Frontiers in Oncology (Jun 2021)

Monitoring Carbon Ion Beams Transverse Position Detecting Charged Secondary Fragments: Results From Patient Treatment Performed at CNAO

  • Marco Toppi,
  • Marco Toppi,
  • Guido Baroni,
  • Giuseppe Battistoni,
  • Maria Giuseppina Bisogni,
  • Maria Giuseppina Bisogni,
  • Piergiorgio Cerello,
  • Mario Ciocca,
  • Patrizia De Maria,
  • Micol De Simoni,
  • Micol De Simoni,
  • Marco Donetti,
  • Yunsheng Dong,
  • Yunsheng Dong,
  • Alessia Embriaco,
  • Veronica Ferrero,
  • Elisa Fiorina,
  • Elisa Fiorina,
  • Marta Fischetti,
  • Marta Fischetti,
  • Gaia Franciosini,
  • Gaia Franciosini,
  • Aafke Christine Kraan,
  • Carmela Luongo,
  • Carmela Luongo,
  • Etesam Malekzadeh,
  • Marco Magi,
  • Carlo Mancini-Terracciano,
  • Carlo Mancini-Terracciano,
  • Michela Marafini,
  • Michela Marafini,
  • Ilaria Mattei,
  • Enrico Mazzoni,
  • Riccardo Mirabelli,
  • Riccardo Mirabelli,
  • Riccardo Mirabelli,
  • Alfredo Mirandola,
  • Matteo Morrocchi,
  • Matteo Morrocchi,
  • Silvia Muraro,
  • Vincenzo Patera,
  • Vincenzo Patera,
  • Vincenzo Patera,
  • Francesco Pennazio,
  • Angelo Schiavi,
  • Angelo Schiavi,
  • Adalberto Sciubba,
  • Adalberto Sciubba,
  • Adalberto Sciubba,
  • Elena Solfaroli-Camillocci,
  • Elena Solfaroli-Camillocci,
  • Elena Solfaroli-Camillocci,
  • Giancarlo Sportelli,
  • Giancarlo Sportelli,
  • Sara Tampellini,
  • Giacomo Traini,
  • Giacomo Traini,
  • Serena Marta Valle,
  • Barbara Vischioni,
  • Viviana Vitolo,
  • Alessio Sarti,
  • Alessio Sarti,
  • Alessio Sarti

DOI
https://doi.org/10.3389/fonc.2021.601784
Journal volume & issue
Vol. 11

Abstract

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Particle therapy in which deep seated tumours are treated using 12C ions (Carbon Ions RadioTherapy or CIRT) exploits the high conformity in the dose release, the high relative biological effectiveness and low oxygen enhancement ratio of such projectiles. The advantages of CIRT are driving a rapid increase in the number of centres that are trying to implement such technique. To fully profit from the ballistic precision achievable in delivering the dose to the target volume an online range verification system would be needed, but currently missing. The 12C ions beams range could only be monitored by looking at the secondary radiation emitted by the primary beam interaction with the patient tissues and no technical solution capable of the needed precision has been adopted in the clinical centres yet. The detection of charged secondary fragments, mainly protons, emitted by the patient is a promising approach, and is currently being explored in clinical trials at CNAO. Charged particles are easy to detect and can be back-tracked to the emission point with high efficiency in an almost background-free environment. These fragments are the product of projectiles fragmentation, and are hence mainly produced along the beam path inside the patient. This experimental signature can be used to monitor the beam position in the plane orthogonal to its flight direction, providing an online feedback to the beam transverse position monitor chambers used in the clinical centres. This information could be used to cross-check, validate and calibrate, whenever needed, the information provided by the ion chambers already implemented in most clinical centres as beam control detectors. In this paper we study the feasibility of such strategy in the clinical routine, analysing the data collected during the clinical trial performed at the CNAO facility on patients treated using 12C ions and monitored using the Dose Profiler (DP) detector developed within the INSIDE project. On the basis of the data collected monitoring three patients, the technique potential and limitations will be discussed.

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