[en] The astronauts have to spend more time in space and the colonization of the moon and Mars are in the cross hairs of international agencies. The cosmic radiation from which we are protected on ground by atmosphere and by the terrestrial magnetosphere (.4 mSv/year according to Who) become really threatening since 20 km altitude, delivering an average radiation dose of a therapeutic kind to astronauts with peaks related to solar events. It is composed in majority of hadrons: protons (85%) and heavy ions (13%), but also photons (2%) of high energy (GeV/n)). the incurred risks are multiple: early ones(cataract, central nervous system damages, whole body irradiation) but especially delayed ones (carcinogenesis). The astronauts radiation protection turns poor and the rate of death risk by cancer returning from a mission on Mars has been estimated at 5%. The Nasa created in 2004 a summer school aiming to awareness young researchers to the space radiobiology specificities. Areas concerned as follow: radioinduced DNA damage and repair, cell cycle, apoptosis, bystander effect, genome instability, neuro degeneration, delayed effects and carcinogenesis in relation with radiation exposure. (N.C.)

[en] Beyond the understanding of biological bases, the chemotherapy-radiotherapy associations must continue to be tested by broad clinical tests: the therapy benefit being understandable in terms of anti tumor efficiency but also in term of tolerance in healthy tissues. (N.C.)

[en] Improvements in accuracy stand as the heart of the success of today's radiotherapy. The dose may be delivered with a sub millimetric accuracy, may also conform to complex shapes, or track external and internal organ motions. In parallel, we may increase the tumour's radio-curability by modulating the biological effects generated by ionizing radiation into the patient. It was precisely the topic of the 2009 Lucien-Mallet prize organized by the French Society for Radiation Oncology (SFRO) and the Centre Antoine-Beclere under the auspices of the Fondation de France. In this review we will precisely describe the integrated molecular response to ionizing radiations. Starting from early observations, we are going to introduce the concept of cellular radiosensitivity as the global response of the irradiated cell. We will then focus into the cell and especially its nucleus. We will describe here the most complex and deleterious radioinduced damages. In the next chapter, we will dissect the molecular pathway that aims to detect and repair the previous lesions. The last part of the review will finally deal with the diagnostic, prognostic and therapeutic impacts emerging from the alliance between clinical and molecular radiobiology. (author)

[en] A space flight is submitted to 3 main sources of radiation: -) cosmic radiation (4 protons/cm²/s and 10000 times less for the heaviest particles), -) solar radiation (10⁸ protons/cm²/s in the solar wind), -) the Van Allen belt around the earth: the magnetosphere traps particles and at an altitude of 500 km the proton flux can reach 100 protons/cm²/s. If we take into account all the spatial missions performed since 1960, we get an average dose of 400 μGray per day with an average dose rate of 0.28 μGray/mn. A significant risk of radiation-induced cancer is expected for missions whose duration is over 250 days.The cataract appears to be the most likely non-cancerous health hazard due to the exposition to comic radiation. Its risk appears to have been under-estimated, particularly for doses over 8 mGray. Some studies on astronauts have shown for some a very strong predisposition for radio-induced cancers: during the reparation phase of DNA breaking due to irradiation, multiple new damages are added by the cells themselves that behave abnormally. (A.C.)

[en] Individual response to ionizing radiation is an important information required to apply an efficient radiotherapy treatment against tumour and to avoid any adverse effects in normal tissues. In 1981, Fertil and Malaise have demonstrated that the post-irradiation local tumor control determined in vivo is correlated with clonogenic cell survival assessed in vitro. Furthermore, these authors have reminded the relevance of the concept of intrinsic radiosensitivity that is specific to each individual organ (Fertil and Malaise, 1981) [1]. To date, since clonogenicity assays are too time-consuming and do not provide any other molecular information, a plethora of research groups have attempted to determine the molecular bases of intrinsic radiosensitivity in order to propose reliable and faster predictive assays. To this aim, several approaches have been developed. Notably, the recent revolution in genomic and proteomics technologies is providing a considerable number of data but their link with radiosensitivity still remains to be elucidated. On another hand, the systematic screening of some candidate genes potentially involved in the radiation response is highlighting the complexity of the molecular and cellular mechanisms of DNA damage sensing and signalling and shows that an abnormal radiation response is not necessarily due to the impairment of one single protein. Finally, more modest approaches consisting in focusing some specific functions of DNA repair seem to provide more reliable clues to predict over-acute reactions caused by radiotherapy. In this review, we endeavored to analyse the contributions of these major approaches to predict human radiosensitivity. (authors)

