[Radiomics and automation in radiotherapy]. / Radiomique et automatisation en radiothérapie : un duo gagnant !

Cancer incidence is steadily progressing worldwide, in parallel with the aging of the population. Workload is increasing constantly, especially in the fields of oncology and radiotherapy. This is particularly worrysome, as there is a general shortage of skilled professionals in the field (for example in medical physics). Moreover, every single patient does represent an enormous amount of data issued from a wide range of sources. This is especially true as far a medical imaging is concerned. Extraction of morphological data (anatomical location and extent of the tumour) and functional data (tumour biology and metabolism in general) becomes laborious. Moreover, images contain information which cannot be discerned by the human eye. Therefore, to handle shortage of human resources and transform this enormous amount of data automatically, artificial intelligence becomes a «must have¼. We intend to highlight the growing importance of radiomics as a cornerstone in automation of processes in radiotherapy, especially for treatment planification and a more personalized individualized treatment approach.

L'incidence du cancer augmente chaque année suivant de très près l'augmentation de la moyenne d'âge de la population. La charge de travail ne fait qu'augmenter en oncologie, y compris en radiothérapie. Il devient difficile de recruter certains professionnels dans le secteur (comme par exemple, des physiciens). À ce manque, vient s'ajouter l'afflux massif de données pour chaque patient, provenant d'une multitude de sources possibles et, en particulier, la quantité et la complexité des informations contenues dans les différents examens d'imagerie. L'extraction des données structurelles (anatomie et extension de la maladie) et fonctionnelles (biologie et activité métabolique tumorale au sens large) devient laborieuse. De plus,certains éléments contenus dans l'image numérique ne sont tout simplement plus accessibles à nos capacités de perception visuelle. La pénurie annoncée en professionnels experts ainsi que la complexité grandissante de l'analyse de l'image méritent l'apport de l'intelligence artificielle. Nous allons faire le point de l'impact attendu de la «radiomique¼ qui permet l'automatisation des processus, en particulier pour la préparation et l'individualisation des traitements en radiothérapie.

[Palliation by radiation is also our business !] / La radiothérapie palliative, c'est aussi notre rayon !

Radiotherapy (RT), both with a curative and a palliative intent, is one of the cornerstones of oncological treatments. A variety of symptoms linked to cancer can be relieved with RT (such as pain, bleeding, compression exerted by a tumour lesion…). Very often, palliative RT is proposed when other medical treatments (painkillers, morphine…) are no longer efficient, or the patient does not tolerate them anymore. Palliative RT is an integral part of the global supportive oncological care. Indeed, patients' wishes and prognosis are taken into account in each and every step of the treatment pathway. Every treatment deserves an individualized approach and benefits from the best available techniques.

La radiothérapie, à la fois à visée curative et palliative, est l'un des piliers des traitements oncologiques. Une multitude de symptômes liés au cancer (douleurs, saignements, diverses conséquences liées à une compression exercée par une lésion tumorale…) peuvent être soulagés grâce à une radiothérapie palliative (RTP). Bien souvent, la RTP est proposée lorsque les traitements médicamenteux dits «classiques¼ ne font plus suffisamment effet ou si le patient ne les tolère plus (antidouleurs, morphine…). La RTP fait partie intégrante des soins oncologiques de support. En effet, le pronostic du patient, ainsi que ses souhaits, sont pris en compte à chacune des étapes qui constituent le trajet de soins, y compris en RTP. Ainsi, chaque traitement est individualisé et bénéficie des meilleures techniques disponibles.

[Precision medicine in oncology : where do we stand ?] / Médecine de précision en oncologie : où en sommes-nous ?

