Towards ion beam therapy based on laser plasma accelerators

Abstract

Only few ten radiotherapy facilities worldwide provide ion beams, in spite of their physical advantage of better achievable tumor conformity of the dose compared to conventional photon beams. Since, mainly the large size and high costs hinder their wider spread, great efforts are ongoing to develop more compact ion therapy facilities. One promising approach for smaller facilities is the acceleration of ions on micrometre scale by high intensity lasers. Laser accelerators deliver pulsed beams with a low pulse repetition rate, but a high number of ions per pulse, broad energy spectra and high divergences. A clinical use of a laser based ion beam facility requires not only a laser accelerator providing beams of therapeutic quality, but also new approaches for beam transport, dosimetric control and tumor conformal dose delivery procedure together with the knowledge of the radiobiological effectiveness of laser-driven beams. Over the last decade research was mainly focused on protons and progress was achieved in all important challenges. Although currently the maximum proton energy is not yet high enough for patient irradiation, suggestions and solutions have been reported for compact beam transport and dose delivery procedures, respectively, as well as for precise dosimetric control. Radiobiological in vitro and in vivo studies show no indications of an altered biological effectiveness of laser-driven beams. Laser based facilities will hardly improve the availability of ion beams for patient treatment in the next decade. Nevertheless, there are possibilities for a need of laser based therapy facilities in future.

Ultra-High Dose Rate (FLASH) Radiotherapy: Silver Bullet or Fool's Gold?

“…Alternative concepts of producing 6-10 MV FLASH X-ray beams would be to use multiple synchronized linear accelerators or a powerful recirculating accelerator (74). Albeit large and expensive, a clinically available system for treating deep-seated tumors with FLASH-RT is with proton beams (75,76). Clinical proton beams have good depth penetration, are often electromagnetically steered, and can produce conformal dose distributions with a single to a few beams (65).…”

State-of-the-Art and Future Prospects of Ion Beam Therapy: Physical and Radiobiological Aspects

“…Ultrahigh dose rates are also discussed in the framework of laser generated particle beams, where ions are accelerated by shooting thin foils with extremely short (fs) laser pulses [177]. In line with the results reported above, Zlobinskaya et al [178] found no difference in the tumor growth response between conventional irradiation and pulsed proton irradiation of human tumor xenografts in nude mice.…”

Hadron Therapy Based on Laser Acceleration in the Plasma Channel Using Oxygen Ionization

“…First, laser accelerators should be created, which convey a characterized number of ions inside the restorative energy run with adequately steady and reproducible ion beam parameters. Second, a framework for beam transport and conveyance is required for cleaning the beam from undesired particles and for guaranteeing the beam energy, beam intensity, beam direction, and the field size to convey an endorsed dose to the patient [36].…”

“…The built-up dosimeters should be explored for similarity with laser-driven beams; for example, light emissions and high radiation pulses. On the other hand, important new dosimeters should be created, which most likely need more exertions as adjusting existing ones [36].…”