[Quality assurance of radiotherapy in clinical research]

Quality assurance for radiotherapy of a clinical trial is an important step from the design of the clinical trial. A precise definition of quality assurance must be given in detail in the clinical protocol of the clinical trial. By its implementation, quality assurance allows a homogeneity of the clinical trial, which can lead to a reduction of the biases of results interpretation for the clinical trial. The complexity of the radiotherapy to be carried out within the framework of the clinical trial can induce a gradation for the radiotherapy quality assurance program of the trial. However, the following steps are always present and must be described either directly in the clinical protocol or in a specific chapter, radiotherapy quality assurance, of the clinical protocol. The detailed characteristics of the medical imaging required to prepare for the treatment, the delineation of the targets and organs at risk, the requirements related to the planning, the treatment itself, possibly including the positioning repositioning control images, of the patient. For the delineation and planning stages, it is common to set up benchmarking based on test cases (dummy run, dry run). Their validation makes it possible for the center to get credentials for the clinical trial. Some trials can provide for an additional quality assurance point, such End-to-End test for which the investigating center must carry out, according to the clinical protocol, the preparation, the planning, the treatment on an anthropomorphic test object containing models of targets, organs at risk as well as dosimeters. Quality assurance of radiotherapy in clinical research is an essential part to be taken into account from the design of the clinical study. The commitment of the investigating center in terms of human and material resources in compliance with the protocol and in the quality assurance of the trial constitute a guarantee of limitation of the biases for the study and its interpretation, facilitating the answer of the scientific question asked by the trial.