[Survey by SFRO, SNRO and AFPPE about the evolution of the radiation therapist profession in France]. / Enquête SFRO­SNRO­AFPPE sur l'évolution du métier de manipulateur exerçant en radiothérapie en France.

PURPOSE: As part of the multidisciplinary team, radiation therapists are in charge of elements of treatment preparation and delivery of radiotherapy to cancer patients. Helping scientific and technological improvements, more and more patients with cancer were treated with radiotherapy including hypofractionnated radiotherapy, that explain the increase of demands on services. The professional impacted by this increase of demands are radiation oncologists and medical physicists. The opportunity to push forward the radiation therapist's competencies appears with the possibility to shift them some tasks. In this context, a first work was performed with objectives to have an overview of the tasks shifted to radiation therapists in France, the tasks that they could perform but also to evaluate some criteria of job satisfaction. MATERIAL AND METHODS: The committee of "new status and value of status" including six radiation oncologists (the French society of radiation oncology [SFRO] et national union of radiation oncologists [SNRO]) and six radiation therapists committee members of the French association of radiation therapists (AFPPE), built a questionnaire including three parts: demographic characteristics, tasks shifted and job satisfaction criteria. In total, the questionnaire included 19 questions and 24 items assessed with a four point-Likert scale (ranging from "completely disagree" to "completely agree"). This survey, formatting with google form, was tested by the committee members and the final version was sent to the SFRO, AFPPE and SNRO members, before being disseminated on the social networks. RESULTS: From November 18th 2022 to December 31st 2022, 492 responses were received (response rate=18.3%): 55 % of the respondents had at least 11 years of experience in radiotherapy. The respondents worked in different type of health facilities (36 % in specialized cancer centres, 19.5 % in private centers, 17.5% in university and general hospital, 10.2% in general hospital). More than » of the respondents had a teaching lecturer activity, 20% had a management team activity and a research activity for 18%. Less than 10% of the respondents had another degree than that of radiation therapist: university degree (n=27), degree in dosimetry (n=11) and master (n=3). More than 76% would like to be trained and to have access to the advanced practice, more than 50% would like expend competencies with a university degree, 30% with a master and 67% would like to participate in research. Forty-two percent of the respondents were involved in a task shifting (excluding decree relating to acts and activities carried out by radiation therapists) and among the radiation therapists non-involved, 63% would be interested in being. Regarding job satisfaction, 53% of the respondents were satisfied with their job and their salary and 68% believed that their job occupation is in line with their professional aspirations. More than 2/3 of the respondents described a significant workload and mental load, 53% thought to have time for their patient care and 70% felt some organisational difficulties. CONCLUSION: This survey shows: (i) A significant involvement of radiation therapists in the task shifting; (ii) A very strong demand for career development, in particular with existing degrees or to be created degree such as advanced practice; and (iii) The need to reinforce a job satisfaction for almost the half of the respondents, linked to a workload, a mental load and some organisational difficulties.

[Radiation therapists shortage in France: Organizational consequences and difficulties in deploying new missions and/or tasks delegation]. / Métier de manipulateur en radiothérapie en tension en France : conséquences organisationnelles et difficultés à déployer de nouvelles missions et/ou délégation de tâches.