The «one size fits all¼ approach is seriously challenged by rapid progression of medical knowledge, especially in the field of individual genome expression. It is currently known that the anti-tumour effect of a given treatment and possible side effects at the level of healthy tissues, can at least partly be predicted and explained by individual variations of gene expression. However, most of us realize that these differences in response are also linked to a variety of other individual characteristics, such as for example the environment and socio-economic factors. Without any possible doubt, there are multiple problems (technical, administrative, financial, cultural and ethical) to be solved, before we witness the real irruption of precision medicine and its holistic individualized approach in our daily oncological practice. It has to start with an international effort, disregarding borders of individual countries, in order to obtain very large amounts of data (with a high degree of variability to avoid bias). This holistic approach, at both societal and individual levels, is the entrance door for a personalized approach in care, whether this is curative, predictive or preventive.

Le concept du traitement «taille unique¼ est sérieusement remis en question par la progression accélérée des connaissances du rôle prédictif du génome individuel, tant en matière de la réponse tumorale à un traitement, qu'en ce qui concerne l'apparition d'effets secondaires au niveau des tissus sains. Cette réponse au traitement ne dépend pas simplement de l'expression de quelques gènes, ni d'ailleurs du génome individuel entier. Elle est également influencée par une multitude d'autres facteurs, ce qui requiert une approche holistique prenant en compte, par exemple, l'environnement et les facteurs socio-économiques. Il y a indubitablement des problèmes techniques, administratifs, financiers, culturels et éthiques (protection de la vie privée) à surmonter avant que cette médecine de précision ne soit largement disponible en pratique oncologique journalière. Il faut surtout une collaboration allant largement au-delà des frontières géographiques d'un pays, afin d'assurer une manne suffisante et très variable de données, pour éliminer autant que possible les différents biais. Cette approche holistique, tant au niveau sociétal qu'individuel, ouvre la porte à la personnalisation des soins oncologiques dans le domaine curatif, prédictif et préventif.

[How to improve radiotherapy ? Technological developments and radiotherapy of tomorrow]. / Comment améliorer la radiothérapie ? Évolutions technologiques et radiothérapie de demain.

Radiotherapy established itself in the 20th century as an essential modality in the fight against cancer. The major technological advances of the last decades have allowed a considerable improvement in the therapeutic window. They have also paved the way for stereotactic radiotherapy and new indications. The aim of this article is to enable readers to understand external radiotherapy in 2021 and to understand the challenges of tomorrow. Three areas of improvement in the discipline will be described, the optimization of the prescribed therapeutic dose, the improvement of the distribution of this dose and, finally, the better understanding of radiobiology. For each of these axes, the current implications will be described as well as those which could/should have a major impact on the radiotherapy. FLASH radiotherapy will also be discussed.

La radiothérapie s'est installée au 20ème siècle comme une modalité incontournable dans la lutte contre le cancer. Les avancées technologiques majeures des dernières décennies ont permis une amélioration considérable de la fenêtre thérapeutique. Elles ont également ouvert la voie à la radiothérapie stéréotaxique et à de nouvelles indications. Cet article a pour objectif de permettre aux lecteurs de comprendre la radiothérapie externe en 2021 et d'en appréhender les enjeux de demain. Trois axes d'amélioration de la discipline seront décrits, l'optimisation de la dose thérapeutique prescrite, l'amélioration de la distribution de cette dose et, finalement, la meilleure compréhension de la radiobiologie. Pour chacun de ces axes, des implications actuelles seront données ainsi que celles qui pourraient/ devraient avoir un impact sur la radiothérapie future. La radiothérapie FLASH sera, par exemple, abordée.

[Dental management of head and neck irradiated patients]. / Prise en charge dentaire des patients irradiés en région cervico-faciale.

The oncological management of head and neck tumours is well known and standardized. Radiotherapy is one of the effective tools. However, it induces major changes in healthy tissues: teeth, gums, mucous membranes, salivary glands and bones. Some, like mucositis, are immediate and often reversible; others, like hyposialia or fibrosis, are late effects and often irremediable. These changes greatly affect oral health and make its management more complex. Dental management also becomes a capital element of the care path but, unfortunately, often remains neglected by the patient but also by some practitioners. It concerns all the stages of the clinical course: initial assessment, cancer treatment itself and long-term follow-up. If neglected, the patient's quality of life will be affected and complications, sometimes serious, such as osteoradionecrosis, may occur. Specific care recommendations for maintaining oral health are mentioned, especially for those patients requiring oral cavity irradiation.

