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Abstract: These last years, the new irradiation techniques as the conformal 3D radiotherapy and the IMRT are strongly correlated with the technological developments in radiotherapy. The rigorous definition of the target volume and the organs at risk required by these irradiation techniques, imposed the development of various image guided patient positioning and target tracking techniques. The availability of these imaging systems inside the treatment room has lead to the exploration of performing real-time adaptive radiation therapy. In this paper we present the different image guided radiotherapy (IGRT) techniques and the adaptive radiotherapy (ART) approaches. IGRT developments are focused in the following areas: 1) biological imaging for better definition of tumor volume; 2) 4D imaging for modeling the intra-fraction organ motion; 3) on-board imaging system or imaging devices registered to the treatment machines for inter-fraction patient localization; and 4) treatment planning and delivery schemes incorporating the information derived from the new imaging techniques. As this paper is included in the “Cancer–Radiotherapie” special volume dedicated to the lung cancers, in the description of the different IGRT techniques we try to present the lung tumors applications when this is possible. [Copyright &y& Elsevier]

Résumé Les principales indications de curiethérapie des cancers de la tête et du cou localisées sont les tumeurs des lèvres et la pyramide nasale, de la cavité buccale et de l’oropharynx. Les tumeurs du cavum sont aujourd’hui plus accessibles à la radiothérapie conformationnelle avec modulation d’intensité. La curiethérapie peut être réalisée seule ou après une radiothérapie externe ou une chirurgie. Elle fait partie des traitements de recours pour les secondes localisations en territoire irradié et les situations périopératoires à risque. La curiethérapie de débit pulsé permet de reproduire les connaissances acquises de bas débit de dose et l’optimisation de la distribution de la dose. Les résultats de séries de patients traités avec le haut débit font leur apparition dans plusieurs localisations. Cet article fait état des données issues des recommandations du Groupe européen de curiethérapie–European Society for Radiotherapy and Oncology (Gec-ESTRO) publiées en 2017, tenant compte des connaissances issues des séries en bas débit de dose, et actualisées pour les techniques de débit pulsé et de haut débit de dose. The main indications of the brachytherapy of head and neck cancers are the limited tumours of the lip, the nose, the oral cavity and the oropharynx. Nasopharynx tumours are nowadays treated by intensity-modulated radiotherapy. This technique can be exclusive, associated with external radiotherapy or postoperative. It can also be a salvage treatment for the second primaries in previously irradiated areas. If the low dose rate brachytherapy rules remain the reference, the pulse dose rate technique allows the prescription of the dose rate and the optimisation of the dose distribution. Results of high dose rate brachytherapy are now published. This paper reports the recommendations of the Gec-ESTRO, published in 2017, and takes into account the data of the historical low dose rate series, and is upgraded with the pulsed-dose rate and high dose rate series. [ABSTRACT FROM AUTHOR]

