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Prostate cancer is the most common cancer of men over 50 years old. Localized prostatic cancer treatment may be responsible of a decline of patient's quality of life. The main actors of treatment are now focused on minimizing functional consequences of treatments. The radiation oncologist has a central role in patient monitoring. The follow-up is codified by official recommendations of learned societies to enhance the post-cancer period. The main objective of this article is to review the recommendations for clinical and biological follow-up. An inventory of the functional consequences of the various treatments will be detailed, and particularly those caused by androgen deprivation therapy, with a review of precautions before implementation, adverse effects and their management, as well as monitoring recommendations. The analysis of quality of life after curative treatment and suggestions to improve monitoring will also be discussed.

National audience; Intensity modulated radiotherapy combined with image guided radiotherapy has led to increase the precision of external beam radiotherapy. However, intra or inter-fraction anatomical variations are frequent during the treatment course and can cause under-dosing of the target volume and/or over-dosing of the organs at risk. Several adaptive radiotherapy (ART) strategies can be defined to compensate these anatomical variations. The purpose of this article is to provide an overview of available ART strategies: offline, online, hybrid (library of treatment plans) or in real-time, while considering the arrival of MR-Linac devices in radiotherapy departments. The tools required to these ART strategies such as auto-segmentation, deformable image registration, calculation of the daily dose or dose accumulation, are also described. Implementing an ART strategy requires a rigorous quality assurance process, at each stage and on the entire workflow, as well as prior organization and training from of all the trades. A strong multidisciplinary involvement is finally required in order to ensure ART treatments.

Intensity modulated radiotherapy combined with image guided radiotherapy has led to increase the precision of external beam radiotherapy. However, intra or inter-fraction anatomical variations are frequent during the treatment course and can cause under-dosing of the target volume and/or over-dosing of the organs at risk. Several adaptive radiotherapy (ART) strategies can be defined to compensate these anatomical variations. The purpose of this article is to provide an overview of available ART strategies: offline, online, hybrid (library of treatment plans) or in real-time, while considering the arrival of MR-Linac devices in radiotherapy departments. The tools required to these ART strategies such as auto-segmentation, deformable image registration, calculation of the daily dose or dose accumulation, are also described. Implementing an ART strategy requires a rigorous quality assurance process, at each stage and on the entire workflow, as well as prior organization and training from of all the trades. A strong multidisciplinary involvement is finally required in order to ensure ART treatments.

Prostate cancer is the most common cancer of men over 50 years old. Localized prostatic cancer treatment may be responsible of a decline of patient's quality of life. The main actors of treatment are now focused on minimizing functional consequences of treatments. The radiation oncologist has a central role in patient monitoring. The follow-up is codified by official recommendations of learned societies to enhance the post-cancer period. The main objective of this article is to review the recommendations for clinical and biological follow-up. An inventory of the functional consequences of the various treatments will be detailed, and particularly those caused by androgen deprivation therapy, with a review of precautions before implementation, adverse effects and their management, as well as monitoring recommendations. The analysis of quality of life after curative treatment and suggestions to improve monitoring will also be discussed.