La prise en charge carcinologique des tumeurs cervico-faciales est bien connue et codifiée. La radiothérapie fait partie des outils efficaces proposés. Elle entraîne cependant de profondes modifications tissulaires : dents, gencives, muqueuses, glandes salivaires, os. Certaines, comme la mucite, sont immédiates, et souvent réversibles; d'autres, comme l'hyposialie ou la fibrose, s'installent tardivement et souvent définitivement. Ces remaniements altèrent fortement la santé bucco-dentaire et rendent la prise en charge plus complexe. L'approche dentaire devient ainsi un élément capital du trajet de soins. Elle reste, malheureusement, souvent délaissée par le patient lui-même, mais aussi parfois par le praticien. Cette prise en charge concerne toutes les étapes du parcours : bilan initial, traitement carcinologique en soi et suivi à long terme. Si négligée, la qualité de vie du patient sera affectée et des complications, parfois graves, telle l'ostéoradionécrose, peuvent survenir. Sont évoquées ici des recommandations spécifiques de prise en charge bucco-dentaire dans le décours d'une irradiation portant sur la cavité buccale.

[Medical imaging professionals and related specialties : a questioning is essential!] / La médecine du futur. Professionnels de l'imagerie médicale et spécialités annexées : une remise en question s'impose.

Nowadays, we are facing an overwhelming amount of public announcements concerning the rise of artificial intelligence (AI) in the world of medical imaging (including radiology, nuclear medicine and radiotherapy). While most of the applications are still limited to specific niches, there is a general trend to build real transversal platforms. Multiple industrial players, in collaboration with the clinicians in the field, are striving to build those platforms in order to offer plenty of use cases of AI for several purposes and needs (screening/detection, diagnosis and prediction). It is already undeniable that AI far exceeds human capabilities in terms of resolution, speed of image analysis and efficiency. Negative attitudes and skepticism from concerned professionals should be banned. Colla¬boration with data scientists and engineers for the large scale development and implementation should be pushed forward for the benefit of both patients and payers.

S'il y a bien un domaine où les annonces pleuvent en matière de développement de l'intelligence artificielle (IA), c'est le secteur de l'imagerie médicale au sens large du terme (regroupant la radiologie, la médecine nucléaire et la radiothérapie). Les applications, encore souvent uti¬lisées dans des niches précises, ont tendance à devenir beaucoup plus transversales. De multiples acteurs indus¬triels, en partenariat avec les utilisateurs, s'évertuent à construire de réelles plateformes qui offrent aux cliniciens une multitude d'applications utilisables pour combler plusieurs types de demandes et besoins (détection, diagnostic et prédiction). Il est indéniable que la capacité de l'IA dépasse largement nos capacités humaines en matière de résolution de l'image, de rapidité et d'efficience de lecture et d'analyse. Une attitude de négation ou de scepticisme de la part des professionnels du secteur n'est plus de mise. Ils doivent, sans attendre, collaborer avec les spécialistes data et les ingénieurs au développement à large échelle de l'IA en imagerie médicale et ce, au profit des patients et des payeurs.

[Could we consider that radiotherapy is effective outside the irradiation area ? The abscopal effect]. / Peut-on considérer que la radiothérapie agit en dehors du site irradié ? L'effet abscopal.

Radiotherapy is known for its action on local tumoral control. However, it is also able to induce immunomodulatory effects at a systemic level. The abscopal effect (from latin ab scopus which means «away from the target¼) is an illustration of this phenomenon. It is defined as a tumor regression observed outside and at a distance of the irradiation fields. The potential application of this effect of treatment in disseminated cancers is a fast-growing field of research. The optimal therapeutic strategy to achieve this effect remains unknown.