Résumé Objectifs de l’étude L’esthésioneuroblastome ou neuroblastome olfactif représente une entité rare. Nous rapportons dans cet article notre expérience et une synthèse des principales données de la littérature. Patients et méthodes Nous avons analysé rétrospectivement les données cliniques et thérapeutiques des patients pris en charge au centre hospitalier Lyon Sud pour des esthésioneuroblastomes olfactifs histologiquement confirmés. Résultats Les dossiers de dix patients pris en charge entre 1993 et 2015 ont été analysés. Le stade initial, selon la classification de Kadish, était C dans 90 % des cas. Le suivi médian était de 136 mois. La probabilité de survie globale à 10 ans était de 90 %. Celle de survie sans progression était de 70 % et 50 % respectivement à 5 et 10 ans. Neuf patients (90 %) ont bénéficié d’une résection chirurgicale de première intention. Sept des neuf patients opérés (77 %) ont reçu une radiothérapie adjuvante conformationnelle tridimensionnelle, un une radiothérapie avec modulation d’intensité statique, un une arcthérapie volumétrique modulée ( n = 1). La dose moyenne délivrée au site tumoral était de 61 Gy. Aucun patient n’a reçu d’irradiation ganglionnaire prophylactique. Deux patients ont bénéficié d’une chimiothérapie concomitante. Cinq tumeurs (50 %) ont récidivé, une localement, deux dans les ganglions et deux dans le cerveau. Conclusion Ces données semblent comparables à celles de la littérature. En l’absence d’étude prospective, et devant le faible nombre de cas rapportés dans la littérature, il est important de poursuivre l’étude de ces tumeurs et de publier l’expérience de chaque centre afin d’améliorer leur prise en charge. Purpose Olfactory neuroblastoma or esthesioneuroblastoma is a rare entity among head and neck neoplasms. In this paper, we report the experience of our institution and compare it with a comprehensive review of the literature. Patients and methods We retrospectively analysed clinical and treatment data of patients referred to the Lyon Sud University Hospital (France) for histologically proven olfactive esthesioneuroblastoma. Results Ten patients treated between 1993 and 2015 have been analysed. Disease stage at diagnosis, according to the Kadish staging system, was C in 90% of cases. Median follow-up was 136 months. Ten-year overall survival was 90%. Five- and ten-year progression-free survival were 70% and 50%. Nine patients (90%) underwent surgical resection first. Seven of the nine patients who underwent resection (77%) received adjuvant three-dimensional (3D)-conformal radiotherapy ( n = 7), intensity-modulated radiotherapy ( n = 1), or volumetric arctherapy ( n = 1). The mean dose to the tumour volume was 61 Gy. None of the patients received elective nodal irradiation. Two patients received concurrent chemotherapy. Five patients (50%) presented with disease recurrence, which was local ( n = 1), nodal ( n = 2) and cerebral ( n = 2). Conclusion Our results are consistent with the literature. Because of the lack of prospective study and the low number of cases in the literature, each institution's experience is of the utmost important to improve standardised management of these tumours. [ABSTRACT FROM AUTHOR]

Résumé Depuis une vingtaine d’années, le développement de nanoparticules comprenant des éléments de haut numéro atomique comme agents radiosensibilisants est en plein essor. Le design de ces nano-objets doit respecter les contraintes « classiques » liées au développement de nanoparticules pour une application en oncologie, tout en permettant d’augmenter l’effet de la dose locale dans la zone tumorale en épargnant les tissus sains environnants. Dans ce cadre, l’injection intraveineuse de tel nanomédicament devient possible. Les différents points à prendre en considération pour la mise au point d’une nanoparticule administrable par voie systémique et possédant une activité radiosensibilisante seront discutés à partir de l’exemple de la nanoparticule AGuIX. Cette nanoparticule de quelques nanomètres de diamètre hydrodynamique, composée de polysiloxane et de chélates de gadolinium, a démontré son intérêt lors de nombreuses études précliniques et est en cours d’évaluation pour un essai clinique de phase I chez l’homme. En plus d’augmenter l’efficacité de la radiothérapie, elle peut être utilisée comme agent de contraste pour l’IRM et constitue donc un nanomédicament théranostique pour la médecine personnalisée. Since twenty years, many nanoparticles based on high atomic number elements have been developed as radiosensitizers. The design of these nanoparticles is limited by the classical rules associated with the development of nanoparticles for oncology and by the specific ones associated to radiosensitizers, which aim to increase the effect of the dose in the tumor area and to spare the health tissues. For this application, systemic administration of nanodrugs is possible. This paper will discuss the development of AGuIX nanoparticles and will emphasize on this example the critical points for the development of a nanodrug for this application. AGuIX nanoparticles display hydrodynamic diameters of a few nanometers and are composed of polysiloxane and gadolinium chelates. This particle has been used in many preclinical studies and is evaluated for a further phase I clinical trial. Finally, in addition to its high radiosensitizing potential, AGuIX display MRI functionality and can be used as theranostic nanodrug for personalized medicine. [ABSTRACT FROM AUTHOR]

