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The irradiation of non-malignant diseases, essentially for anti-inflammatory purpose, have been largely proposed and performed worldwide until the 1970-80s. At that time, the better assessment of the radio-induced malignancies, essentially in children and young patients, as well as the efficacy of the new anti-inflammatory drugs (steroids and non-steroids), led to the almost disappearance of those techniques, at least in France. In contrast, our German colleagues are still going on treating about 50,000 patients per year for non-malignant (more or less severe) diseases. After a short historical overview, the present article suggests that we were possibly going too far in the rejection of those low-dose irradiations for benign lesions. The recent emergence of new preclinical data, the better understanding of the risk of radio-induced secondary tumours (almost nil in the elderly), and the severity of some situations, such as the cytokine storm of the COVID-19, should probably lead us to reconsider those low - and sometimes very low (less than 1Gy) - irradiations for well-selected indications in the elderly., (Copyright © 2020 Société française de radiothérapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.)

Radiotherapy is 120 years old. A few months only after the discoveries of Roentgen, Becquerel and Marie and Pierre Curie, a few scientists tried to use the newly discovered rays to treat patients. The question of the name of the first "radiation therapist" remains debated. Although often proposed, Emil Grubbé from Chicago seems to have been disqualified. Leopold Freund from Vienna treated a benign cutaneous lesion. Finally, Victor Despeignes from Lyon appears to be the most serious candidate, having treated in 1896 a gastric cancer, and obtaining a very significant tumour regression. The pioneers of radiotherapy paid a heavy tribute to the development of the specialty; a number of them appears on the - most probably incomplete - list of 352 names engraved on the monument dedicated to the "radiation martyrs" in Hamburg. We must keep in mind that it is only within a few years that a handful of brilliant pioneers built the foundations on which radiotherapy could emerge., (Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.)

The article deals with the prevention of cancers only directly related to therapeutic radiation which are distinguished from "secondary cancer". The consideration of the risk of radiation-induced cancers after radiation therapy, although it is fortunately rare events, has become indispensable today. With a review of the literature, are detailed the various involved parameters. The age of the irradiated patient is one of the main parameters. The impact of the dose is also discussed based on the model used, and based on clinical data. Other parameters defining a radiation treatment are discussed one after the other: field with the example of Hodgkin's disease, the type of radiation and the participation of secondary neutrons, spreading and splitting. All these parameters are discussed according to each organ whose sensitivity is different. The article concludes with a list of recommendations to reduce the risk of radio-induced cancers. Even with the advent of conformal radiotherapy, intensity modulation, the modulated volume arctherapy, and the development of specific machinery for the extra-cranial stereotactic, the radiation therapist must consider this risk and use of reasonable and justified control imaging. Although they constitute a small percentage of cancers that occur secondarily after a first malignant tumor, radiation-induced cancers, can not and must not be concealed or ignored and justify regular monitoring over the long term, precisely adapted on the described parameters., (Copyright © 2016. Published by Elsevier SAS.)

Hypofractionation is not a new idea in radiotherapy. The use of a few high-dose fractions has been proposed by some pioneers of our specialty in the early years of the 20th century. Hypofractionation then reappeared several times in the next decades, based on successive radiobiological concepts, a number of them having been shown to be wrong. The nominal single dose (NSD), for example, so fashionable in the 1970's, dramatically underestimated the late toxicity of the high-dose fractions. Consequently, the NSD was directly responsible for a significant increase of the incidence and of the severity of late complications in large cohorts of patients. The linear-quadratic model (LQ) unequivocally improved our understanding of fractionation sensitivity, but one has to keep in mind its limitations, both in the areas of low and high doses per fraction. For more than a decade, prostate cancer has been the subject of fierce discussions about its sensitivity to fractionation. A number of studies have suggested an unusually low (for a malignant tumor) alpha/beta ratio. However, the available data do not allow a precise evaluation of this ratio; "very low" (1.5 Gy), with an advantage of hypofractionation in terms of local control? Or simply "low" (3-4 Gy), only allowing a reduction of the total number of fractions (with a dose adequately reduced)? While waiting for complementary data, it is advised to remain very careful when modifying the classical schemes towards hypofractionation., (Copyright © 2013. Published by Elsevier SAS.)

