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Abstract: Intensity modulated radiotherapy (IMRT) is a technique allowing dose escalation and normal tissue sparing for various cancer types. For breast cancer, the main goals when using IMRT were to improve dose homogeneity within the breast and to enhance coverage of complex target volumes. Nonetheless, better heart and lung protections are achievable with IMRT as compared to standard irradiation for difficult cases. Three prospective randomized controlled trials of IMRT versus standard treatment showed that a better breast homogeneity can translate into better overall cosmetic results. Dosimetric and clinical studies seem to indicate a benefit of IMRT for lymph nodes irradiation, bilateral treatment, left breast and chest wall radiotherapy, or accelerated partial breast irradiation. The multiple technical IMRT solutions available tend to indicate a widespread use for breast irradiation. Nevertheless, indications for breast IMRT should be personalized and selected according to the expected benefit for each individual. [Copyright &y& Elsevier]

Abstract: Intensity modulated radiation therapy (IMRT) offers optimal dosimetric and clinical results in terms of acute toxicity, allows augmenting the dose to the target volumes and therefore, appears promising for local control and disease-free survival. However, several pitfalls to this treatment are to be considered, namely a long treatment time and a high number of monitor unit (MU) required. The dosimetric results of the volumetric modulated arctherapy gives at least similar target coverage and preservation of organs at risk, while significantly reducing the number of required MUs and the overall treatment time. This has a potential impact on the treatment quality and the potential risk of secondary cancers. Volumetric modulated arctherapy allows implementation of stereotactic radiation therapy and complex treatments previously considered not feasible with IMRT. The future will involve this technology of high precision to determine the dose and to the target in real time using the image-guided radiotherapy. Tools combining these two methods are in development. [ABSTRACT FROM AUTHOR]

Résumé: Objectif: Comparaison dosimétrique entre différentes techniques de radiothérapie conformationnelle avec modulation d’intensité (RCMI) rotationnelles chez des patients traités pour un cancer pelvien avec irradiation ganglionnaire. Patients et méthodes: Les données dosimétriques de 51 patients inclus prospectivement dans le protocole Artpelvis ont été analysées. Trente-six patients atteints d’un cancer de prostate à haut risque ont été traités, dont 13 par un appareil de tomothérapie hélicoïdale et 23 par RapidArc®. Quinze patients atteints un cancer du canal anal localement évolué ont été traités, dont neuf par un appareil de tomothérapie hélicoïdale et six par RapidArc®. L’analyse a porté sur la comparaison de différents indices de qualité dosimétriques pour les volumes cibles prévisionnels et sur les doses reçues aux organes à risque. Résultats: Malgré de légères différences, l’analyse des paramètres dosimétriques a montré que les deux techniques généraient une bonne et semblable couverture des volumes cibles prévisionnels, conforme à la prescription et aux contraintes prédéfinies. En ce qui concerne les organes à risque, les doses délivrées au bassin et la dose intégrale étaient légèrement plus élevées avec la tomothérapie hélicoïdale. Conclusion: Pour des cancers pelviens traités avec irradiation une ganglionnaire, le RapidArc®et la tomothérapie hélicoïdale permettent d’obtenir des résultats dosimétriques équivalents. L’évaluation du suivi clinique de l’étude Artpelvis permettra de vérifier cette hypothèse d’équivalence. [ABSTRACT FROM AUTHOR]

