Radiation therapy is a crucial modality to treat cancer patients.
In particular, due to the improved depth-dose characteristics of charged particles, proton therapy enables to maximise the dose to the tumour while sparing the surrounding tissue, and is therefore the preferred treatment modality for example for pediatric patients.
Anatomical changes in the patient such as weight gain/loss or changes in nasal fillings might however degrade the proton therapy treatment, and thorough verification is crucial.
As such, in this collaborative project between ETH, PSI and CHUV, a dedicated scanner has been developed with the aim to verify or adapt the treatment.
This PETITION (PET for InTensive care units and Innovative protON therapy) scanner operates on the basis of positron emission tomography (PET):
While the protons are traversing the patient, due to nuclear interactions, positrons are generated, annihilate with electrons, and back-to-back photons are emitted which are then recorded by the PETITION scanner. The PETITION scanner is a dedicated system, which can be mounted directly on the patient couch, and could record PET images directly before, during or after treatment.
In this talk, first the basics of proton therapy and PET are explained.
Then, the PETITION scanner for proton therapy is demonstrated in more detail.
Finally, starting from simulations up to phantom measurements, two potential applications of the scanner, namely biological adaption and verification of the proton therapy treatment, are highlighted.