Résumé Certaines tumeurs rares et de l’enfant sont de bonnes indications de protonthérapie, qui permet une forte probabilité de contrôle tumoral sans toxicité sévère ; la multiplication des centres de traitement s’est accompagnée d’une accumulation de données dosimétriques et cliniques pour d’autres cancers. L’objectif de cette étude est de faire une mise au point sur les indications potentielles de protonthérapie. Une recherche a été faite sur Medline avec les mots clés suivants : proton beam radiotherapy , cancer , heavy particle , charged particle . Aucun essai de phase III comparant la protonthérapie avec la meilleure photonthérapie n’a pour l’instant été publié, mais de nombreuses études rétrospectives ont montré des avantages dosimétriques et cliniques potentiels importants, laissant présager d’un avantage en termes de toxicité pour la protonthérapie, en particulier lorsque la contrainte de dose implique des organes en parallèle (tumeurs thoraciques et abdominales) ; de nombreux essais de phase 0, I, II, III et IV sont en cours pour déterminer la place de la protonthérapie dans les cancers les plus fréquents. L’utilisation de cette technique dans les cancers les plus fréquents est en expansion dans le cadre d’essais, mais certaines indications pourraient être envisagées devant des avantages dosimétriques majeurs in silico avec la protonthérapie. Proton beam therapy is indicated as a treatment for some rare tumours and paediatric tumours because the technique allows a good local control with minimal toxicity; the growing number of centres that use proton beam therapy is associated with an increase of dosimetric and clinical data for other malignant tumours as well. This paper reviews potential indications of proton beam therapy. A systematic review on Medline was performed with the following keywords proton beam therapy, cancer, heavy particle, charged particle. No phase III trial has been published using proton beam therapy in comparison with the best photon therapy, but numerous retrospective and dosimetric studies have revealed an advantage of proton beam therapy compared to photons, above all in tumours next to parallel organs at risk (thoracic and abdominal tumours). This could be accompanied with a better safety profile and/or a better tumoural control; numerous phase 0, I, II, III and IV studies are ongoing to examine these hypotheses in more common cancers. Use of proton beam therapy is growing for common cancers within clinical trials but some indications could be applied sooner since in silico analysis showed major advantages with this technique. [ABSTRACT FROM AUTHOR]

Abstract: Although the same simple laws govern cancer outcome (cell division repeated again and again), each tumour has a different outcome before as well as after irradiation therapy. The linear-quadratic radiosensitivity model allows an assessment of tumor sensitivity to radiotherapy. This model presents some limitations in clinical practice because it does not take into account the interactions between tumour cells and non-tumoral bystander cells (such as endothelial cells, fibroblasts, immune cells…) that modulate radiosensitivity and tumor growth dynamics. These interactions can lead to non-linear and complex tumor growth which appears to be random but that is not since there is not so many tumors spontaneously regressing. In this paper we propose to develop a deterministic approach for tumour growth dynamics using chaos theory. Various characteristics of cancer dynamics and tumor radiosensitivity can be explained using mathematical models of competing cell species. [Copyright &y& Elsevier]

Abstract: PET imaging is now considered a gold standard tool in clinical oncology, especially for diagnosis purposes. More recent applications such as therapy follow-up or tumor targeting in radiotherapy require a fast, accurate and robust metabolically active tumor volumes delineation on emission images, which cannot be obtained through manual contouring. This clinical need has sprung a large number of methodological developments regarding automatic methods to define tumor volumes on PET images. This paper reviews most of the methodologies that have been recently proposed and discusses their framework and methodological and/or clinical validation. Perspectives regarding the future work to be done are also suggested. [Copyright &y& Elsevier]

Abstract: Purpose: A way to improve the accuracy of lung radiotherapy for a patient is to get a better understanding of its lung motion. Indeed, thanks to this knowledge it becomes possible to follow the displacements of the clinical target volume (CTV) induced by the lung breathing. This paper presents a feasibility study of an original method to simulate the positions of points in patient''s lung at all breathing phases. Patients and methods: This method, based on an artificial neural network, allowed learning the lung motion on real cases and then to simulate it for new patients for which only the beginning and the end breathing data are known. The neural network learning set is made up of more than 600 points. These points, shared out on three patients and gathered on a specific lung area, were plotted by a MD. Results: The first results are promising: an average accuracy of 1mm is obtained for a spatial resolution of 1×1×2.5mm3. Conclusion: We have demonstrated that it is possible to simulate lung motion with accuracy using an artificial neural network. As future work we plan to improve the accuracy of our method with the addition of new patient data and a coverage of the whole lungs. [Copyright &y& Elsevier]

