The Skandion clinic, plans for the use of particle beams for radiation

therapy in Swedenpresented by

Erik Grusell, medical radiation physicist

Dept of Hospital PhysicsUppsala University Hospital

”Akademiska Sjukhuset”Uppsala, Sweden

BACKGROUND

In the year 2003 48676 cancer cases were diagnosed – approximately twice as many as in the year 1970.

Half of all cancer cases will receive radiation treatment at some point.

Source: www.cancerfonden.se

Approximately half of the patients receiving radiation treatment receive a palliative treatment, intended to relieve symptoms such as pain. In these cases there is no hope of cure, so late side effects will not have time to manifest themselves.

The rest of the patients receive a treatment meant to cure the patient, which means to eradicate the tumor.

Patients receiving a curative treatment generally have a relatively long expected survival, which makes avoiding late side effects a concern.

Certain patients with benign tumors or some other diagnoses such as arterio-venous malformations in the brain can receive radiation treatment. These patients also have long expected survival times.

Minimizing irradiation of healthy tissue is of great importance for these patients.

Why protons?• Dose distribution advantage compared to conventional beams: x-rays and electrons

• Biological effect close to that of conventional beams

Why protons?• Dose distribution advantage compared to conventional beams: x-rays and electrons

• Biological effect close to that of conventional beams (in contrast to heavier ions)

Depth Dose Distributions

0 5 10 15 20 250

20

40

60

80

100

120

16 MeV elektrons

173 MeV protons

21 MV photons

Range (cm)

Rel

ativ

e do

se (

%)

Protons

Photons IMRT

Courtesy of Massachusetts General Hospital, Northeast Proton Therapy Center, Boston

Dose distribution medulloblastom

Protons vs carbon ions

Dose distributions are similar

Carbon ions are more densely ionisingThis gives a more effective cell kill

However, the possible clinicaladvantage of this is not proven

RBE = Relative Biological Efficiency

Factors that influence RBE

Radiation quality (LET)Radiation doseNumber of dose fractionsDose rateBiological systems or end point

Therapy

The Svedberg Laboratory (TSL)

1957 – 1973: 73 patients

1989 – 2007: 840 patients

180 MeV protons

Examples of intracranial targets (meningeomas) treated at TSL

Why protons?• Dose distribution advantage compared to conventional beams: x-rays and electrons

• Clinical results: Good local control and few adverse effects, but…

Very little of clinical evidence

The Swedish Particle Therapy Project (2001-2003)

• The number of patients in Sweden calculated to have a certain benefit with proton beam therapy is 2,200 – 2,500 per year.

• This figure corresponds to ~10 % of all cancer patients receiving radiotherapy.

• A national proton therapy facility in Uppsala built to treat 1000 patients per year would cost about 900 MSEK (2007 approximation) in total investment expenditures

• Design and construction would probably take 3 years (?) from start to treatment of the first

patient

SPTC final reportOctober 2003

In parallel with the SPTC project another particle therapy project was proposed at the Karolinska Institute in Stockholm [A Brahme et al. Nucl Instr & Meth B 184 (2001) 569-88]

This project was strongly focused on the potential benefits of light ions [A Brahme. Int J Rad Onc Biol Phys 58 (2004) 603-16]

If possible a facility combining proton and light ion beams shall be built

If a combination facility cannot be realized, a proton facility prepared for a future light ion extension shall be built

The facility shall be built on the principle of “shared governance – distributed competence”

The facility shall be located in Uppsala

Professional agreement was reached at a meeting in Göteborg, 9-10 november 2005:

July 2006The councils of the seven counties with university hospitals decided to form a

”Joint Authority of County Councils for Advanced Radiation Therapy”

with the aim of building a national particle therapy facility according to the professional agreement

2006

“Prequalification to tender for supply and installation of a complete particle (protons & ions) therapy facility under a turnkey contract”

Evaluated in November 2006 The Joint Authority decided to build a

proton facility with land area reserved for a future light-ion facility

Specifications for the Skandion Clinic

• A turnkey facility with high uptime (>95%)

• The facility shall meet all national and international safety standards including CE-marking

• Active scanning with intensity modulated proton therapy (IMPT) is required in every treatment room

• Isocentric gantries

• Proton range and field sizes enabling treatment of all target location

• A minimum treatment capacity per year of 1000 patients. Possibility to increase the treatment capacity to 2500 patients by increasing the working hours

Beam flattening: Passive scattering in metal foils Energy loss, beam loss, long distance

Collimator

Collimator

Dual foil technique (Grusell et al 1994)

The accelerator produces a narrow pencil beam

Pencil beam

Active scanning

Image from Kraft and Weber, GSI

Scanning vs. passive scattering

+ Better dose conformity+ Less activation and neutron production+ No beam specific modifiers (filters, collimators,

etc.)+ Large field sizes+ No energy losses, longer range

- More sensitive to patient and organ movements (gating, tracking, rescanning needed?)

- More complex control system

Centres with proton or light ion therapy 2008

Protons

Light ions

2008- 2012 Tender for supply and installation of a

complete proton therapy facility under a turnkey contract

Tender period by the end of 2008

Manufacturers of proton or combined proton-ion radiation therapy facilities:

Ion Beam Applications (Belgium)Varian (USA and Germany)Siemens (USA and Germany)Hitachi (Japan)Mitsubishi (Japan)Optivus (USA)

The Skandion Clinic

IBA Isocentric Gantry

Diameter ~11m

Treatment room - Mitsubishi

Location of the Skandion Clinic

SkandionSkandion

University University HospitalHospital

Conclusions

• A national particle therapy centre will be built in Sweden - The Skandion Clinic in Uppsala

• It will be owned and operated by the seven university hospital counties together

• This is the first time in Sweden that a large scale health care investment is managed in collaboration between all the university hospitals