Resume Objectif de l’etude L’objectif de ce travail etait d’ecrire le controle local, la survie globale, la survie sans progression et la toxicite de la radiotherapie en conditions stereotaxiques par CyberKnife® pour les carcinomes hepatocellulaires. Materiels et methodes Il s’agit d’une etude observationnelle retrospective et multicentrique, menee au centre Eugene-Marquis a Rennes et au centre hospitalier universitaire Bretonneau a Tours, entre novembre 2010 et decembre 2016. Le traitement a ete realise en situation de sauvetage, en d’attente d’une transplantation hepatique ou en dernier recours. Resultats Cent trente-six patients ont ete consecutivement inclus dans l’etude. Le suivi median etait de 13 mois. La dose mediane totale prescrite etait de 45 Gy en trois fractions sur 5 jours. Les taux de survie globale, de survie sans progression et de controle local a 1 an et 2 ans etaient respectivement de 79,8 % et 63,5 % ; de 61,3 % et 39,4 % ; de 94,5 % et 91 %. Deux evenements de toxicite aigue de grade 3 et deux de toxicite tardive de grade 4 ont ete rapportes. Sept patients ont souffert d’une hepatite radio-induite classique et 13 d’une hepatite radio-induite non classique. Le stade selon les criteres diagnostiques de Barcelone (Barcelona Clinic Liver Cancer [BCLC]), l’indice de performance selon l’Organisation mondiale de la sante et le volume cible previsionnel etaient correles avec la survie globale en analyse de Cox unifactorielle. Conclusion La radiotherapie en conditions stereotaxiques est un traitement efficace et bien tolere pour les carcinomes hepatocellulaires inoperables ou en attente de transplantation. La toxicite est principalement liee au terrain cirrhotique et implique une selection des patients et des contraintes de doses strictes sur les organes a risque.

International audience; Simulating the response to radiotherapy (RT) in cancer patients may help devising new therapeutic strategies. Computational models make it possible to cope with the multi-scale biological mechanisms characterising this group of diseases. We present in this paper an in silico model of tumour growth and radiation response, capable of simulating a whole RT protocol of prostate cancer. Oxygen diffusion, proliferation of tumour cells, angiogenesis based on the VEGF diffusion, oxygen-dependent response to irradiation and resorption of dead cells were implemented in a multi-scale framework. A sensitivity analysis using the Morris screening method was performed on 21 computational tissues, initialised from prostate histopathological specimens presenting different tumour and vascular densities. The dose per fraction and the duration of the cycle of tumour cells were identified as the most important parameters of the model.

Prostate cancer is a sensitive adenocarcinoma, in more than 80% of cases, to chemical castration, due to its hormone dependence. Locally advanced and/or high-risk cancer is defined based on clinical stage, initial prostate specific antigen serum concentration value or high Gleason score. Hormone therapy associated with radiation therapy is the standard of management and improves local control, reduces the risk of distant metastasis and improves specific and overall survival. Duration of hormone therapy, dose level of radiation therapy alone or associated with brachytherapy are controversial data in the literature. The therapeutic choice, multidisciplinary, depends on the age and comorbidity of the patient, the prognostic criteria of the pathology and the urinary function of the patient. Current research focuses on optimizing local and distant control of these aggressive forms and incorporates neoadjuvant or adjuvant chemotherapy and also new hormone therapies.

For locally advanced cervical cancer (LACC), anatomy correspondence with and without BT applicator needs to be quantified to merge the delivered doses of external beam radiation therapy (EBRT) and brachytherapy (BT). This study proposed and evaluated different deformable image registration (DIR) methods for this application. Twenty patients who underwent EBRT and BT for LACC were retrospectively analyzed. Each patient had a pre-BT CT at EBRT boost (without applicator) and a CT and MRI at BT (with applicator). The evaluated DIR methods were the diffeomorphic Demons, commercial intensity and hybrid methods, and three different biomechanical models. The biomechanical models considered different boundary conditions (BCs). The impact of the BT devices insertion on the anatomy was quantified. DIR method performances were quantified using geometric criteria between the original and deformed contours. The BT dose was deformed toward the pre-CT BT by each DIR method. The impact of boundary conditions to drive the biomechanical model was evaluated based on the deformation vector field and dose differences. The GEC-ESTRO guideline dose indices were reported. Large organ displacements, deformations, and volume variations were observed between the pre-BT and BT anatomies. Rigid registration and intensity-based DIR resulted in poor geometric accuracy with mean Dice similarity coefficient (DSC) inferior to 0.57, 0.63, 0.42, 0.32, and 0.43 for the rectum, bladder, vagina, cervix and uterus, respectively. Biomechanical models provided a mean DSC of 0.96 for all the organs. By considering the cervix-uterus as one single structure, biomechanical models provided a mean DSC of 0.88 and 0.94 for the cervix and uterus, respectively. The deformed doses were represented for each DIR method. Caution should be used when performing DIR for this application as standard techniques may have unacceptable results. The biomechanical model with the cervix-uterus as one structure provided the most realistic deformations to propagate the BT dose toward the EBRT boost anatomy.