La radiothérapie, connue pour son action sur le contrôle tumoral local, est également capable d'induire des effets immuno-modulateurs systémiques. L'effet abscopal (du latin ab scopus qui signifie «à distance de la cible¼) décrit la régression tumorale observée à distance de la zone d'irradiation. L'exploitation thérapeutique de celui-ci comme traitement des cancers disséminés est un domaine de recherche en plein essor. Actuellement, les modalités thérapeutiques optimales visant à obtenir cet effet demeurent inconnues.

[Multiple vertebral hemangiomas treated simultaneously with CyberKnife® Technology]. / Hémangiomes vertébraux multiples traites simultanément en condition stéréotaxique avec la technologie CyberKnife®.

Haemangioma are benign, vasoformative lesions of endothelial origin. A minority of patients with a vertebral location are symptomatic with neck or back pain. Neurological deficits due to spinal cord compression are rare and mostly observed at the thoracic and upper lumbar spine. Treatment is indicated in case of relevant symptomatology. Several invasive treatment modalities exist such as surgery and intralesional injections, but radiotherapy is the most common treatment for painful lesions. We report a case of a patient with symptomatic bifocal vertebral haemangioma (d9, l3) associated with dorsal and lumbar pain treated simultaneously using a cyberknife® vsi system, with a significant reduction of pain and a limited toxicity.

les hémangiomes sont des malformations vasculaires bénignes, d'origine endothéliale. Une minorité de patients avec des hémangiomes vertébraux sont symptomatiques et présentent des douleurs du cou ou du dos. Le déficit neurologique, occasionné par une compression de la moelle épinière, est rare et touche surtout la colonne thoracique et lombaire supérieure. Un traitement est indiqué si l'hémangiome vertébral est symptomatique. Les techniques invasives comme la chirurgie et les injections intra-lésionnelles peuvent être utilisées, mais la radiothérapie reste le traitement de choix pour les lésions douloureuses. Nous décrivons le cas d'un patient, présentant des douleurs dorso-lombaires, ayant deux hémangiomes localisés en d9 et l3 traités simultanément par le cyberknife® avec un certain succès, notamment du point de vue antalgique, et une toxicité très limitée.

[Comprehensive therapeutic strategy for localized esophageal cancer. Second part : interest of multimodal approaches with or without surgery]. / Comment je traite... les cancers localisés de l'œsophage. Etat actuel des données et stratégie thérapeutique. 2ème partie : l'intérêt des approches multimodales avec ou sans chirurgie.

In recent years, the treatment of esophagus cancer has been completely changed, thus competing the dogma of surgery as the cornerstone treatment. Multimodality treatments as radio-chemotherapy directly followed by surgery, or delayed surgery, significantly improve patient survival compared to surgery alone. Neoadjuvant radiochemotherapy is associated with a higher complete pathologic response rate and improved survival compared to chemotherapy alone. Immediate surgery after radio-chemotherapy is challenged for patients who present a complete clinical response, especially in case of squamous cell carcinoma. Indeed, systematic resection is associated with a significant postoperative mortality rate and has not proven any survival advantage in complete clinical responders as opposed to delayed resection in case of locally persistent or recurrent disease. In squamous cell carcinoma, this could lead to organ preservation, thus avoiding the mortality and durable functional impairment of esophagectomy. This review will discuss the positioning of the multimodality treatment strategy with neoadjuvant radiochemotherapy and chemotherapy and also the strategy of organ preservation.

Depuis quelques années, le traitement du cancer de l'œsophage est en pleine mutation, bousculant ainsi le grand dogme de la chirurgie comme pierre angulaire du traitement. Par rapport à la chirurgie seule, les traitements multimodaux de radiochimiothérapie suivis, directement ou de façon différée, par la chirurgie améliorent significativement les chances de survie prolongée des patients. Comparée à la chimiothérapie néodjuvante, la radiochimiothérapie néoadjuvante démontre un taux de réponse pathologique complet plus élevé qui résulte en une survie prolongée. Chez les très bons répondeurs cliniques, la question de la place de la résection chirurgicale d'emblée est remise en question, surtout pour les carcinomes épidermoïdes. Chez ces patients, la résection systématique par rapport à un acte différé n'offre pas d'avantage en survie, expose le patient à un risque de mortalité significatif alors qu'un certain nombre de patients n'auront jamais à être opérés. Le seul bénéfice actuellement démontré de la résection est une amélioration du contrôle local; or, le devenir du patient est principalement lié à la récidive métastatique. Dans cette revue, nous positionnons et discutons la place des différents traitements multimodaux, chimiothérapie et radiochimiothérapie néoadjuvantes, ainsi que la place de la préservation d'organe par rapport à une chirurgie d'emblée après une radiochimiothérapie.

