Laboratoire de physique corpusculaire de Caen

RESEARCH

Nuclear science applications

PMRT

Radiotherapy modelling platform

The European Union and the Normandy Region subsidise the PMRT project

The purpose of the PMRT is to comprehensively collect the treatments applied (external radiotherapy with X-rays, protons and later hadrons) and the clinical results of these treatments, in order to develop models of tumour control and, above all, of induction of side effects.

The Laboratoire de Physique Corpusculaire de Caen (LPC-Caen) is a fundamental and applied research laboratory in nuclear and radiation physics. It consists of six research groups, including the Medical and Industrial Applications Group (GrAMI). GrAMI conducts research in the fields of measuring effective sections for hadrontherapy, dosimetry of ionising radiation and the study of the clinical effects of treatments using this ionising radiation (Radiotherapy Modelling Platform project, PMRT). The purpose of the PMRT is to collect exhaustively the treatments applied (external radiotherapy by X-rays, protons and later hadrons) and the clinical results of these treatments, so as to develop models of tumour control and especially of induction of side effects. The ultimate goal is to produce, for a new patient, a complete dashboard, for the radiotherapist oncologist, of the predictions (as well as their uncertainty) concerning the patient, knowing his clinical file and the treatment(s) envisaged.

The implementation of such a project has several aspects.

Firstly, a structured database of clinical data must be built. The LPC-Caen has been collaborating on this subject since 2015 with the Centre François Baclesse (CFB/Caen) and the Centre Paul Strauss (CPS/Stasbourg). The CPS has developed such a database on which we are currently working on methods of information extraction and analysis.
This database must then be enriched with initial metadata (images, contours, dosimetry, biological information). This step is part of the present project.
The means of extraction and anonymisation of all this information must be available. The LPC-Caen, in collaboration with the CFB, has set up a security pipeline process that guarantees this perfect anonymisation. This technology must be put into production at the WMC, both on structured clinical data and on imaging and biological metadata, both on current photon treatments and on proton treatments carried out at Cyclhad.
Finally, this information must be used to develop models of the effects (tumour control and complications) of ionising radiation, which is the aim of the project.

The first objective is to put into production the clinical collection on the structured database and the coupling of this data to the imaging and biological metadata by adapting the security pipeline so that it can process all of this information without restriction. Once in production, the database will be continuously populated as X-ray and proton processing proceeds. In the first year, it will be insufficient to produce convincing models.

We will take advantage of this phase to take up all the “standard models” of radiotherapy applicable to the treatments carried out in these two modalities, by readjusting these models in order to obtain their predictions, but also the uncertainty of these predictions, in a Bayesian approach which is at the heart of our inference process. We will also develop observational systems for toxicities that will provide early warning of unexpected changes in one treatment technique relative to another. This is the second objective of the PMRT programme.

The final objective is to develop more accurate and individualised models of clinical outcomes, knowing the initial treatment information. These models will exploit all the data collected and will be supported by a software architecture capable of supporting the diversity of treatments observed.

[This project is co-funded by the European Union and the Normandy Region to the tune of €177k for the period from 01/09/2018 to 31/08/2021].