La chirurgie conservatrice suivie d'une radiothérapie a légitimé le développement de l'association radiochirurgicale conservatrice comme le traitement de référence dans les lésions de petits volumes mais également dans les atteintes plus importantes grâce à la réduction volumique du traitement systémique néoadjuvant. Cependant, certaine toxicité cardiaque, pulmonaire, mais aussi cutanée a altéré l'image et la qualité de vie à long terme d'un nombre limité de femmes traitées se considérant alors comme « surtraitées » ou traitées de manière inappropriée. Pour les tumeurs à bas risque de récidive, plusieurs essais ont exploré l'absence de radiothérapie après traitement conservateur. Le taux de récidive locale était supérieur en cas de chirurgie seule mais sans diminution de la survie globale. Des débats se sont alors multipliés afin de sélectionner le critère de jugement principal le plus pertinent et, à l'exception de rares écoles considérées comme rigoristes, un consensus a été admis sur l'intérêt de diminuer le taux de récidive locale en s'efforçant de développer des techniques peu invasives et en identifiant les patientes à risque de toxicité individuelle. Ainsi, dans le cas d'un risque carcinologique absolu évalué comme faible, les techniques de radiothérapie se sont développées pour permettre un traitement focal, notamment chez les patientes à haut risque de séquelles, permettant un compromis de réduction du taux de récidive locale, mais également d'apparition de séquelles; notamment cutanées. De la même manière, les patientes atteintes de cancer à haut risque de récidive, les volumes à irradier nécessitent des techniques particulières pour mieux couvrir les cibles, en protégeant les organes critiques environnants, notamment cardiaque et pulmonaire. La modulation d'intensité et le complément d'irradiation de la zone locale peuvent nous permettre de mieux contrôler ces maladies de pronostic plus réservé mais à condition également d'intégrer la dimension biologique de risque de toxicité individuelle. Dans cet article, nous développons cette approche de radiothérapie personnalisée en fonction de l'évaluation du risque de récidive locale et d'apparition de toxicité radio-induite. Randomized trials demonstrated similar overall survival between mastectomy and breast-conservative surgery followed by adjuvant radiation therapy. Breast-conservative surgery, with adjuvant radiation therapy, with or without neoadjuvant systemic therapy has become the standard of care for women with early or locally advanced breast cancer. Nevertheless, certain cardiac, lung or cutaneous toxicities may alter the long-term body image and the quality of life of a limited number of patients who consider having had "overtreatment" or treatment outside the best knowledge of science. In case of low-risk breast cancer, several trials have evaluated the carcinologic outcome in absence of radiation therapy after breast-conservative surgery. Local recurrences increased in case of breast-conservative surgery alone but without impact on overall survival. Multiple debates have emerged in order to select the most appropriate evaluation criteria. Finally, a large consensus has considered that reducing local recurrences is important but with modern technologies and after identifying patients of individual radiosensitivity. Indeed, in case of a low absolute risk of local recurrence, radiation therapy techniques have been developed to allow a focal treatment especially for patients with high risk of developing late effects. This kind of compromise takes into account the reduction risk of local recurrences but also the probability of developing radiation-induced cutaneous sequelae. In the same way, for patients considered at high risk of recurrence, the huge volumes need specific techniques to better cover the targets while protecting the surrounding critic organs such as heart and lung. Intensity-modulated radiation therapy and the local high boost may help to decrease local recurrences of these more extended and aggressive diseases while considering the individual radiosensitivity that paves the way of long-term sequelae. In this article, we detail a personalized approach of breast radiation therapy considering the absolute risk of local recurrences and the probability of radiation-induced toxicity appearance. [ABSTRACT FROM AUTHOR]

Purpose Radiation oncologists are responsible for deciding which day-to-day variations are acceptable or not in the treatment setup. However, properly qualified and trained radiation therapists might be capable to perform image registration. We evaluated in our centre the capability and accuracy of radiation therapists to validate positioning images in a prospective study. Methods and patients A total of 84 patients treated for prostate, head and neck, lung or breast cancer was prospectively and randomly included from July 2011 to July 2013 in radiotherapy unit of our institution. For each patient, three positioning images were randomly analysed. Two radiation oncologists analysed all positioning images and shifts decided by the radiation therapists in an independent and blinded way. The radiation oncologists had to decide whether to validate or not this shift and give a corresponding additional shift, if any. A theoretical disagreement rate less than 5% between radiation therapists and radiation oncologists was planned. Results A total of 240 images were analysed (head and neck: 15.0%; prostate: 14.2%; breast: 55.0%; lung: 15.8%). The global disagreement between radiation oncologists and radiation therapists for all the images analysed was 2.5% 95% confidence interval (95% CI) [1.0–5.0], corresponding to six images out of 240. A 100% agreement was reached for prostate and lung images, a 97.2% agreement for head and neck images and a 96.2% agreement for breast images. Conclusions The radiation therapist validation for repositioning images seemed accurate for image-guided radiotherapy in our institution. Periodic evaluation and in-house training are warranted when routine delegation of image registration to radiation therapists is considered. [ABSTRACT FROM AUTHOR]

Abstract: “Dose-painting” radiotherapy allows for a heterogeneous delivery of radiation within the tumour volume by targeting radioresistant areas defined by functional imaging. Within gross tumour volume, it is possible to define one or more target volumes based on biology (biological target volume [BTV]) and to apply a strategy of intensity modulated radiation therapy (IMRT) that will deliver a higher dose to these regions. In this review of the literature, we will highlight the biological elements responsible for radioresistance, and how to image them, then we will detail the radiotherapy techniques necessary for this approach, before presenting clinical results in various situations (head and neck tumours, prostate, brain tumours, etc.). Despite many difficulties that make dose-painting IMRT unusable in routine nowadays, biology-guided radiation therapy represents one of the major pathways of development of radiotherapy in the coming years. [ABSTRACT FROM AUTHOR]

Abstract: Radiation therapy is now widely accepted as an efficacious treatment of localized prostate cancer. Recent advances, namely with the development of conformal radiotherapy, allowed to increase the total dose in the target volumes with greater local control. A forward step achieved with intensity modulated radiotherapy (IMRT) in terms of therapeutic ratio between target volumes and critical organs. IMRT offers an inverse planning dosimetry and a modulation of the fields during irradiation. This article presents recent technical and clinical advances in IMRT focused on prostate cancer. [Copyright &y& Elsevier]

Résumé: Avec l’avènement des nouvelles technologies, la radiothérapie hypofractionnée est de plus en plus proposée (toutes maladies confondues). Nous proposons ici de faire un point sur la place de la radiothérapie hypofractionnée à visée curative dans le cancer du sein, plus particulièrement sur les indications, les doses et volumes. [ABSTRACT FROM AUTHOR]