Since the discovery of X-rays, the goal of radiotherapy has been to deliver an optimal dose in the target volume and the lowest possible dose in the normal tissues. The history of radiotherapy can be divided in three periods. The Kilovoltage era (1900-1939) where only superficial and radiosensitive tumours could be controlled, the Megavoltage era (1950-1995) where Telecobalt and linear accelerators could deliver high doses in all parts of the body. Radiotherapy has since been playing an important curative and conservative role for most cancers. The Computer-Assisted Radiotherapy era (1995-2010) now provides the capacity to optimise the dose distribution in three dimensions. Dose is better conformed to the target volume and organ at risk are better preserved. intensity modulated radio-therapy (IMRT) allows to "shape" concave isodoses and to spare the parotids when irradiating oropharyngeal tumours. Moving targets (lung, liver etc.) are efficiently irradiated using "on-line tracking" and "image-guided radiotherapy". Stereotactic irradiation, first initiated for brain lesions, is now performed for extra-cranial tumours and due to its millimetric precision opens the way back to hypo-fractionated treatments. The next period, already ongoing, is Hadrontherapy with protons and soon helium or carbon ions techniques. In a multidisciplinary strategy, progress in radiotherapy is based on a global approach of the patient and tailored/personalized well targeted treatment of the tumour.

Radiotherapy accidents are exceedingly rare. However, they may have major negative consequences: for health (and sometimes life) of victims as well as for the trust that patients put in radiotherapy and radiation oncologists. Each accident must be pointed out, analysed and reported, in order to allow preventive actions, avoiding repetitive accidents. Through examples of majors accidents occurred all over the world in the last decades, affecting professionals, public or patients themselves, the necessity of transparency is demonstrated. The International Commission of Radiobiological Protection has drawn positive lessons from such accidents and insists on following recommendations: necessity of sufficient number and competent professionals, importance of continuous and initial education, information of professionals and, in general, a strict Quality Assurance program. It is clear that each radiotherapy center remains at risk for errors. It is essential to develop preventive procedures to avoid transformation of errors into accidents. In that context, complete and detailed description and reports of each anomaly or incident must be encouraged as it is done for sectors of aviation or nuclear industry. Radiation oncology must develop such a culture of transparency and of systematic report of all incidents.

Therapeutic exposure to ionising radiation reveals inter-individual variations in normal tissue responses. To examine whether a defect in DNA repair capacity might be involved in such hypersensitive phenotypes, we analysed, using the alkaline comet assay, the response as a function of time to in vitro irradiation at 5 Gy of lymphocytes from 17 breast cancer and 9 Hodgkin's disease patients who developed severe reactions to radiotherapy in comparison with 22 patients with "average" reactions and 24 healthy donors. A difference between breast cancer over-reactors and both patients with normal reactions and healthy donors was observed 30 and 60 min after exposure. A subgroup of breast cancer over-reactors (7/17) reproducibly demonstrated increased levels of residual damage. When the kinetic analyses were prolonged to 120 min, results were in favour of delayed kinetics of rejoining in these patients. Among Hodgkin's disease over-reactors, only one patient showed defective repair. Interestingly, all patients with the most severe complications (grade 4 RTOG/EORTC), i.e., 5 breast cancer and 1 Hodgkin's disease, showed impaired rejoining. Our results suggest that impairment in DNA strand break processing may be associated, in specific subgroups of breast cancer patients, with an individual risk of major toxicity of radiation therapy. Thus, the alkaline comet assay appears to be useful for documenting the DNA repair phenotype in cancer patients., (Copyright 1999 Wiley-Liss, Inc.)

The role of radiotherapy in limited stage Hodgkin's disease (HD) has been gradually changing in the past few decades, resulting in the almost complete disappearance of exclusive irradiation treatment. In reality, exclusive radiotherapy yielded satisfactory results in terms of long-term survival, but in 1999 it was becoming impossible not to take into account the late mortality rates observed in all large cohorts of HD patients. This increased mortality rate has been shown to be related to 1) cardiac toxicity of irradiation, and 2) secondary radiation-induced solid tumors. Thus, the search for efficient but less toxic new strategies can no longer be avoided. For clinically staged, limited HD, precisely defined according to specific prognostic factors, the association of chemotherapy and radiotherapy appears more and more as a standard, and with this therapeutic burden comes parallel efforts for its alleviation. The Previous Radiotherapy experience has shown that, after a chemotherapy-induced complete remission, irradiation of only the initially involved areas was enough. Ongoing trials are now exploring the possibility of a dose de-escalation, from the conventional 36 Gy to 20 Gy (as for children HD), and to maybe 0 Gy (no radiotherapy at all). In parallel, deescalation in the number of chemotherapy cycles is also being investigated. For unfavorable cases, the problem is slightly different, as a higher percentage of cases still appears to be refractory to treatment in this subgroup. Thus, while chemo-radiotherapy has clearly became the standard strategy, efforts are essentially being devoted to identify new--and hopefully more efficient--chemotherapy schemes. In Europe, most of these pending questions will be addressed in the recently initiated trials of the EORTC/GELA and of the GHSG (German Hodgkin Study Group), with the aim of offering to patients treatment which could be at least as efficient as the present schedules, and less toxic in the long term.

