Dr. Jing Zeng, Medical Director at SCCA Proton Therapy, presents on what patient populations is a candidate for proton therapy.

1. Best Practices in Identifying
Proton-Appropriate Patients
Presented by Dr. Jing Zeng
Associate Professor, Department of Radiation Oncology, University of Washington School of Medicine
Medical Director, SCCA Proton Therapy Center
Radiation Oncologist, University of Washington Medical Center

2. Introduction
Protons are a form of radiation treatment that,
for a subset of patients, may provide a clinical benefit
when compared with standard radiotherapy.
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3. Finding the 3%
Your challenge: Proton
therapy is appropriate in only
3-10% of solid tumor cases.
But for that group,
there are many expected
clinical benefits.
How can
I make sure that
my patient is
getting the best
treatment plan?
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4. • Ability to apply higher therapeutic dosages, because
the beam delivers the most radiation at the tumor site,
reducing overall exposure
• Expected reduction in radiation-caused secondary cancers
- Particularly critical to young people and pediatric cases
- Important to anyone with long life expectancy
• Less radiation damage to nearby healthy tissue
- Particularly important in ocular, brain, lung and
breast cancers
• Clinical evidence to support fewer side effects compared
to X-rays in certain patients
Clinical Benefits
of Proton Therapy

5. So Why Only 3-10%?
• 30% of solid tumor cancer patients receive radiation (of any type)
• Protons are not generally applicable for metastasized cancers
– Half of the 60% are treated for palliative, versus curative, care
• Limited resource
• Cost
• Complexity of treatment planning and delivery
• Availability of proton centers
Of 100% of cancer cases …
60% of these are solid tumor cases
30% of these are suitable for radiation
3-10% of these are suitable for protons
Cases suitable
for proton therapy
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6. When Is Proton Therapy Appropriate?
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Will share infographic
section once final.

7. Additional
Challenges
for the 3-10% • Lack of access to a proton center
– Only 25 in the US (the SCCA Proton Therapy Center
is the only proton center in the PNW)
– Typical 5-day-a-week, 6-week schedule is logistically
difficult if the patient lives far away
• Insurance confusion
– Inconsistent coverage policies between payers
– Fully covered by Medicare
• May not be available in-network
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8. Proton Centers in the US
• 25 centers in operation,
11 under construction
• Centers at Mayo Clinic,
MD Anderson, Harvard and
Memorial Sloan Kettering
• More than 150,000 patients
treated worldwide
• Significant regional
variation in payer coverage
of protons
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SCCA Proton
Therapy Center
2013
Seattle, WA
1200 mi reach

9. The Solution to Access in the PNW
Seattle Cancer Care Alliance Proton Therapy Center is:
• A resource for the PNW medical community, offering innovative radiation treatments for solid tumor patients
• Part of the Seattle Cancer Care Alliance, which harnesses the collective brain power of three world-class
organizations to help people live longer, better and richer lives
• Located at UW Medicine’s Northwest Hospital & Medical Center
• Working closely with insurance companies and patients to develop
coverage solutions
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10. Who Can
Benefit
from
Proton
Treatment?
• Pediatric patients
• Those whose tumor is very close to vital organs
– Ocular cancers
– Lung and left breast (the heart is very sensitive to
radiation)
– CNS tumors
– Head and neck cancers
– Chondrosarcomas/chordomas
• Re-irradiation patients
• Those who have a long life expectancy after their disease
and are at risk for second malignancies
– Lymphomas
– Younger men with prostate cancer
– Women with breast cancer
• Those with genetic conditions that predispose them
to high toxicity when exposed to radiation
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11. Protons:
Where
Is the
Evidence?
• The greatest benefit of protons is in integral radiation
dose reduction.
– All radiation advances increase the targeting of the
tumor
– Takes decades to realize this benefit
• There is a lack of evidence for radiation treatment
industry-wide, not just for protons.
– Few long-term studies comparing modalities
– While long-term toxicity is expected to be reduced
(harder to measure), acute toxicity may be similar
(easier to measure)
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12. The best way to
minimize side effects,
and perhaps improve
outcomes, is to
eliminate any exposure
of healthy tissue to
treatment.
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13. 13
Protons in Pediatrics
• Radiation is of concern in children because:
– Higher chance of secondary cancers due to long
life expectancy post cancer
– Heightened sensitivity to radiation in children
• Protons can address these concerns:
– Ability to deliver an increased therapeutic dose
– Less harm to nearby tissue
– Ability to limit overall exposure
• Protons are standard of care for a variety of
pediatric solid tumors
– Medulloblastomas
– Pediatric CNS tumors