[Comprehensive therapeutic strategy for localized esophageal cancer]. / Comment je traite... les cancers localisés de l'œsophage. Etat actuel des données et stratégie thérapeutique. 1ère partie : le point sur les approches chirurgicales et non chirurgicales.

Esophageal cancers represent a highly heterogeneous entity mixing two different tumour types : AdenoCarcinoma (ADC) and Squamous Cell Carcinoma (SSC). Developing in the same organ, they are very often considered as a unique pathology and, consequently, the same therapeutic strategy is indiscriminately applied. Esophageal cancer treatments are particularly complex and require a multidisciplinary approach. Despite impressive advances in the tumour statidifaction, surgery, radiotherapy and chemotherapy, the overall prognosis remains grim even at an early stage of the disease. In order to improve the treatment of esophageal cancers and the patient’s survival, we need to consider that ADC and SCC represent two different pathologies requiring specific therapeutic strategies. This review in two parts will present recent data from clinical trials under the scope of tumour histology to set up dedicated therapeutic strategies. In this first part, we explain the restricted role of surgical resection, the prognostic factors and the results of exclusive combined chemotherapy and radiation in localized esophageal cancer.

Les cancers de l'œsophage concernent deux entités d'histologie et de pathogenèse différentes : les carcinomes épidermoïdes (CE) et les adénocarcinomes (ADC). Ils se développent dans un même organe et sont souvent considérés comme une seule et unique maladie avec, comme conséquence, une stratégie thérapeutique identique. Leur traitement est complexe et requiert une prise en charge multidisciplinaire. Bien que les techniques de mise au point de la pathologie, de traitement par chirurgie, de radiothérapie et de chimiothérapie se soient améliorées, le pronostic de la maladie reste péjoratif, même à un stade précoce. L'amélioration de la prise en charge et de la survie des patients nécessite de considérer les CE et les ADC comme deux pathologies distinctes, impliquant des approches thérapeutiques qui leur soient spécifiquement dédiées. Cette revue en deux parties analyse les différents aspects thérapeutiques des cancers de l'œsophage sous l'angle de l'histologie et permet de dégager des stratégies spécifiques. Cette première partie est consacrée aux limites de la résection chirurgicale, aux facteurs pronostiques et aux résultats des traitements par radio-chimiothérapie exclusive des cancers localisés.

[Impact of the use of Luminette® on well-being at work in a radiotherapy department]. / Impact de l'utilisation de la Luminette® sur le bien-être au travail dans un service de radiothérapie.

PURPOSE: Studies showed beneficial effect of light therapy on well-being at work. Our randomized cross-over study aimed at analyzing the effects of light exposition with the use of Luminette® in a hospital department without access to natural light. MATERIALS AND METHODS: The study design proposed an alternation between two periods of four weeks of use of Luminette® and two periods of four weeks without Luminette®. After every period, participants completed questionnaires (sociodemographic data, seasonal and general depression, anxiety, quality of sleep, slumber and general health). RESULTS: Twenty-five persons participated in the study (average age=36.5, SD=7.7). The sample showed several benefits after one month of Luminette®: diurnal slumber (P=0.046), general health perception (P=0.026), physical functioning (P=0.042), pains (P=0.023) and role limitations due to emotional problems (P=0.013). One month later, certain benefits remained without light therapy: diurnal slumber (P=0.028), pains (P=0.044) and emotional problems (P=0.042). CONCLUSION: This study has showed that the use of Luminette® could lead to similar positive results to those obtained with light therapy in other studies. This study has confirmed that Luminette® could have a positive effect on well-being at work.