PURPOSE: Radiation therapists shortage has been evaluated at national level in France, specifically in oncology radiotherapy, in terms of: (i) organizational adaptations, (ii) impact on patients care, and (iii) difficulties in deploying new missions and/or tasks delegation. MATERIALS AND METHODS: French professional organisations representing radiation therapists - SFRO, SNRO and AFPPE - sent their members a national survey (ten questions on 32 items). RESULTS: From 18 November 2022 to 31 December 2022, 55 responses were received (response rate: 31%) from radiotherapy managers or department heads; 51% had a structure comprising three to five treatment rooms (receiving 500 to 1000 patients per year [36%], or 1500 to 2000 patients per year [33%]). Activities performed were intensity-modulated radiotherapy (100%), stereotaxic radiotherapy (85%), brachytherapy (40%), adaptive radiotherapy (34%). These structures described consequences in closing machine time for 25% of them (reduction of the hourly volume greater than 10% in 57%) with the following consequences in the last 6 months: (i) an extension of the period of medical care (78%), a closing of one or more accelerators (50%) and the development of moderate hypofractionation scheme or extreme hypofractionation (50%). In current functioning, linear accelerators can deliver treatments with a team of two radiation therapists per room for a short day (43%) or two to four radiation therapists per room teams for a long day (40%). During the last 6 months, there has been a 10% increase in linear accelerators operating with a single team. (ii) regarding treatment planning: 16.4% reported a decrease in the opening amplitude (less than 20% in 44% of cases, from 20 to 50% in 33 % of cases). The initial scheduling of appointments for radiotherapy sessions was carried out by radiation therapists in 84% of the departments in current functioning (0.1 to 1 FTE dedicated to this activity in 62% of the departments). Over the last 6 months, there has been a clear reduction in the number of dedicated FTEs: [FTE=0.1 to 1]=-8%; [FTE=0]=+7%. (ii) Regarding tasks delegation (excluding the decree on acts and activities carried out by the radiation therapist): organ at risk delineation is partially performed by radiation therapist in 26% of the centres; caregiver support time in 78% (56% totally or 22% partially). This activity has been reduced by 42%. Seventy-five percent of departments want to develop new techniques, patient-centered approaches (44%), implement task delegation (organ at risk delineation: 58%; weekly consultations: 67%; positioning imaging validation: 71%), and 78% of departments are interested in developing advanced radiotherapy practice. However, the number of radiation therapists is considered insufficient in their implementation in 76% of cases (one to two FTE missing for 72% of structures). CONCLUSION: This survey shows a significant impact of radiation therapist shortage in radiotherapy oncology care (treatment delays, access to caregiver support time, workload on treatment teams), and represents a major obstacle to the development of radiotherapy structures.

RadioTransNet, Radiotherapy Translational and Preclinical Research Network: Results from the dedicated French cancer institute (INCa) call for projects.

PURPOSE: The RadioTransNet project is a French initiative structuring preclinical and translational research in radiation therapy for cancer at national level. The network's activities are organized around four chosen priorities, which are: target definition, normal tissue, combined treatments and dose modelling. The subtargets linked to these four major priorities are unlimited. They include all aspects associated with fundamental radiobiology, preclinical studies, imaging, medical physics research and transversal components clearly related to these scientific areas, such as medical oncology, radio-diagnostics, nuclear medicine and cost-effectiveness considerations. METHOD: During its first phase of activity, four workshops following the consensus conference model and based on scientific and medical state of the art in radiotherapy and radiobiology were organized on the four above-mentioned objectives to identify key points. Then a road map has been defined and served as the basis for the opening in 2022 of a dedicated call, SEQ-RTH22, proposed by the French cancer national institute (INCa). RESULTS: Four research projects submitted by RadioTransNet partners have been selected to be supported by INCa: the first by Professor Anne Laprie from Oncopole Claudius-Regaud and Inserm ToNic in Toulouse on neurocognition and health after pediatric irradiation, the second submitted by Fabien Milliat from IRSN aims to study decryption and targeting of endothelial cell-immune cells interactions to limit radiation-induced intestinal toxicity, the third project, submitted by Yolanda Prezado from institut Curie-CNRS on proton minibeam radiotherapy as a new approach to reduce toxicity, and the latest project proposed by R. de Crevoisier from centre Eugène-Marquis in Rennes on predictive multiscale models of head and neck radiotoxicity induced for optimized personalized radiation therapy. Topics of each of these projects are presented here. CONCLUSION: RadioTransNet project has been launched in 2018, supported by INCa, in order to structure and promote preclinical research in oncology radiotherapy and to favor collaboration between the actors of this research. INCa relied on RadioTransNet initiatives and activities, resulting in the opening of dedicated call for projects. Beyond its first main goals, RadioTransNet network is able to help to fund the human and technical resources necessary to conduct optimal translational and preclinical research in radiation oncology.