14. Pediatric Neuroblastoma Patient
Images represent a reduction in radiation to the abdomen, when using protons
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Protons Photons Protons Photons

15. Medulloblastoma:
Craniospinal Irradiation
Images represent a reduction in radiation to the entire chest and abdomen cavities, when using protons
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Protons Photons

16. Ocular Tumors Protons have been well established
in the management of ocular tumors,
specifically ocular melanomas.
Previously, specialized “dedicated eye”
facilities offered protons to patients with
these tumors.
The SCCA Proton Therapy Center is
a state-of-the-art, clinically-focused
facility that has a first-in-class ocular
treatment program. The standard course
of ocular treatment is five sessions.
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Protons Photons
Decrease in radiation exposure to underlying
brain tissue, when using protons

17. Breast Cancer There is increasing awareness that any
radiation dose to the heart, no matter how
small, can result in an increased
risk of major cardiac events during the
lifetime of a patient. The Darby paper,
a groundbreaking report in the New
England Journal of Medicine, reported
that any level of radiation delivered to the
heart in women with breast cancer is toxic.
For certain patients, protons can
significantly spare the heart while allowing
all critical regions to be treated.
We’re participating in an ongoing effort
sponsored by the Patient-Centered
Outcomes Research Institute (PCORI)
to test this question in a multi-center,
randomized trial.
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Protons Photons
Images represent a significant reduction in
radiation to the heart, when using protons

18. Head & Neck Cancer H&N cancer cure rates with radiation
therapy have been excellent for the past 30
years.
The focus has been on side-effect reduction:
• IMRT is a reflection of that evolution
• Proton therapy, with pencil beam
scanning, is another evolutionary step
It provides improved conformality of
the curative high-dose region and reduces
the low-dose bath.
This is a “win-win” for H&N patients
and represents the next step forward
from IMRT.
We are planning to participate in a
randomized trial of IMRT vs. protons
for H&N cancer.
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Protons Photons
Images represent a reduction in radiation
to the head and brain, when using protons

19. Collaborative
Treatment Planning
• Radiation
– IMRT
– Brachytherapy
– Stereotactic radiosurgery
– Gamma knife
– Proton therapy
– Neutrons
• Chemo
• Hormone therapy
• Immunotherapy
• Transplant
• Surgery
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The oncologists at Seattle Cancer Care Alliance
have expertise in all forms of cancer treatment.
Our aim is to find the best treatment for the
patient after considering all options.

20. 20
Clinical Review of
Treatment Options
If radiation is the chosen treatment, then what is
the best radiation approach?
• An independent cancer-site tumor board review of
treatment plans across modalities
• A consultation review with other cancer specialists
• A collaborative planning session and review with the
referring physician
• A comparison of the X-ray radiation treatment plan with
protons
• A joint recommendation to the patient in partnership with
the referring physician

21. 21
Selected Clinical Trials
Proton Beam Radiotherapy and Concurrent Chemotherapy for
Unresectable Stage III Non–Small Cell Lung Cancer: Final Results of a
Phase 2 Study
- by Joe Y. Chang et al. JAMA Oncol. August 20, 2017
Charged particle therapy versus photon therapy for paranasal sinus and
nasal cavity malignant diseases: a systematic review and meta-analysis
- by Samir H Patel et al. The Lancet, August 2014
Second Nonocular Tumors Among Survivors of Retinoblastoma Treated
with Contemporary Photon and Proton Radiotherapy
- by Roshan V. Sethi et al. Cancer January 1, 2014
Risk of Ischemic Heart Disease in Women after Radiotherapy for Breast
Cancer
- by Sarah C. Darby et al. N Engl J Med, March 14, 2013

22. Takeaway
Protons, in some cases,
offer substantial clinical
benefit, particularly in
reduction of secondary
cancers.
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1 2 3 4
The decision of whether
to use protons is a
collaborative effort with the
referring physician, the SCCA
oncology team and the patient.
We want to help you
identify the 3-10% of
patients for whom
protons may be a
consideration.
The SCCA Proton Therapy
Center is here to help
as a research, community
and clinical resource.

23. Thank You
Dr. Jing Zeng
jzeng13@uw.edu