# Presentation: 897034

## Protons for Cancer Therapy & Imaging

- Steve Peggs, BNL

## Summary – RCMS

- 1) US medical centers are now convinced that proton therapy works, and that there is a viable business model
- 2) A new wave of proton therapy facility construction has begun
- 3) Structural financial issues:
- 		finding a prime contractor
- 		finding a major medical center
- 		BNL seeks partners for RCMS
- 4) Structural technical issues:
- 		developing the virtues of the RCMS – read the CDR
- 		slow/fast extraction
- 		patient treatment/FDA/control system
- 		R&D prototyping, eg main magnet/vacuum chamber

## The story so far

- 1992
- TM-1774 offers a critique of the LL synchrotron, and suggests:
-    1) strong focusing
-    2) rapid cycling, fast extraction
-    3) high energy inject. (15 MeV?)
- 1999
- U. Penn (Lockyer) contacts BNL
- (Peggs)
- 2003
- “Conceptual Design of the Rapid
- Cycling Medical Synchrotron”
- + Cost & Schedule analysis

## “RCMS Conceptual Design Report”, &

- “RCMS Conceptual Design Report”, &
- Cost & (3 year) Schedule, exist

- ... but BNL faces structural
- issues, in competition with
- IBA, Siemens, Hitachi, ....

## Rapid Cycling Medical Synchrotron 

- the second generation

- Tandem
- injector (AES)

- Synchrotron
- accelerator

- Research
- Room lines

- Vertical
- fixed line

- Eye
- line

- Horizontal
- fixed line

- Gantry 1
- (ACCEL)

## Rapid Cycling Medical Synchrotron 

- Rapid Cycling Medical Synchrotron
- the second generation

- Tandem pre-
- injector (AES)

- Synchrotron
- accelerator

- Research room line

- Horizontal &
- eye fixed lines

- Gantries
- (ACCEL)

## The medical case for protons

- (versus X-rays in IMRT)

## The ideal depth-dose distribution?

- Depth

- Dose

- Protons come
- closest to the ideal

## 3 patched, intensity

- modulated fields....

## Compare protons with photons – 1

- Photons

- Protons

- Photons (X-rays) do NOT “stop” at a well defined boundary

## Compare protons with photons – 2

- IMRT Photons

- Protons

- Multiple fields (angles): with PROTONS
- 	- the “spine” is better protected
- 	- dose to surrounding normal tissue is INTRINSICALLY much less

## The business model for protons

- the wave is (finally) here!

## Operating & de-commissoned facilities 

- Operating & de-commissoned facilities

- USA

- Japan

- Volume
- leaders

## Proposed new facilities (July 03)

- U. Penn will very soon be on this “confirmed” list

## The U. Penn site

**Active discussions also at:**
** ****- Karolinska (Sweden)**
** ****- Sydney (Australia)**
** ****- TERA sites (Europe)**
** ****- Sloan Kettering (USA)**
** ****- Columbia-Presbyterian**
** ****- Chicagoland ?**

## Structural issues

- financial & technical, for BNL and/or FNAL

## Structural issues – financial

- 1) DoE regulations prevent BNL and/or FNAL from being a prime contractor.  National labs:
- 	- cannot compete in the marketplace
- 	- cannot take financial risk (can't raise capital or be bonded)
- 2) In the US environment
- 	- a major medical center MUST lead, not follow, a hadron
- 		therapy project (FNAL learned this in 1992)
- 	- there is little apparent interest in light ions or neutrons
- 3) BNL seeks a third party – FNAL, Siemens, ... – to get the
- 	RCMS built
- 4) DoE regs also explicitly require BNL/FNAL to be equally available to all potential RFP responders.

## Structural issues – technical

- 1) No time, here, to go into all the technical virtues of the RCMS
- 	- please read the CDR!
- 2) Slow/fast extraction in 3D scanning
- 	- some say fast extraction can't scan fast enough (not true:
- 		eg see TNS paper)
- 	- others says slow extraction has intrinsic risks of dumping
- 		much beam into the patient (only slow slow scans are safe?)
- 3) The Patient Treatment/FDA/Control System challenge is huge
- 	- for Hitachi & Siemens more than IBA (& Optivus)
- 4) The ideal next (technical) step for RCMS would be to do some
- 	R&D prototyping on the main magnet/vacuum chamber system

## Summary – RCMS

- 1) US medical centers are now convinced that proton therapy works, and that there is a viable business model
- 2) A new wave of proton therapy facility construction has begun
- 3) Structural financial issues:
- 		finding a prime contractor
- 		finding a major medical center
- 		BNL seeks partners for RCMS
- 4) Structural technical issues:
- 		developing the virtues of the RCMS – read the CDR
- 		slow/fast extraction
- 		patient treatment/FDA/control system
- 		R&D prototyping, eg main magnet/vacuum chamber

## Proton Computed Tomography

- (proton movies ~20 GeV not discussed here)

## proton Computed Tomography (pCT)

**Brookhaven National Laboratory**
- 	beam tests, tracking detectors,
- 	calorimeter, simulation
**Loma Linda University Medical Center**
- 	project coordination, calorimeter,
- 	readout/DAQ, beam tests, simulation
**Santa Cruz Institute for Particle Physics**
- 	tracking detectors, readout/DAQ,
- 	simulation
**Stony Brook University**
- 	tomographic reconstruction

## NEED: “high” dose XCT gets planning wrong

## NEW: silicon detector technology defeats blurring!

- Historically, proton radiography
- was rejected because multiple
- scattering made blurry images

- Modern detectors make
- sharp images through
- PROTON-BY-PROTON
- knowledge of incoming
- and outgoing displacements
- and angles

## Proton Computed Tomography camera

**Proton**
**Gantry**

**Tracking**

- Proton computed tomography:
- Take multiple projection images, as the gantry circulates around the patient
- Camera:
- 4 silicon detector planes +
- 1 energy calorimeter

**Notes:**
Computed tomography (CT) images of the patient provide the basic data for the treatment planning program.
CT data are used to define the position of the target and of critical normal tissues and to quantify inhomogeneities in the path of each proton beam.
The CT images provide 2D photon attenuation data which can be used to derive electron density information relative to water. For proton therapy, these electron density values have to be converted to stopping power relative to water.

## The PSI therapy gantry, with 

- The PSI therapy gantry, with
- early prototype camera in place

## The pCT collaboration seeks NIH funding

- to build and test a scaled prototype (red)
- and then a final system (black)

## Proton CT Funding Approach

- Research and Development
- NIH R01 grant or multiple R21 grants
- Implementation and Commissioning
- DOE and/or DOD
- External funding organization (e.g., BV)

- NIH application: Specific Aims

- 1: Design & build small proton-by-proton detector
- 2: Develop reconstruction algorithms based on simulated data sets
- 3: Measure radiography data with different phantoms
- 4: reconstruct & validate performance of detector & reconstruction

## Summary – Proton Imaging

- 1) proton Computed Tomography is driven by proton therapy needs, but has a much broader potential
- 		- lower dose
- 		- more accurate
- 2) Proton-by-proton pCT is enabled by tech transfer from high energy and nuclear physics experiments (silicon micro-detectors)
- 3) There is also great potential in making "CT movies" of periodic
- 	THICK mechanical systems
- 		- auto engines, ...