As an alternative modality to conventional radiotherapy, electrons with energies above 50 MeV penetrate deeply into tissue, where the dose can be absorbed within a tumour volume with a relatively small penumbra. We investigate the physical properties of VHEEs and review the state-of-the-art in treatment planning and dosimetry. We discuss the advantages of using a laser wakefield accelerator (LWFA) and present the characteristic features of the electron bunch produced by the LWFA and compare them with that from a conventional linear accelerator.
Monte Carlo simulation experiments have shown that very high energy electrons (VHEE), 150-250 MeV, have potential
advantages in prostate cancer treatment over currently available electrons, photon and proton beam treatment. Small
diameter VHEE beamlets can be scanned, thereby producing a finer resolution intensity modulated treatment than
photon beams. VHEE beams may be delivered with greater precision and accelerators may be constructed at
significantly lower cost than proton beams. A VHEE accelerator may be optimally designed using laser-plasma
technology. If the accelerator is constructed to additionally produce low energy photon beams along with VHEE, real
time imaging, bioprobing, and dose enhancement may be performed simultaneously. This paper describes a Monte Carlo
experiment, using the parameters of the electron beam from the UCLA laser-plasma wakefield accelerator, whereby dose
distributions on a human prostate are generated. The resulting dose distributions of the very high energy electrons are
shown to be comparable to photon beam dose distributions. This simple experiment illustrates that the nature of the dose
distribution of electrons is comparable to that of photons. However, the main advantage of electrons over photons and
protons lies in the delivery and manipulation of electrons, rather than the nature of the dose distribution. This paper
describes the radiation dose delivery of electrons employing technologies currently in exploration and evaluates potential
benefits as compared with currently available photon and protons beams in the treatment of prostate and other cancers,
commonly treated with radiation.