The importance of the quality of radiotherapy for Hodgkin's disease has been stressed, particularly in specific American and German studies. A quality control program for verification of technical files for each patient was implemented during the EORTC H8 protocol for patients with a supra-diaphragmatic stage I & II Hodgkin's disease. Today, 161 technical files have been reviewed. While the definition of the target volumes were in accordance with the protocol for most of the patients, we observed 13.6% of major deviations in terms of treated volumes, and 39.7% of major deviations in terms of dose (for volumes, a number of deviations were in the cervical areas, where the upper limit of the field was lowered in view of protecting the parotids, but the others were due to inadequate margins around the mediastinum and the hilum). Some of the dose deviations were due, in some cases, to the addition of a sub-carinal block after 30 Gy, but also, in cervical areas, in misinterpretation of the protocol. In conclusion, such a quality control program is justified by the number of major deviations which have been observed; it seems justified to carry out this program in the future H9 protocol.

The potential tailoring of radiotherapy modalities to the biological characteristics of individual tumours and normal tissues appears to be an exciting way to improve the therapeutic, ratio in radiation therapy patients. Numerous assays have been proposed to provide the clinician with the biological information necessary to predict the outcome after irradiation and to guide the treatment prescription, but none of them has made its way to daily practice. Major difficulties are due to the technical burden of the procedures, the poor characterization of the assayed cells, and, moreover, the high complexity of tumour and normal tissues biology. The present paper reviews the present status of the assessment of tumour cells radiosensitivity, proliferation and oxygenation. Research remains extremely active in the field of biological predictors of response to irradiation. Future steps forwards are expected from progress in the available technologies, (re-)discovery of apoptosis and investigation of normal tissue tolerance.

Scientists now have available a large amount of data dealing with radiation-induced neoplasms. These data went back to anecdotal observations which were made in the very first years of utilization of X-rays and radioactive elements. In fact, it is essentially the strict follow-up of the Japanese populations irradiated by the Hiroshima and Nagasaki bombing which allowed a more precise evaluation of the carcinogenicity of ionizing radiations. Further refinements came from therapeutical irradiations: it is now possible to study large cohorts of patients given well-known doses in well-defined volumes and followed for more than 20 years. Last but not least, a significant increase in the incidence and mortality of thyroid cancer has been detected in children contaminated by iodine radioisotopes after the Tchernobyl accident. Recently, some data suggested the emergence of "clusters" of leukemias close to some nuclear facilities, but this question remains highly polemical, both in France and in the UK. Other questions are still waiting for a precise answer; of course, the extrapolation of our available data to very low doses delivered at very low dose rates, but also the carcinogenic risk at high doses. For these "high" doses (about 30 to 70 Gy), a competition between mutagenesis and cell killing was expected, so that these dose levels were expected to be less carcinogenic than lower (a few sieverts) doses. Actually, recent data suggest that the carcinogenic risk goes on increasing up to relatively important doses. In addition, carcinogenic factors, such as tabacco, anticancer chemotherapy and individual susceptibility, are found more and more to be closely intricated with ionizing radiation in the genesis of a given cancer. Even if a number of questions are still pending, the already available data allow specialists, both in medicine and radioprotection, to edict strict rules which can be reasonably expected to have significantly reduced the risk of radiation-induced neoplasms in most situations.