RadioTransNet: Preclinical research network coordinated at the SFRO and SFPM.

The RadioTransNet programme launched under the auspices of French societies for radiation oncology (SFRO) and medical physics (SFPM) was approved by the French national cancer institute (INCa) in December 2018 and is dedicated to proposing a relevant national and transversal structure for preclinical research including translational research in radiation oncology with well-defined priority areas of research. Its activities, coordinated by a scientific committee that includes radiation oncologists, medical physicists, academic biologists, are structured around several main areas, i.e.: target volume definition, interaction of radiation with normal tissues, combined treatments and modern dose calculation approaches. Four work packages have been created in these areas and are associated with other objectives pertaining to fundamental radiobiology, early implementation of new drugs in a preclinical setting, contribution of imaging in this task, research in medical physics including transversal components such as medical oncology, radiology, nuclear medicine and also cost/efficiency evaluation. All these tasks will be included in a national network that uses the complementary expertise provided by partners involved in the scheme. Calls for proposals will be selected by the scientific council to be submitted to INCa and the various academic associations to obtain funding for the human and technical resources required to conduct under optimal conditions projects in preclinical and translational research in radiation-oncology.

[Radiation-oncology horizon 2030: From microbiota to plasma laser]. / Oncologie-radiothérapie horizon 2030 : du microbiote au laser plasma.

Advances in physical, technological and biological fields have made radiation oncology a discipline in continual evolution. New current research areas could be implemented in the clinic in the near future. In this review in the form of several interviews, various promising themes for our specialty are described such as the gut microbiota, tumor organoids (or avatar), artificial intelligence, connected therapies, nanotechnologies and plasma laser. The individual prediction of the best therapeutic index combined with the integration of new technologies will ideally allow highly personalized treatment of patients receiving radiation therapy.

[RadioTransNet, the French network for preclinical research in oncological radiotherapy]. / RadioTransNet, le réseau national de radiothérapie oncologique préclinique.

The ambition of the RADIOTRANSNET network, launched by the INCa at the end of 2018, is to create a French research consortium dedicated to preclinical radiotherapy to foster scientific and clinical interactions at the interface of radiotherapy and radiobiology, and to identify research priorities dedicated to innovation in radiotherapy. The activities of the network are organized around four major axes that are target definition, normal tissue, combined treatments and dose modelling. Under the supervision of the Scientific Council, headed by a coordinator designated by the SFRO and a co-coordinator designated by the SFPM, three leaders coordinate each axis: a radiation-oncologist, a medical physicist and a biologist, who are responsible for organizing a scientific meeting based on the consensus conference methodology to identify priority issues. The selected themes will be the basis for the establishment of a strategic research agenda and a roadmap to help coordinate national basic and translational research efforts in oncological radiotherapy. This work will be published and will be transmitted to the funding institutions and bodies with the aim of opening dedicated calls to finance the necessary human and technical resources. Structuration of a preclinical research network will allow coordinating the efforts of all the actors in the field and thus promoting innovation in radiotherapy.

Fast dose fractionation using ultra-short laser accelerated proton pulses can increase cancer cell mortality, which relies on functional PARP1 protein.

Radiotherapy is a cornerstone of cancer management. The improvement of spatial dose distribution in the tumor volume by minimizing the dose deposited in the healthy tissues have been a major concern during the last decades. Temporal aspects of dose deposition are yet to be investigated. Laser-plasma-based particle accelerators are able to emit pulsed-proton beams at extremely high peak dose rates (~109 Gy/s) during several nanoseconds. The impact of such dose rates on resistant glioblastoma cell lines, SF763 and U87-MG, was compared to conventionally accelerated protons and X-rays. No difference was observed in DNA double-strand breaks generation and cells killing. The variation of the repetition rate of the proton bunches produced an oscillation of the radio-induced cell susceptibility in human colon carcinoma HCT116 cells, which appeared to be related to the presence of the PARP1 protein and an efficient parylation process. Interestingly, when laser-driven proton bunches were applied at 0.5 Hz, survival of the radioresistant HCT116 p53-/- cells equaled that of its radiosensitive counterpart, HCT116 WT, which was also similar to cells treated with the PARP1 inhibitor Olaparib. Altogether, these results suggest that the application modality of ultrashort bunches of particles could provide a great therapeutic potential in radiotherapy.