International audience; Purpose - The aims of this multicentre retrospective study of locally advanced head and neck cancer (LAHNC) treated with definitive radiotherapy were to (1) identify positron emission tomography (PET)-F-fluorodeoxyglucose (F-FDG) parameters correlated with overall survival (OS) in a training cohort, (2) compute a prognostic model, and (3) externally validate this model in an independent cohort. Materials and methods - A total of 237 consecutive LAHNC patients divided into training (n = 127) and validation cohorts (n = 110) were retrospectively analysed. The following PET parameters were analysed: SUV, metabolic tumour volume (MTV), total lesion glycolysis (TLG), and SUV for the primary tumour and lymph nodes using a relative SUV threshold or an absolute SUV threshold. Cox analyses were performed on OS in the training cohort. The c-index was used to identify the highly prognostic parameters. A prognostic model was subsequently identified, and a nomogram was generated. The model was externally tested in the validation cohort. Results - In univariate analysis, the significant PET parameters for the primary tumour included MTV (relative thresholds from 6 to 83% and absolute thresholds from 1.5 to 6.5) and TLG (relative thresholds from 1 to 82% and absolute thresholds from 0.5 to 4.5). For the lymph nodes, the significant parameters included MTV and TLG regardless of the threshold value. In multivariate analysis, tumour site, p16 status, MTV35% of the primary tumour, and MTV44% of the lymph nodes were independent predictors of OS. Based on these four parameters, a prognostic model was identified with a c-index of 0.72. The corresponding nomogram was generated. This prognostic model was externally validated, achieving a c-index of 0.66. Conclusions - A prognostic model of OS based on primary tumour and lymph node MTV, tumour site, and p16 status was proposed and validated. The corresponding nomogram may be used to tailor individualized treatment.

The delegation of the on board imaging position control, from the radiation oncologist to the therapist, is justified by the generalization of the image-guided radiotherapy techniques which are particularly time consuming. This delegation is however partial. Indeed, the validation of the position by the therapist can be clearly performed when the registration is based on bony landmark or fiducial. The radiation oncologist needs however to make the validation in case of large target displacement, in more complex soft tissue-based registration, and in case of stereotactic body radiation therapy. Moreover, this delegation implies at least three conditions which are first the training of the staff, then the formalization of the procedures, responsibilities and delegations and finally, the evaluation of the practices of IGRT.

Resume La connaissance des mouvements et deformations intrapelviens entre et pendant les fractions des differents volumes cibles (prostate, vesicules seminales, loge de prostatectomie et aires ganglionnaires) ainsi que celle des principaux organes a risque (vessie et rectum) permettent de definir des marges entre les volumes cibles anatomoclinique et previsionnel rationnelles en fonction des differentes techniques d’irradiation et de leurs incertitudes. En cas de radiotherapie guidee par l’image, les marges prostatiques et des vesicules seminales peuvent se situer entre 5 et 10 mm. Les marges autour de la loge de prostatectomie varient de 10 a 15 mm et celles autour du volume cible anatomoclinique ganglionnaire entre 7 et 10 mm, selon les directions de l’espace. Les techniques de radiotherapie stereotaxique permettent une reduction des marges, qui sont de 3 a 5 mm autour de la prostate.

The prostate external beam radiotherapy techniques are described, when irradiating the prostate or after prostatectomy, with and without pelvic lymph nodes. The following parts are presented: indications of radiotherapy, total dose and fractionation, planning CT image acquisition, volume of interest delineation (target volumes and organs at risk) and margins, Intensity modulated radiotherapy planning and corresponding dose-volume constraints, and finally Image guided radiotherapy.