High doses of ionizing radiation (> 40 Gy) cause severe lung fibrosis in approximately 5% of the cases. There is a twofold increase when chemotherapy is added to ionizing radiation. Lung fibrosis is due to the destruction of lung tissue by ionizing radiation but also to various cytokine effects (PDGF-beta, TGF-beta). Only a minority of patients (approximately 10%) with abnormal X-rays will experience clinical symptoms. The most important radiobiological parameters which accounts for pulmonary tolerance is the fraction size. Irradiation of the heart begets multifarious late sequelae which are often left unrecognized. Chronic pericarditis affects approximately 5% of the patients when the irradiation dose exceeds 40 Gy. Coronary artery disease can be diagnosed in 5 to 10% of the patients. This late complication is more likely to occur if the patient was young at the time of the irradiation or if other risk factors are associated. Valvular defects can be found in 15 to 30% of the patients. However, the mortality rate is very low (0.5%). Finally, conduction defects can also be seen in approximately 5% of the patients. It is very likely that the radiation dose given to the heart should not exceed 30 Gy if late sequelae are to be avoided.

Medical radiation includes radiodiagnosis, nuclear medicine, and radiation therapy. This radiation exposure differs from occupational public exposure, since a direct benefit is conferred upon the patient. The theoretical risks include genetic mutations, carcinogenesis and teratogenesis. In radiodiagnosis and nuclear medicine, the absorbed doses are very low, and no hazardous effect has been observed. In radiation therapy however, where high doses are delivered to a small number of patients, radio-induced carcinogenesis is well documented. It is by no means sure that the nuclear risk must be taken into account, and fully justifies the accomplishments and recommendations of the French radiation protection programs. There is no question that the nuclear risk-benefit equation resulting from medical exposure is tipped heavily in favor of benefit.

Since the discovery of x-rays and radioactivity, the radiotherapeutic management of malignancy has seen numerous spectacular improvements. Beside the widely used photons and electrons, one area of particular interest is the development and refinement of what has become known as "new particles". In this paper we give a brief outline of the properties of such particles and catalogue the impact these have made on the clinical outcome.

From 1972 to 1976 patients at the Gustave Roussy Institute were irradiated for Hodgkin's disease using a modified fractionation schedule (3 fractions of 3.3 Gy per week) for operational reasons. From 1964 to 1971 and from 1977 to 1981, a more conventional regimen (4 fractions of 2.5 Gy per week) was used. The rates of the late complications in these two subsets of patients treated with different fractionation schedules at the same total dose of 40 Gy during the same overall time were compared. Mediastinitis was observed in 19% of the '4 X 2.5 Gy/week' group versus 56% in the '3 X 3.3 Gy/week' group. Pericarditis in 0% versus 9%, gastroduodenal ulceration and severe gastritis in 10 versus 21% and small bowel obstruction in 5 versus 8%. When using the linear quadratic model with an alpha/beta of 2.5 Gy to evaluate the equivalent dose of 40 Gy given in 12 fractions of 3.3 Gy when delivered by fractions of 2.5 Gy, a value of 46.6 Gy is found. This difference of 6.6 Gy in the equivalent doses (for late toxicity) is likely to account for the significant increase of late radiation injuries, such as mediastinitis and pericarditis, in the present study. The local relapse rate was found to be slightly lower in the 3 X 3.3 Gy group. However, this possible benefit cannot offset the considerable increase of late complications.

The association of radiotherapy (RT) and chemotherapy (CT) constitutes one of the main avenues for research in therapeutic oncology. This association has two aims: (1) increase in control rate of primary tumor (this requires either the potentiation of one of the two modalities by the other or the additivity of their effect on tumor cells without a parallel increase in the toxic effects on critical normal tissues); (2) spatial cooperation (RT being used for the control of the primary tumor or of the sanctuaries, and CT for the control of the disseminated disease). In these two strategies, RT and CT should be given up to full doses in order to be effective. The main risk is an increase in the number and severity of the early and late side effects. To circumvent this problem, two possibilities are being explored: (1) use of drugs without serious toxic effects on those critical tissues which are included in the irradiated volume; and (2) avoidance of concomitant administration and introduction of a sufficiently long-time gap between the completion of one modality and initiation of the other. However, in such sequential treatment, a delay of CT until after the completion of RT, or an interruption of CT cycle during the course of RT, allows the occult metastases to increase in size; a similar delay in initiation of RT is also detrimental, as drugs are often not effective on bulky tumors. Moreover, under CT, the cells which are resistant to the cytotoxic drugs may disseminate and initiate chemoresistant metastases. Taking these disadvantages into account, a treatment protocol was proposed in 1980 in which CT and RT are given alternately, without undue delay. Chemotherapy is started with the usual scheduling of one cycle every month. Radiotherapy courses are interdigitated between CT cycles. Each course is initiated 1 week after interrupting CT and continued until 1 week before beginning the subsequent cycle of chemotherapy, and so on until completion of RT. Such split-course RT should have an effect on a tumor comparable to that of a conventional fractionation. This protocol has been used on 24 patients with non-Hodgkin's lymphoma (NHL) of diffuse histology, and 63 patients with small cell carcinoma of the lung. The 2-year relapse-free survivals are promising (in clinical stage II NHL of diffuse histology, 75%; and in small cell lung carcinomas, 33%).(ABSTRACT TRUNCATED AT 400 WORDS)

