gms | German Medical Science

48th Meeting of the Particle Therapy Co-Operative Group

Particle Therapy Co-Operative Group (PTCOG)

28.09. - 03.10.2009, Heidelberg

The application of Monte Carlo to ion beam therapy treatment planning

Meeting Abstract

  • K. Parodi - Heidelberg Ion Beam Therapy Center, Heidelberg, Germany
  • S. Brons - Heidelberg Ion Beam Therapy Center, Heidelberg, Germany
  • A. Mairani - Heidelberg Ion Beam Therapy Center, Heidelberg, Germany
  • F. Sommerer - Heidelberg Ion Beam Therapy Center, Heidelberg, Germany

PTCOG 48. Meeting of the Particle Therapy Co-Operative Group. Heidelberg, 28.09.-03.10.2009. Düsseldorf: German Medical Science GMS Publishing House; 2009. Doc09ptcog157

DOI: 10.3205/09ptcog157, URN: urn:nbn:de:0183-09ptcog1576

Published: September 24, 2009

© 2009 Parodi et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Purpose: To describe the application of Monte Carlo (MC) methods to provide basic input data and to support validation and improvement of Treatment Planning Systems (TPS) for accurate physical and biological dose calculations in ion beam therapy.

Material and methods: Clinical exploitation of the utmost dose conformality offered by scanned ion beams demands accurate determination and characterization of the individual pencil-like beams building up the treatment field. At present, clinical TPS can only rely on fast performing analytical pencil-beam algorithms. However, MC transport codes offer more powerful and flexible computational tools for detailed description of ion beam interactions in the beamline and the target, including the complex and heterogeneous patient tissue. Therefore, MC calculations based on the FLUKA code (Battistoni G, et al. In: Albrow M, Raja R. AIP Conference Proceeding; 2007; 896. p. 31-49., Fassō A, et al. CERN-2005-10. 2005.) have been extensively performed at the Heidelberg Ion Therapy Center (HIT) for manifold activities related to treatment planning, including (1) determination of the library of the synchrotron beam energies and foci (i.e., lateral widths at isocentre of the treatment unit), (2) calculation of the basic data to be input into the commercial TPS (Syngo PT Planning, Siemens), (3) forward re-calculation of physical and biological dose in water and the patient Computed Tomography (CT) data for TPS validation (Mairani A, et al Contribution to this conference.), (4) design and optimization of equipment for patient irradiation and quality assurance ( Rinaldi I, et al. contribution to this conference.).

Results: FLUKA-based MC calculations have provided the parameters of the accelerator library as well as the TPS basic input data (laterally integrated depth-dose curves and fragment spectra) which will be used for clinical operation at HIT. Besides, they have supported validation of the TPS pencil-beam algorithms as well as risk analysis studies. The very good agreement so far observed between MC calculations and measurements indicates that the FLUKA code is a valuable choice for transport of therapeutic proton and carbon ion beams. Examples of dedicated treatment planning applications as well as ongoing investigations aiming to promote further improvement of the TPS beam modeling for advanced ion beam therapy will be presented.

Conclusion and outlook: Despite the still too long computational times for inverse dose optimization and daily clinical use, MC methods are very valuable tools to support all the main aspects of scanned ion beam delivery and treatment planning, and we foresee that MC will play an increasing role in promoting high precision ion beam therapy.