Abstract: Xerostomia is one of the most a common complication of radiotherapy for head and neck cancers, affecting quality of life. Parotid glands produce approximately 60% of saliva and submandibular glands 20% of saliva while the rest is secreted by sublingual and accessory salivary glands. Methods of measuring the salivary output are collection of unstimulated or stimulated saliva or 99mTc-pertechnate scintigraphy. Several studies demonstrated that late salivary dysfunction after radiotherapy has been correlated to the mean parotid gland dose, with recovery occurring with time. Severe xerostomia could be avoided if at one parotid gland is spared to a mean dose of less than approximately 25–30Gy. Clinical benefit of submandibular gland sparing is more controversial. A mean dose less than 39Gy could preserve submandibular gland function. This paper aims to review main studies evaluating tolerance dose of salivary glands. [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: Head and neck squamous cell carcinomas are frequently diagnosed at an advanced stage. Their treatment remains controversial, and has to be multidisciplinary. External beam radiotherapy is a recognized treatment option after radical curative surgery in order to improve local control. Different adjuvant treatment options have been studied in order to improve the outcome of these patients. We review in this paper the different prognostic factors indicating an adjuvant treatment and the interest of treatment intensification in bad prognostic patients. [Copyright &y& Elsevier]

Abstract: The planning of radiotherapy has known major developments during the last years. With the emergence of news techniques such as conformational radiotherapy, intensity modulated radiation therapy or stereotactic radiation therapy, the definition of target volumes was of great importance. The recommendations for the target volumes definition have been defined in the ICRU 50 and 62 reports, without any guidelines for volume delineation. Among the incertainties that may influence the outcome after irradiation, the intra- and interobservers variations in delineation are the most important. Many teams have offered guidelines or atlases to homogenize these volumes and reduce these variations related to medical intervention. The aim of this paper is to present the main recommendations. [Copyright &y& Elsevier]

Abstract: The MEAH, a French national agency working on health services organization, has led a two-year campaign on safety improvement in radiotherapy centers. The pilot project involved three voluntary French cancer centers in 2005 and 2006. Building on the results of this project, a roll-out campaign has been launched, involving more than 50 additional cancer centers from 2007 and on. This paper presents the results of experiences of these campaigns. Notably, the axes of improvement chosen by professionals, such as risk analysis or use of checklists are discussed. [Copyright &y& Elsevier]

Abstract: Purpose: This paper presents the development of a protocol for quality control of a megavoltage cone beam CT imaging system (MVCB) mounted on a Siemens Oncor 6MV linear accelerator. Materials and methods: Several parameters were controlled on the MVCB system: (1) the initial geometric calibration of the system; (2) the quality of the images (geometric distortion, uniformity, spatial resolution, low contrast resolution) for various protocols; (3) the correspondence between the intensity of voxels and electronic densities; (4) the dose delivered when achieving a MVCB. These tests were done mainly with two cylindrical phantoms specific to the quality control (QC) of a MVCB system, supplied by Siemens, and with the Catphan 600 phantom (The Phantom Laboratory) and Quasar™ Multipurpose Body phantom (Modus Medical Devices Inc). Results: The results of the quality control of the images were within the tolerances. The use of the Catphan 600 phantom was inadequate for the QC of MVCB images. These tests also highlighted the need to correct the MVCB images for the “cupping artefact” for dose calculation purpose. Conclusion: The initial characteristics of the MVCB imaging system were established. Such testing also provided the assessment of the influence of various parameters on the image quality as well as the associated dose delivered during their acquisition, and emphasized the corrections needed to use MVCB images for dose calculation. [Copyright &y& Elsevier]

Abstract: Post-operative concomitant chemoradiotherapy is now a standard of care for locally advanced gastric carcinomas. Definition of target volumes is based on natural history of the disease and on analysis of the sites of local relapses. This paper summarized the general principles of target delineation, in a conformal approach. [Copyright &y& Elsevier]

Abstract: Large modifications are on going in our medical practice in oncology (cancer incidence, ageing, rules, authorizations, billings…). To obtain the best results as possible implies a quality control of the equipments (drugs, machines…), of the professionals (certification) and of the organisations (accreditations). Radiation oncology plays a key role in the multidisciplinary treatment of cancer ant is very sensitive to quality assurances due to its specificities: different tumours, various patients, multiple sequences of treatment with high tech machines and information systems. From 2003, a progress policy has been developed with the MeaH (Mission d''évaluation et d''audit hospitalier). Rapidly, the transfer of security policies from industry to medicine has been considered. This paper will present the first results and their potential implications in the field of oncology. [Copyright &y& Elsevier]