Heavy particles have been used in transcutaneous radiotherapy for almost 50 years. If these particles and pi mesons remain the domain of highly specialized centers, neutron therapy and, to a lesser degree, proton therapy can be considered common clinical protocols; their limits, complications, efficacities and costs are sufficiently well known to encourage several centers to acquire the necessary equipment. Their practical advantages involve a limited number of patients however, for the patients implicated, the prognoses are appreciably improved by the application of these therapies. Hyperthermia-associated radiotherapy is limited by the poor technical capabilities of the currently available hyperthermia machines. If biological experimentation was highly promising, clinical results to date have been unfulfilling. Nonetheless, hyperthermia-associated interstitial radiotherapy represents an interesting clinical possibility. Radiosensitizers are being extensively developed. The results of randomized therapeutic trials are still contradictory and the toxicity of these products renders their use difficult. New products are being tested; their lower toxicity and potent radiosensitization capacity are encouraging for the future use of this class of compounds.

Résumé L’irradiation hypofractionnée du cancer prostatique s’est développée sur des données radiobiologiques de 1999 en calculant que le rapport alpha/bêta de ce cancer était très bas (1,2 à 1,5 Gy), suggérant que l’hypofractionnement serait susceptible d’améliorer les résultats, avec une meilleure efficacité anti-tumorale et sans augmentation de la toxicité par rapport aux schémas classiques. Dans la foulée, deux types d’hypofractionnement ont été proposés : des schémas d’hypofractionnement « modérés » avec des séances de 2,5 à 4 Gy et des schémas d’hypofractionnement « extrêmes », en techniques stéréotaxiques, avec des séances de 7 à 10 Gy. Pour les hypofractionnements modérés, il paraissait licite d’utiliser le modèle linéaire quadratique pour calculer les équivalences de dose. En revanche, les essais disponibles, s’ils ont souvent montré une « non-infériorité » des schémas hypofractionnés, n’ont pas montré d’avantage évident, même quand les doses équivalentes calculées étaient très supérieures à celles données dans les bras « conventionnels ». Cela pourrait suggérer soit que le rapport alpha/bêta du cancer prostatique n’est pas aussi bas qu’indiqué précédemment, soit que d’autres paramètres radiobiologiques allant dans un sens négatif ont pu annihiler le bénéfice attendu. Pour l’hypofractionnement « extrême », outre les réserves exprimées dans l’utilisation du modèle linéaire quadratique pour les très fortes doses, il persiste de nombreuses inconnues radiobiologiques. La durée totale de l’irradiation, très réduite dans ce cas de figure, peut constituer un élément soit positif (meilleure efficacité anti-tumorale) soit négatif (déficit de réoxygénation). Une durée de séance supérieure à 20–30 minutes peut permettre la réparation de lésions subléthales et réduire l’efficacité. Enfin, l’impact des très fortes doses par fraction sur le microenvironnement ou sur l’immunité est diversement apprécié. Les protocoles actuels d’hypofractionnement extrêmes paraissent montrer des résultats à court-moyen terme encourageants, mais, en l’attente d’essais randomisés, ils doivent intéresser des volumes réduits, avec des techniques stéréotaxiques sans faille et probablement une sélection précise des patients. For prostate cancer, hypofractionation has been based since 1999 on radiobiological data, which calculated a very low alpha/beta ratio (1.2 to 1.5 Gy). This suggested that a better local control could be obtained, without any toxicity increase. Consequently, two types of hypofractionated schemes were proposed: “moderate” hypofractionation, with fractions of 2.5 to 4 Gy, and “extreme” hypofractionation, utilizing stereotactic techniques, with fractions of 7 to 10 Gy. For moderate hypofractionation, the linear-quadratic (LQ) model has been used to calculate the equivalent doses of the new protocols. The available trials have often shown a “non-inferiority”, but no advantage, while the equivalent doses calculated for the hypofractionated arms were sometimes very superior to the doses of the conventional arms. This finding could suggest either an alpha/beta ratio lower than previously calculated, or a negative impact of other radiobiological parameters, which had not been taken into account. For “extreme” hypofractionation, the use of the LQ model is discussed for high dose fractions. Moreover, a number of radiobiological questions are still pending. The reduced overall irradiation time could be either a positive point (better local control) or a negative one (reduced reoxygenation). The prolonged duration of the fractions could lead to a decrease of efficacy (because allowing for reparation of sublethal lesions). Finally, the impact of the large fractions on the microenvironment and/or immunity remains discussed. The reported series appear to show encouraging short to mid-term results, but the results of randomized trials are still awaited. Today, it seems reasonable to only propose those extreme hypofractionated schemes to well-selected patients, treating small volumes with high-level stereotactic techniques. [ABSTRACT FROM AUTHOR]

