Scanned Carbon Pencil Beams for Tumor Therapy

Journal Article · Tue Mar 10 04:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3120068· OSTI ID:21289567

Gemmel, A; Saito, N; Chaudhri, N; Luechtenborg, R; Schardt, D; Bert, Ch ^[1]; Rietzel, E ^[1]

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1. Gesellschaft fuer Schwerionenforschung mbH, Planckstr. 1, 64291 Darmstadt (Germany)

At GSI a fully active beam application has been developed for tumor therapy with carbon ions. In this so-called rasterscan system the tumor volume is typically split into {approx}60 slices of iso-energies taken from a list of 252 energies ranging from {approx}90-430 MeV/u(range: 1.8-30.7 cm). The energies can be combined with variable beam diameters and intensities. For each iso-energy slice beam is requested from the synchrotron and delivered as a narrow pencil beam (beam's full width at half maximum 3-10 mm). For lateral target coverage this pencil beam is deflected to several hundreds of grid positions per iso-energy slice by orthogonal dipole magnets. At each grid position an optimized number of particles is deposited intensity-controlled, i.e. ionization chambers monitor the dose deposition and trigger deflection to the next grid position once the required dose level is achieved. This method allows intensity-modulated treatment fields necessary to deposit a uniform biological effective dose. Additionally, it allows for simultaneous optimization of multiple fields that allow better sparing of organs at risk partially or fully surrounded by the tumor. Scanned beam delivery facilitates target conformal and homogeneous dose delivery for stationary targets. For tumors located in the head and neck as well as tumors in the pelvic region very promising results were achieved in the carbon therapy pilot project started at GSI in 1993. A comparable project is conducted at Paul-Scherrer-Institut (PSI) in Switzerland with a scanned proton beam. One of the current research topics is the treatment of moving targets such as lung tumors. Scanned beam delivery requires but also offers possibilities to conformably irradiate moving target sites.

• OSTI ID: 21289567
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1099; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BEAM MONITORING
BEAM TRANSPORT
CARBON IONS
DOSES
ION BEAMS
IONIZATION CHAMBERS
MEV RANGE
NEOPLASMS
OPTIMIZATION
PATIENTS
PROTON BEAMS
RADIOTHERAPY
SWISS ORGANIZATIONS
SYNCHROTRONS