Abstract: Adjuvant Radiotherapy has been shown to significantly reduce locoregional recurrence but this advantage is associated with increased cardiovascular and pulmonary morbidities. All uncertainties inherent to conformal radiation therapy must be identified in order to increase the precision of treatment; misestimation of these uncertainties increases the potential risk of geometrical misses with, as a consequence, underdosage of the tumor and/or overdosage of healthy tissues. Geometric uncertainties due to respiratory movements or set-up errors are well known. Two strategies have been proposed to limit their effect: quantification of these uncertainties, which are then taken into account in the final calculation of safety margins and/or reduction of respiratory and set-up uncertainties by an efficient immobilization or gating systems. Measured on portal films with two tangential fields, CLD (central lung distance), defined as the distance between the deep field edge and the interior chest wall at the central axis, seems to be the best predictor of set-up uncertainties. Using CLD, estimated mean set-up errors from the literature are 3.8 and 3.2 mm for the systematic and random errors respectively. These depend partly on the type of immobilization device and could be reduced by the use of portal imaging systems. Furthermore, breast is mobile during respiration with motion amplitude as high as 0.8 to 10 mm in the anteroposterior direction. Respiratory gating techniques, currently on evaluation, have the potential to reduce effect of these movements. Each radiotherapy department should perform its own assessments and determine the geometric uncertainties with respect of the equipment used and its particular treatment practices. This paper is a review of the main geometric uncertainties in breast treatment, due to respiration and set-up, and solutions proposed to limit their impact. [Copyright &y& Elsevier]

Abstract: Hypofractionation (i.e. the use of fewer higher fractional doses than usual) is not a new concept. It had actually been proposed in the early year of Radiotherapy by the German and Austrian specialists. In the seventy''s, supported by the –– wrong –– hypotheses which gave birth to the NSD (Nominal Standard Dose), hypofractionation reappears. The consequential increase of late complications which was observed led the radiation oncologists to give up again using large doses per fraction, except for a few specific situations, such as palliative treatments. We are recently facing a new “come-back” of hypofractionation, in particular for breast and prostate cancers. In the case of breast cancer, the aim is clearly to look for more “convenience” for both the patients and the physicians, proposing shorter irradiation schedules including a lesser number of fractions. Some “modestly” hypofractionated schemes have been proposed and used, without apparently altering the efficacy/toxicity ratio, but these results have been seriously questioned. As for prostate cancer, the situation is different, since in that case new radiobiological data are at the origin of the newly proposed hypofractionation schedules. A number of papers actually strongly suggested that the fractionation sensitivity of prostate cancer could be higher than the one of the tissues responsible for late toxicity (i.e the exact opposite of the classical dogma). Based on those data, several hypofractionated schemes have been proposed, with a few preliminary results looking similar to the ones obtained by the classical schedules. However, no randomised study is available so far, and a few recent radiobiological data are now questioning the new dogma of the high fractionation sensitivity of prostate cancer. For those two –– frequent –– cancers, it seems therefore that prudence should prevail before altering classical irradiation schedules which have proven their efficacy, while staying open to new concepts and proposing well-designed randomised trials in specific cases. [Copyright &y& Elsevier]

Abstract: The objective of this paper is to give some practical landmarks for the delineation of target volumes and organs at risk in Intensity Modulated Radiation Therapy for Nasopharyngeal Carcinoma. This delineation, drawn from anatomo-clinical data, natural history of the disease and radiological pre-treatment evaluation, seems to be easier to define than the delineation of other head and neck cancer localisations (oropharynx and oral cavity for example). Experience inside national and international cooperative groups should tend to standardize this initial and fundamental step of Nasopharyngeal Conformal Radiotherapy. [Copyright &y& Elsevier]

Abstract: Local-regional radiation therapy is one of the major therapeutic means in the management of breast cancer. Three questions however arise from the important advances achieved in this domain in the past years. The first question concerns the possibilities to identify and overcome the radioresistance of a subset of tumours. The second question is how to recognize women likely to benefit from adjuvant radiation therapy, and therefore to diminish treatment indications in other groups. Finally, the third question is how to identify subjects at high risk for long term injury following breast irradiation, in order to adapt techniques and indications in such populations. The major advances of breast cancer molecular genetics in the past years should provide clinicians with tools to answer these important questions. In this paper, we review the molecular germline (BRCA1, BRCA2, ATM, …) and somatic (p53, tyrosine kinase receptors, as well as actors of cell cycle, signal transduction, apoptosis, DNA repair …) main bases of breast cancer radiosensitivity. Recent methods of exploration of the genetic background of both the host and the tumours (gene and protein expression profiles) are also reviewed as major tools of breast cancer management in the next few years. [Copyright &y& Elsevier]