Abstract: Ionizing radiations induce cell death, causing deterministic or stochastic side-effects. This paper briefly summarizes the biological mechanisms of early and late side-effects of ionizing radiations on healthy tissue. [ABSTRACT FROM AUTHOR]

Abstract: Low-dose brachytherapy for prostate cancer was actually proposed in the first years of the XXth century. Its modern version (iodin 125 or palladium 103 permanent implants) now benefits from some 15 years of experience in a few pioneer centers, with very satisfactory results in term of efficacy/toxicity ratio. More recently, a high-dose rate (HDR) prostate brachytherapy technique has been introduced. Initially utilized essentially as a “boost” irradiation combined with external radiotherapy, it is now being proposed by some authors as a monotherapy for selected localized prostate cancers. Although sophisticated radiobiological models have been proposed to compare those two dose-rates, they are not considered to be valid and reliable enough to compare such different irradiation schemes (A low-dose rate irradiation lasting several months vs a few high-dose fractions given in a few days). When it comes to the implantation techniques, it seems that most of the technical problems which arose for both schemes have been solved, and that the experience of a given team is now much more important than the technique itself. Clinical results cannot be reliably compared so far, the follow-up of the patients treated by HDR brachytherapy being usually shorter, and the patients treated with HDR usually presenting with more advanced lesions. Radioprotection features are very different, with no accident reported for low-dose rate implants. For HDR no irradiation is given at all to the staff and family during a normal application, but one has to face the threat of manipulating high activity sources, with a few accidents or incidents reported in the literature. Financial studies show that for more than 20–30 patients treated in a year, HDR is more economical, although a decrease in the cost of the seeds could change the picture. In conclusion, for low-risk localized prostate cancer, it does not appear reasonable to give up using a low-dose rate technique, which proved to be both efficient and poorly toxic. This actually corresponds to the recent GEC–ESTRO recommendations. For the other patients, a dose escalation is appealing: this could be performed using brachytherapy (LDR or HDR), with or without hormonotherapy. Several trials are ongoing or will be activated very soon to try and answer. [Copyright &y& Elsevier]

Focuses on the treatment strategies of Hodgkin's disease (HD). Description of standards, options and recommendations for the management of HD in 2001; Use of surgery, radiotherapy and chemotherapy for the treatment of HD.

La Société française de radiothérapie oncologique (SFRO) a été créée en 1990. À l'occasion de son trentième congrès annuel, en octobre 2019, une session lui a été consacrée, avec l'objectif d'exposer son fonctionnement, ses actions et ses productions durant ces trois décennies au cours desquelles la radiothérapie et l'oncologie ont été l'objet de transformations sans précédent. Nous nous proposons dans cet article d'exposer le contenu de cette session. The French society of oncological radiotherapy (Société française de radiothérapie oncologique, SFRO) was created in 1990. On the occasion of its thirtieth annual congress, in October 2019, a session was devoted to it, with the objective of exposing its functioning, its actions and its productions during these three decades during which radiotherapy and oncology have undergone unprecedented transformations. We propose in this article to outline the content of this session. [ABSTRACT FROM AUTHOR]