[Location of radiotherapy centers: an exploratory geographic analysis for Belgium]. / Localisation des centres de radiothérapie : une analyse géographique exploratoire pour la Belgique.

PURPOSE: The distance between the patient's home and a radiotherapy department may represent a hurdle for the patient and influence treatment choice. Therefore, it is necessary to check whether the geographical distribution of radiotherapy centers is in accordance with cancer incidence, taking also into account the cost of travelling to the radiotherapy department. The objective of this study is double; first, to map the current locations of radiotherapy centers across the country and second, to evaluate the observed spatial disparities with appropriate tools. MATERIALS AND METHODS: A model of operational research (P-median) is used to suggest the optimal locations and allocations and to compare them with the current situation. This is an exploratory study with simple inputs. It helps to better understand the current geographical distribution of radiotherapy centers in Belgium as well as its possible limitations. RESULTS-CONCLUSION: It appears that the current situation is on the average acceptable in terms of accessibility to the service and that the method presents huge potentialities for decision making so as to yield a spatial system that is both efficient and equitable.

[Does Radiotherapy have a role in end-of-life care?]. / Y a-t-il une place pour la radiothérapie en fin de vie?

Up to 50% of cancer patients will receive radiation therapy as a part of their treatment. Radiation may be delivered with curative or palliative intent, according to the extent of disease, the patient's performance status and his wishes. The aim of palliative radiotherapy is to locally control primary tumor or metastasis and, thus, to slow down the disease. Another purpose is to decrease symptoms as part of the supportive care in the end of life. The total dose, the dose per fraction and the technique of irradiation used vary with the treatment aim. Indications of radiotherapy in the end of life are reviewed in this paper

[Radiotherapy and urogenital Paget disease]. / Le cas clinique du mois: Radiothérapie dans le cadre d'une maladie de Paget touchant la région génitale.

Urogenital Paget disease is usually treated by surgery. However, in case of recurrence or if multilating surgery is foreseen, radiotherapy seems to open a reasonable alternative. We report a successful treatment with radiotherapy in a patient with urogenital Paget's disease.

[Vascular perfusion as the origin of neoplasm resistance to radio- and chemotherapy]. / La vascularisation tumorale en tant que source de résistance aux traitements de radiothérapie et chimiothérapie.

Angiogenesis is a hallmark of tumours. The newly formed tumour vessels are structurally and functionally abnormal leading to tumour perfusion heterogeneities and subsequently to the development of hypoxic areas. Generally, tumour hypoxia refers to an increasing distance between vasculature and tumour cells (i.e. chronic hypoxia). Chronic hypoxia promotes tumour resistance to treatments and metastasis. The temporal aspect of hypoxia is completely neglected in chronic hypoxia. Intermittent hypoxia (HI) takes the transient and temporal aspect of hypoxia into account. HI is defined as pO2 fluctuations in tumour vessels secondary to transient arrest of tumour blood flow. IH extends the concept of tumour hypoxia to tumour vessels and vascular cells. Transient arrest of tumour blood flow promotes tumour resistance to radio- and chemotherapy treatments and favours metastasis. Moreover, IH protects tumour vessels and endothelial cells against pro-apoptotic stresses and promotes angiogenesis. A comprehensive dissection of the mechanisms leading to IH allows the development and establishment of new therapeutic approaches.

["Triple negative" breast cancer]. / Le cancer du sein "triple négatif".