The paper presents the characteristics, the place and the limits of brachytherapy in prostate radiotherapy. While sparing the rectal wall, erectile function as well as urinary continence, I125 and Pd103 permanent implants represent interesting approaches for good prognosis tumours in comparison to surgery or conformal external beam radiotherapy with similar cure rates. Overcoming easily the problems of organ motion and patient positioning while allowing doses per fraction as high as 10 Gy, brachytherapy is an excellent boosting method in the treatment of intermediate or unfavourable prognosis tumours of which α/β is 1,5 Gy. Encouraging biological control rates of 80–90% have been published in phase II trials. Compared to external beam radiotherapy, the heterogeneity of irradiation inside the clinical target volume should increase the probability of cure as for a specific dose, a significant part will be overdosed. So far, 120–130% of the prescribed doses are delivered to the peripheral zone at the origin of 70% of tumours. On the opposite, this heterogeneity is inducing an overdosage of the urethral bed at the price of higher toxicity levels in situations of previous obstructive syndrome and urethral stenosis. A better integration of the therapeutic modalities available, brachytherapy included, should increase our curative possibilities in the radiation treatment of prostatic cancer. [Copyright &y& Elsevier]

Prognosis of pancreatic carcinoma remains poor, with one-year and five-year overall survival rates of 20 and 5% respectively. Only 5 to 15% of patients present with tumors amenable to resection. Long-term (5 years) survival after curative resection is less than 20%, and the median survival is about 12 months. This paper updates recent trends about concomitant chemoradiation. At first, a review of the studies on adjuvant chemoradiation after surgery is proposed. Then, indications of preoperative chemoradiation for patients with localized resectable adenocarcinoma are discussed. The last part concerns the most important and recent studies about chemoradiation in locally advanced pancreatic cancer, either with 5-fluoro-uracile or based on new drugs like gemcitabine. [Copyright &y& Elsevier]

This paper reports the patient care experience during the trajectory of the radiotherapy. Plights are multiple. Patients are confronted with a complex and unknown distressing space, an irrelevant information, a banalisation of side effects, an isolation with a frequent inadequate support of their family or the caregivers team, with the fear of a definitive abandonment at the end of the treatment without conforting follow-up. It is imperative to state a real policy in order to improve the patient support. Sensibilisation and training of the caregivers, in spite of a frequent overbooking technical work, is required in a pluridisciplinary approach to provide a relevant reception with the collaboration of psychologists, social workers and self care groups and associations. The personal implication of the physicians and technologists is also essential. The simple smile is the intangible proof of the reliable emotional support. [Copyright &y& Elsevier]

The conformal radiotherapy approach, three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT), is based on modern imaging modalities, efficient 3D treatment planning systems, sophisticated immobilization systems and rigorous quality assurance and treatment verification. The central objective of conformal radiotherapy is to ensure a high dose distribution tailored to the limits of the target volume while reducing exposure of normal tissues. These techniques would then allow further tumor dose escalation. Head-and-neck tumors are some of the most attractive localizations to test conformal radiotherapy. They combine ballistic difficulties due to particularly complex shapes (nasopharynx, ethmoid) and problems due to the number and low tolerance of neighbouring organs like parotids, eyes, brainstem and spinal cord. The therapeutic irradiation of head-and-neck tumors thus remains a challenge for the radiation oncologist. Conformal radiotherapy does have a significant potential for improving local control and reducing toxicity when compared to standard radiotherapy. However, in the absence of prospective randomized trials, it is somewhat difficult at present to evaluate the real benefits drawn from 3DCRT and IMRT. The published clinical reports on the use of conformal radiotherapy are essentially dealing with dosimetric comparisons on relatively small numbers of patients. Recently, a few publications have emphasized the clinical experience of several precursor teams with a suitable follow-up. This paper describes the current state-of-the-art of 3DCRT and IMRT in order to evaluate the impact of these techniques on head-and-neck cancers irradiation. [Copyright &y& Elsevier]

