
the tumour is not peripheral, then a modified dose
of 60 Gy in 8 fractions of 7.5 Gy will be used. The
overall SBRT treatment course will be given over 414 days.
Control arm (CRT), 3D conformal or IMRT is
allowed. The prescribed dose is 60 Gy in 15
fractions of 4 Gy delivered daily over 3 weeks.
In both cases, the preferred technique at WRCC
will be VMAT with multiple arcs, or multi-field 3DCRT, if necessary.
LUSTRE trial
Case #1
81-year-old lady with presumed non-small cell lung
cancer in the left lingula that had doubled in size on CT
scan over one year.
PET scan from May 1, 2015 showed SUV 10.5 in the left
lingula nodule that measured 1.2 x 1.6 cm in size. There
was no evidence of any distant or lymph node metastases.
Long history of severe COPD, chronic bronchitis and
emphysema. On home oxygen all the time.
Multiple hospital admissions for COPD exacerbations.
Not candidate for biopsy or surgery.
Case #1
Participated in OCOG-2013-LUSTRE trial after
informed consent.
Randomized into SBRT arm.
Had 4-D CT simulation followed by SBRT 4,800 cGy in
four fractions between October 28 and November 4, 2015.
Tolerated treatment well with no significant side effects.
st
1
Follow up in January
First post-treatment CT scan of the chest from
December 29, 2015 showed excellent response.
 Primary cancer almost completely disappeared on
mediastinal window, with no measurable tumor.
Lung window:Scaring appearance measuring 1.4x1.3cm
Previously it measured 2.4 x 1.7 cm on September 8,
2015.
Pre- and Post-SBRT CT
CT: 8 weeks before and after SBRT
Pre- and Post-SBRT CT
CT: Lung window
Follow up in April 2016
She has been doing very well since SBRT.
No new respiratory symptoms or worsening symptoms.
Continues to have shortness of breath due to her known
COPD, chronic bronchitis and emphysema.
She is still on home oxygen.
ECOG=1
Pre- and Post-SBRT CT
CT: 2 months before and 5 months after SBRT
Conclusions
SBRT is finally available in WRH Cancer Program.
Our 1st SBRT outcome is favorable.
We will continue LUSTRE trial (had 5 cases now).
No need for central review after 4 cases SBRT.
Next step is to start SBRT as standard treatment off clinical
trial, along with other new technology including IMRT, VMAT,
and IGRT.
Question 1
Which of the following treatments can Windsor
Regional Hospital Cancer Program provide to treat
lung cancer?
A) 3D-CRT
B) IMRT/VMAT
C) IGRT
D) SBRT
E) All of the above
Question 2
What is the expected local control rate at 3 years for
stage 1 non-small cell lung cancer treated with SBRT in
LUSTRE trial?
A) 50-70%
B) 75%
C) 87.5%
D) 88%
E) 100%
Thank you!