In western countries, every woman out of eight will develop breast cancer. Over the last two decades, the incidence has considerably increased, but mortality has remained stable and begins to decrease in Europe and the United-States, probably because of new therapy, changes in the use of hormone replacement therapy in postmenopausal women and early diagnosis. Breast cancer is still the first cause of death by cancer in woman under 65. "Triple negative" a breast cancer, a subtype representing 10% of all breast cancers, is characterised by the absence of receptors to oestrogen, progesterone and no histochemical expression of HER-2 growth factor. This subtype carries a poor prognosis and a high incidence of early metastatic recurrence. Furthermore, no target therapy can be defined up to now in this subtype. Thus, identification of new target therapy and prediction of tumoral response to various treatments could help in the global understanding of patients affected by this particularly aggressive type of breast cancer.

[Hypofractionated postoperative radiotherapy for breast cancer]. / Pourquoi les traitements de radiothérapie adjuvante pour cancer du sein ne comptent-ils plus autant de séances?

Postoperative adjuvant radiotherapy for breast cancer is usually applied in twenty five fractions of 2 Gy on the whole breast followed by a boost dose on the initial tumour site. Facing a continuous rise of the workload in radiotherapy departments, investigators have tried to reduce the burden of such a treatment approach both for the patients and the departments as available resources are not unlimited. These hypo-fractionated treatment schedules have been tested and validated in randomized controlled trials. Based on this evidence a new treatment algorithm has been built up as it has been shown that those schedules do provide similar levels of local control with comparable or an even lower risk of toxicity.

[Image guided stereotactic treatment with CyberKnife yields surgical precision]. / Vers une radiothérapie chirurgicale: nécessité d'une radiothérapie guidée par l'imagerie.

The field of radiation oncology is rapidly evolving especially thanks to the tremendous progress in robotics and computer sciences. One of the consequences is the implementation of a technique like the CyberKnife. This particular radiation therapy modality allows the use of "ablative" radiation doses, a concept which is not even conceivable with conventional approaches. This has been made possible by major changes in the ways target and margins around are defined and the way radiation therapy is fractionated. The result of these changes is for some tumours a doubling of the radiobiological effect of the ionizing irradiation. In order to cover the target with the highest possible conformality, without harming surrounding healthy tissues, optimized definition of the target is key. It is not only important to get information on the extent of the target with the highest possible resolution, but it is also important to assess the content, i.e., metabolic heterogeneity. The developments made in the field of diagnostic and functional radiology and nuclear medicine do allow to take advantage of the numerical information to individualize and adapt treatment prescription, even consider modification throughout the course of irradiation.

[Head and neck tumors: standards of care and new approaches]. / Les tumeurs de la sphère ORL: standards de traitement et nouvelles approches en radiothérapie.

We intend to review the general value of radiotherapy in the management of head and neck cancer. Our aim is to define a treatment protocol which is evidence-based and therefore of use in daily clinical practice. There is general agreement on the efficacy of the concomitant schedules combining radiotherapy and chemotherapy, both in the adjuvant setting as well as in the exclusive non-surgical approach. This however does not preclude further research aiming at optimizing the therapeutic index. As far as neoadjuvant chemotherapy is concerned, applied prior to radical local treatment, there are no conclusive data available which allows us to implement this treatment option in routine clinical practice. This approach deserves further investigations and patients should be entered in well designed prospective randomized trials.

[Ductal carcinoma in situ (DCIS): can radiotherapy be avoided?]. / Carcinome intracanalaire (in situ) du sein: pouvons-nous raisonnablement éviter la radiothérapie pour certaines patientes opérées?

There is a never ending discussion on the need for radiotherapy after conservative breast surgery for DCIS (Ductal Carcinoma In Situ). It is true that adjuvant irradiation does not yield any difference in overall survival in the published randomized trials. However, postoperative irradiation after breast conserving surgery (BCS) has been shown to significantly reduce ipsilateral breast event (IBE), whether this is a DCIS recurrence or a recurrence with an invasive component. The real question is to define if there is a subgroup of patients for whom radiotherapy can be withheld without taking any significant local risk. Nowadays, we are not able to define such a subgroup as the possible selection criteria to avoid radiotherapy have never been validated within a well designed prospective randomized trial. Therefore, we think that there is no available evidence to avoid radiotherapy after BCS for DCIS. However, radiotherapy is not indicated after mastectomy.