L'augmentation du risque de seconds cancers après radiothérapie prostatique est une préoccupation clinique débattue. L'objectif de l'étude était d'évaluer le risque de survenue de seconds cancers après radiothérapie prostatique dans la littérature, et d'identifier les éventuels facteurs expliquant les discordances de résultat selon les études. Une revue de la littérature a été réalisée, comparant la survenue de seconds cancers chez des patients tous atteints d'un cancer de la prostate, traité ou non par irradiation. Cette revue a inclus 30 études rapportant la survenue de seconds cancers chez 2 112 000 patients pris en charge ou surveillés pour un cancer de la prostate localisé, dont 1 111 000 par radiothérapie externe et 103 000 par curiethérapie. Pour la radiothérapie externe, la moyenne de suivi était de 7,3 années. La majorité des études (80 %) intéressant la radiothérapie externe, comparativement à l'absence de radiothérapie externe, montrait une majoration du risque de seconds cancers avec un hazard ratio variant de 1,13 à 4,9 en fonction de la durée de suivi. Le temps médian de survenue de ces seconds cancers après la radiothérapie variait de 4 à 6 ans. Une augmentation du risque de second cancer de rectum et de vessie a été observée respectivement dans 52 % et 85 % des études. Considérant une période de censure de plus de 10 ans après irradiation, 57 % et 100 % des études retrouvaient une augmentation du risque de cancer rectal et vésical, mais sans aucun impact sur la survie globale. Les études portant sur la curiethérapie n'ont pas mis en évidence d'augmentation du risque de second cancer. Ces études comparatives, le plus souvent anciennes et rétrospectives, avaient de nombreux biais méthodologiques. Dans la limite de nombreux biais méthodologiques, la radiothérapie externe prostatique semble très souvent associée à une augmentation modérée du risque de seconds cancers pelviens, en particulier vésical mais sans impact sur la survie. La curiethérapie n'augmente pas le risque de second cancer. The increased risk of second cancer after prostate radiotherapy is a debated clinical concern. The objective of the study was to assess the risk of occurrence of second cancers after prostate radiation therapy based on the analysis the literature, and to identify potential factors explaining the discrepancies in results between studies. A review of the literature was carried out, comparing the occurrence of second cancers in patients all presenting with prostate cancer, treated or not by radiation. This review included 30 studies reporting the occurrence of second cancers in 2,112,000 patients treated or monitored for localized prostate cancer, including 1,111,000 by external radiation therapy and 103,000 by brachytherapy. Regarding external radiation therapy, the average follow-up was 7.3 years. The majority of studies (80%) involving external radiation therapy, compared to no external radiation therapy, showed an increased risk of second cancers with a hazard ratio ranging from 1.13 to 4.9, depending on the duration of the follow-up. The median time to the occurrence of these second cancers after external radiotherapy ranged from 4 to 6 years. An increased risk of second rectal and bladder cancer was observed in 52% and 85% of the studies, respectively. Considering a censoring period of more than 10 years after irradiation, 57% and 100% of the studies found an increased risk of rectal and bladder cancer, without any impact in overall survival. Studies of brachytherapy did not show an increased risk of second cancer. However, these comparative studies, most often old and retrospective, had many methodological biases. Despite numerous methodological biases, prostate external radiation therapy appears associated with a moderate increase in the risk of second pelvic cancer, in particular bladder cancer, without impacting survival. Brachytherapy does not increase the risk of a second cancer. [ABSTRACT FROM AUTHOR]

Comments on a review on the contribution of apoptosis to tumor radiation response. Conflicting results of clinical studies relating to spontaneous apoptosis levels of treatment outcome in human tumors; Approaches to measuring in vitro radiation-induced apoptosis in patients with non-Hodgkin's lymphoma.

Recently introduced technologies in radiotherapy have significantly improved the clinical outcome for patients. Ion beam radiotherapy, involving proton and carbon ion beams, provides excellent dose distributions in targeted tumours, with reduced doses to the surrounding normal tissues. However, careful treatment planning is required in order to maximise the treatment efficiency and minimise the dose to normal tissues. Radiation exposure from secondary neutrons and photons, particle fragments, and photons from activated materials should also be considered for radiological protection of the patient and medical staff. Appropriate maintenance is needed for the equipment and air in the treatment room, which may be activated by the particle beam and its secondary radiation. This new treatment requires complex procedures and careful adjustment of parameters for each patient. Therefore, education and training for the personnel involved in the procedure are essential for both effective treatment and patient protection. The International Commission on Radiological Protection (ICRP) has provided recommendations for radiological protection in ion beam radiotherapy in Publication 127 Medical staff should be aware of the possible risks resulting from inappropriate use and control of the equipment. They should also consider the necessary procedures for patient protection when new technologies are introduced into clinical practice. [ABSTRACT FROM AUTHOR]