Slippery but Tough: The Rapid Fracture of Lubricated Frictional Interfaces.

We study the onset of friction for rough contacting blocks whose interface is coated with a thin lubrication layer. High speed measurements of the real contact area and stress fields near the interface reveal that propagating shear cracks mediate lubricated frictional motion. While lubricants reduce interface resistances, surprisingly they significantly increase the energy dissipated Γ during rupture. Moreover, lubricant viscosity affects the onset of friction but has no effect on Γ. Fracture mechanics provide a new way to view the otherwise hidden complex dynamics of the lubrication layer.

The Electrorotation as a Tool to Monitor the Dielectric Properties of Spheroid During the Permeabilization.

This paper proposes to monitor the spheroid's permeabilization within a dedicated microfluidic device using electrorotation analyses. The combination of two electric solicitations, the negative dielectrophoresis force (nDEP) for the spheroid trapping and the electrorotation torque for its dielectric characterization, is used. An estimation of the spheroid dielectric parameters is obtained through the analysis of the rotational velocity curve versus the electric field frequency before and after the PEF application. An observation set-up includes a fast camera that allows time controlled image sequence acquisition. Frames are then digitalized and from the analysis of the rotational velocity of the spheroid, its complex permittivity is determined. Different models, involving the variation of the dielectric properties of the concentric shells that constitute the spheroid, as well as the heterogeneity of cells within each shell, are proposed and used to determine its dielectric properties.

Tuning the ordered states of folded rods by isotropic confinement.

The packing of elastic objects is increasingly studied in the framework of out-of-equilibrium statistical mechanics and thus these appear to be similar to glassy systems. Here, we present a two-dimensional experiment whereby a rod is confined by a parabolic potential. The setup enables spanning a wide range of folded configurations of the rod. Measurements of the distributions of length and curvature in the system reveal the importance of a stacking process whereby many layers of the rod are grouped into branches. The geometrical order of patterns increases with the confinement strength. Measurements of the distributions of energies lead to the definition of an energy scale that is correlated with the elastic energy of the stacked parts of the rod. This scale imposes energy partition in the system and might be relevant to the framework of the thermodynamics of disordered systems. Following these observations, we describe the patterns as excited states of a ground state corresponding to the most ordered geometry. Eventually, we provide evidence that the disordered state of a folded rod becomes spontaneously closer to the ground state as confinement is increased.

Finite-distance singularities in the tearing of thin sheets.

We investigate the interaction between two cracks propagating quasistatically in a thin sheet. Two different experimental geometries allow us to tear sheets by imposing an out-of-plane shear loading. A single tear propagates in a straight line independently of its position in the sheet. In contrast, we find that two tears converge along self-similar paths and annihilate each other. These finite-distance singularities display geometry-dependent similarity exponents, which we retrieve using scaling arguments based on a balance between the stretching and the bending of the sheet close to the tips of the cracks.

Bending waves in crumpled sheets.

Crumpled paper has recently emerged as a model for disordered media. Here we use wave propagation to probe aluminum foils crumpled into balls made by hand or into cylinders obtained by confinement in a container. Surprisingly, the raw dispersion relations appear to differ from sample to sample. They correspond to bending waves that follow an effective path that is shorter than the distance between the input and output points. This can be interpreted in terms of two modes of propagation: slow bending waves and a fast mode whose possible origin is discussed. In addition, the effective paths behave differently in spheres and in cylinders. These results enable the characterization of the sample structure and point toward the geometric rigidity of the configurations.