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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.
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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) Knee and Foot Support (both indexed) Arm Support
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 go-ahead 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
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 4-14 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 3D-CRT, if necessary.
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.
1st 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%