The conformal radiotherapy approach, three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT), is based on modern imaging modalities, efficient 3D treatment planning systems, sophisticated immobilization devices and demanding quality assurance and treatment verification. The main goal of conformal radiotherapy is to ensure a high dose distribution tailored to the limits of the target volume while reducing exposure of healthy tissues. These techniques would then allow a further dose escalation increasing local control and survival. Non-small cell lung cancer (NSCLC) is one of the most difficult malignant tumors to be treated. It combines geometrical difficulties due to respiratory motion, and number of low tolerance neighboring organs, and dosimetric difficulties because of the presence of huge inhomogeneities. This localization is an attractive and ambitious example for the evaluation of new techniques. However, the published clinical reports in the last years described very heterogeneous techniques and, in the absence of prospective randomized trials, it is somewhat difficult at present to evaluate the real benefits drawn from those conformal radiotherapy techniques. After reviewing the rationale for 3DCRT for NSCLC, this paper will describe the main studies of 3DCRT, in order to evaluate its impact on lung cancer treatment. Then, the current state-of-the-art of IMRT and the last technical and therapeutic innovations in NSCLC will be discussed. [Copyright &y& Elsevier]

Since January 2001, radiotherapy treatments with modulated intensity beams (IMRT) have started at the Centre Oscar-Lambret. This paper presents the tests and measurements made before the clinical implementation as well the quality control performed before each routine treatment. We use the treatment planning system Helax-TMS (MDS-Nordion) and the Primus accelerator (Siemens) linked to the Lantis network with Primeview© and Simtec© modules (Siemens) allowing to deliver intensity modulated beams with Step-and-Shoot technique. A prostate case and a head and neck case have been studied and have permitted to evaluate the benefit of IMRT compared to a “classical” conformal radiotherapy. In a second time, we have tested the accelerator''s capabilities to deliver these intensity modulated beams, id-est. the accuracy of the leaf positions and the linearity of the monitor chamber. The third step has been the verification of the dose distributions calculated by Helax-TMS, id-est, the dose for different segment sizes, the dose profiles for an intensity modulated beam and the dose distribution for all the traitment beams. The used phantom has been especially developed at the Centre Oscar-Lambret for IMRT. The results have allowed to start clinical treatments and to establish a quality control set for this technique. The next step is the real time dosimetry with a portal imager. [Copyright &y& Elsevier]

Résumé La radiothérapie garde une place majeure dans la prise en charge des métastases osseuses. Elle est principalement utilisée dans un but palliatif à visée antalgique ou décompressive. De façon plus récente, les développements de la radiothérapie stéréotaxique et de la radiothérapie conformationnelle avec modulation d’intensité laissent entrevoir son utilisation à dose curative dans la maladie oligométastatique. L’objectif de cet article est de rapporter les indications et les modalités de la radiothérapie dans ces différentes situations. Radiotherapy plays a major role in palliative treatment of bone metastases. Recent developments of stereotactic radiotherapy and intensity modulated radiation therapy give the possibility to treat oligometastatic diseases. The objective of this paper is to report indications and treatment modalities of radiotherapy in these situations. [ABSTRACT FROM AUTHOR]

Résumé À partir d’une revue de la littérature, cet article définit les limites de délinéation pour les organes critiques, puis les contraintes de dose sur ces derniers lorsque la radiothérapie est délivrée selon un étalement et fractionnement classiques ou en hypofractionnement, tel qu’utilisé dans la radiothérapie en conditions stéréotaxiques. From a review of literature, the objective of this paper is to define limits for delineation of organs at risk and dose constraints in this latter when radiotherapy is delivered with conventional fractionation or with hypofractionation as for stereotactic body radiation therapy. [ABSTRACT FROM AUTHOR]

Abstract: Constant progress in medical imaging and particularly magnetic resonance imaging has profound impact in planning for stereotactic radiosurgery and radiotherapy. The purpose of this paper is to discuss the integration of medical imaging modalities in the planning process. Principles of generic algorithms to calculate stereotactic coordinates are treated for tomographic imaging and digital substraction angiography, and their accuracies are analyzed in a review of the literature. The algorithmic foundations and performance of automatic intermodality co-registration methods are developed. Finally, the MRI sequences useful in planning and follow-up are discussed and the role of MR angiographic sequences compared to conventional X-ray angiography in the particular case of the arteriovenous malformation planning. [Copyright &y& Elsevier]