[en] The authors report the study of dose escalation for the treatment of spinal in two types of Ewing tumours. They used 5 dose levels at the rate of five 1,6 Gy per week. They compare different radiotherapy techniques: three-dimensional conformation radiotherapy, static intensity-modulated conformational radiotherapy, helical tomo-therapy, volume-modulated arc-therapy (VMAT), stereotactic radiotherapy, and proton-therapy (in passive diffusion). It appears that it is possible to safely and efficiently deliver until 70,4 Gy in some Ewing tumours. In child, exclusive radiotherapy might become a local treatment option and would require a clinic trial and comparison with exclusive surgery or post-operative radiotherapy. Short communication

[en] Carbon ion therapy is an innovative radiotherapy modality for non-operable radio-resistant or resected cancers. Its efficiency is due to improved ballistic accuracy and biological efficiency. The authors present the first phase III study of carbon ion therapy in France. This technique concerns some sarcomas and adenoid cystic carcinomas of head and neck. The authors indicate the possible treatment procedures (doses, sessions) for the different types of cancers, and how the study is to be performed (number of patients, randomization, and multicentre approach). Short communication

[en] As 200.000 patients including 700 children are treated by irradiation every year in France, and as more than 5 per cent are exposed to non-predictable after-effects, the authors report the development of a diagnosis test for adults based on the in-vitro estimation of the functional repair and signalling of DNA double strand breaks. By using indirect immunofluorescence, they demonstrate a quantitative correlation between cellular quantitative sensitivity and the rates of non-repaired DNA double strand beaks. This approach, called Preditox, has been validated on 80 patients and presents the required characteristics to be a screening test of radio-sensitive patients. Short communication

[en] At the beginning of the 21. century, radiation biology is at a major turning point in its history. It must meet the expectations of the radiation oncologists, radiologists and the general public, but its purpose remains the same: to understand the molecular, cellular and tissue levels of lethal and carcinogenic effects of ionizing radiation in order to better protect healthy tissues and to develop treatments more effective against tumours. Four major aspects of radiobiology that marked this decade will be discussed: technological developments, the importance of signalling and repair of radiation-induced deoxyribonucleic acid (DNA) damage, the impact of individual factor in the response to radiation and the contribution of radiobiology to better choose innovative therapies such as proton-therapy or stereotactic body radiation therapy (SBRT). A translational radiobiology should emerge with the help of radiotherapists and radiation physicists and by facilitating access to the new radio and/or chemotherapy modalities. (authors)

[en] Patients with locally advanced grade 2-3 extremity/truncal soft tissue sarcomas (STS) are at high risk of recurrence. The objective of this study was to assess the efficacy and feasibility of neoadjuvant concurrent chemoradiotherapy (cCRT) in selected grade 2-3 patients with limb or trunk wall STS, and to compare this schedule to a sequential approach combining neoadjuvant chemotherapy and adjuvant radiotherapy. We retrospectively included patients who underwent neoadjuvant cCRT at two comprehensive cancer centers from 1992-2016. We then compared these results to those of patients treated with preoperative chemotherapy and postoperative radiotherapy from a third comprehensive cancer center with a propensity score matched analysis. A total of 53 patients were treated by neoadjuvant cCRT; 58 patients could be matched with 29 patients in each treatment group after propensity score matching. Disease-free survival and overall survival at 5 years were 54.9 and 63.5%, respectively with neoadjuvant cCRT, with no significant difference when compared to the sequential treatment group. R0 resection rate was higher (90.9 vs 44.8%, p < 0.01) in the cCRT group than in the sequential treatment group during a shorter therapeutic sequence (118 vs 210.5 days, p < 0.01), with no impact on the surgical procedure or postoperative complications. cCRT is feasible with acceptable immediate and late toxicities. It could facilitate surgery by increasing the R0 resection rate and improve patient compliance by shortening the therapeutic sequence.