Transcript Stereotactic Body Radiotherapy - Windsor Cancer Research Group

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!