Transcript Medical requirements for FFAG as proton beam sources

FFAG 2007, April 12-17, 2007 Grenoble
Medical requirements for FFAG
as proton beam sources
Jacques BALOSSO, MD, PhD
Radiation oncologiste
UJF / INSERM / ETOILE
Plan
• Why to use protons in radiotherapy ?
• What kind of tumors are presently treated
by protons ?
• What kind of tumors would be treated by
widely available proton beams?
• Requirement for a medical proton source
• Prospective for a radiotherapy of the future
• Why to use protons in radiotherapy ?
• What kind of tumors are presently treated
by protons ?
• What kind of tumors would be treated by
widely available proton beams?
• Requirement for a medical proton source
• Prospective for a radiotherapy of the future
The protons Bragg peak
The 200 MeV Bragg peak of the CPO (Orsay, France)
The protons Spread Out Bragg
Peak (SOBP)
The inside structure of the proton SOBP
Comparison of the « efficient » dose according to the depth
for photons, a proton SOPB and a carbon ion SOBP. (GSI,
Darmstadt, Germany)
PSI Villigen
PSI Villigen
PSI Villigen
PSI Villigen
Comparison of the « efficient » dose according to the depth
for photons, a proton SOPB and a carbon ion SOBP. (GSI,
Darmstadt, Germany)
RBE  1
X-Rays
Protons
RBE >> 1
Carbone
Neutrons
Protons and Carbon ions are not
offering the same advantages
• Protons are representing a crude and
important ballistic improvement for any
type of radiotherapy…
providing they are affordable !
• Carbones are an innovative kind of
radiations with particular radiobiological
properties suitable for certain
indications only.
Survival
Indication for
a fractionated
radiotherapy
of RBE  1
Indication for
particle
therapy having
an RBE >> 1
Consequently …
• Protons indications are not limited
• Protons can, with the time, replace XRays
• Carbon ions should have a definitive
and limited number of indications
• These indications are a number of
therapeutic spots present in different
groups of tumors.
• Why to use protons in radiotherapy ?
• What kind of tumors are presently
treated by protons ?
• What kind of tumors would be treated by
widely available proton beams?
• Requirement for a medical proton source
• Prospective for a radiotherapy of the future
Indications for protontherapy in Loma
Linda (1)
• Brain and spinal cord
– Isolated brain metastases
– Pituitary adenomas
– Arteriovenous malformations (AVMs)
• Base of skull
– Meningiomas
– Acoustic neuromas
– Chordomas and chondrosarcomas
• Eye
– Uveal melanomas
In red: indications treated in France
Indications for protontherapy in Loma
Linda (2)
Head and neck
– Nasopharynx
– Oropharynx (locally advanced)
• Chest and abdomen
– Medically inoperable non-small-cell lung cancer
– Chordomas and chondrosarcomas
• Pelvis
– Prostate
– Chordomas and chondrosarcomas
• Tumors in children
– Brain
– Orbital and ocular tumors
– Sarcomas of the base of skull and spine
Uvea melanoma treated by protons
Chondrosarcoma of the skull base
Chordoma
Meningioma
• Why to use protons in radiotherapy ?
• What kind of tumors are presently treated
by protons ?
• What kind of tumors would be treated
by widely available proton beams?
• Requirement for a medical proton source
• Prospective for a radiotherapy of the future
Indications for protontherapy in Loma
Linda (1)
• Brain and spinal cord
– Isolated brain metastases +++
– Pituitary adenomas
– Arteriovenous malformations (AVMs)
• Base of skull
– Meningiomas
– Acoustic neuromas
– Chordomas and chondrosarcomas
• Eye
– Uveal melanomas
In red: indications treated in France
Indications for protontherapy in Loma
Linda (2)
Head and neck
– Nasopharynx +++
– Oropharynx (locally advanced)
• Chest and abdomen
– Medically inoperable non-small-cell lung cancer +++
– Chordomas and chondrosarcomas
• Pelvis
– Prostate +++
– Chordomas and chondrosarcomas
• Tumors in children
– Brain
– Orbital and ocular tumors
– Sarcomas of the base of skull and spine
• Why to use protons in radiotherapy ?
• What kind of tumors are presently treated
by protons ?
• What kind of tumors would be treated by
widely available proton beams?
• Requirement for a medical proton
source
• Prospective for a radiotherapy of the future
Technical requirements
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Depth: 2 to 30 cm in water
Size: at least 10 x 10 cm up to 20 x 20
Dose rate: at least one Gy / min / liter
Precision of size & position: 1 mm
Precision of the dose: +/- 2 to 3%
Operability: > 97%
Session time: < 30 min
Beam control: active +++ (rapid change of
energy ??) better than passive
Exemple of a single proton beam
Exemple of the set-up with a gantry
• Why to use protons in radiotherapy ?
• What kind of tumors are presently treated
by protons ?
• What kind of tumors would be treated by
widely available proton beams?
• Requirement for a medical proton source
• Prospective for a radiotherapy of the
future
Toward the future of radiotherapy
• 100% hadrontherapy:
– with 95% proton
– and 5% light-ions (carbon…)
• High precision and small volume of early
diagnozed tumors
• Few sessions of >> « 2 Gy »
• Fast shot RT to reduce immobilization and to
favor precision of moving target treatment (lung,
lever, prostate…)
• About 5000 treatments / 106 inhabitants per
year in 20 years
Open questions
• What type of machine for the generalized
availability of protons ?
• What are the radiobiological characteristic of
very high dose rates ?
• What could be the organization and the
economical conditions of very short but
highly sophisticated treatments ?
• Could FFAG be an answer?