medical requirements for ffag as proton beam sources jacques balosso, md, phd radiation oncologiste...
Post on 11-Jan-2016
228 Views
Preview:
TRANSCRIPT
Medical requirements for FFAG as proton beam sources
Jacques BALOSSO, MD, PhD
Radiation oncologiste
UJF / INSERM / ETOILE
FFAG 2007, April 12-17, 2007 Grenoble
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)
X-Rays Protons Carbone
Neutrons
RBE 1
RBE >> 1
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.
Indication for Indication for a fractionated a fractionated radiotherapy radiotherapy of RBE of RBE 1 1
Indication for Indication for particle particle therapy having therapy having an RBE >> 1an RBE >> 1S
urv
ival
Consequently …
• Protons indications are not limited
• Protons can, with the time, replace X-Rays
• 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
• 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?
top related