Resume La radiotherapie guidee par l’image est decrite dans ses differents equipements et leurs mises en œuvre. Elle peut etre basee soit sur des rayonnements ionisants generant une imagerie bidimensionnelle de haute (MV) ou basse (kV) energie ou une imagerie tridimensionnelle (tomographie conique [CBCT] ou scanographie de haute energie [MV-CT]), soit sur des rayonnements non ionisants (echographie, imagerie optique, radiofrequence ou IRM). La radiotherapie adaptative est ensuite presentee dans ses principes de realisation. L’utilisation par les manipulateurs en electroradiologie medicale (MERM) des images de controle au poste de traitement est ensuite precisee, ainsi que la dose eventuellement delivree par l’imagerie embarquee et enfin le controle qualite des dispositifs de guidage par l’image.

Resume Objectif de l’etude En cas de radiotherapie prostatique avec modulation d’intensite (RCMI), precedee d’une chirurgie premiere par curage ganglionnaire pelvien et exerese des vesicules seminales, l’objectif de l’etude etait d’evaluer le benefice dosimetrique d’une reduction du volume cible. Patients et methodes Vingt-cinq patients atteints d’un cancer de prostate de haut risque ont eu une chirurgie premiere suivie d’une RCMI prostatique et d’une hormonotherapie. Quatre plans de traitement ont ete simules pour chaque patient, a partir des scanographies realisees avant et apres la chirurgie et correspondant aux volumes cibles suivants : prostate–vesicules seminales–aires ganglionnaires pelviennes, prostate–aires ganglionnaires pelviennes, prostate–vesicules seminales, et prostate seule. La dose totale delivree aux aires ganglionnaires pelviennes et aux vesicules seminales etait de 46 Gy, et celle a la prostate de 80 Gy. Resultats L’addition des vesicules seminales puis des aires ganglionnaires pelviennes multipliait respectivement par 1,6 et 6,5 le volume cible previsionnel. La reduction progressive du volume cible previsionnel « prostate–vesicules seminales–ganglions pelviens » a « prostate–vesicules seminales » puis a « prostate seule » conduisait a une diminution de la dose moyenne dans la paroi rectale de 49 Gy a 42 Gy puis a 36 Gy, et du risque predit de rectorragies tardives de 4,4 % a 3,2 % puis a 2,4 % ( p p Conclusion Une chirurgie premiere avec curage et exerese des vesicules seminales avant la RCMI conduit probablement a une diminution moderee de la toxicite digestive.

Introduction Cardiac stereotactic body radiation therapy (SBRT) appears to be effective for patients with refractory ventricular tachycardia (VT) by delivering a single ablative radiation dose of 25 Gy to the arrhythmogenic region. Definition of treatment volume is a critical step, integrating combination of cardiac and respiratory motion. The main objective of this study was to evaluate the impact of cardiac and respiratory motion on the definition of target volume. Methods and materials The study presents the targeting data from the first patient enrolled in our institution for SBRT. Treatment planning was performed using different imaging modalities: a respiration-correlated 4D CT, a cardiac-correlated 4D CT, a MRI scan and electrophysiological data from prior catheter ablation. A registration was performed between the different imaging modalities. Respiratory and cardiac motions were quantified in left–right (LR), anteroposterior (AP) and supero-inferior (SI) directions for the target (calcifications) and for the defibrillation lead. The treatment area was delineated using diastolic and systolic cardiac phases of the cardiac-correlated 4D CT, to optimally define a treatment zone accounting for target's displacements related to cardiac motions. Results Target motions amplitude induced by heartbeats were close to those induced by respiration. Respiratory motions of the target were not correlated to that of defibrillation lead (see Table 1 ). The target volume was 15.9 cm3 and 17.7 cm3 for the diastolic and systolic phases, respectively, and 20.7 cm3 when joined together. These differences emphasise the target deformation, and the need of 4D cardiac imaging data for SBRT. Conclusion We showed that optimal definition of the target volume in SBRT requires respiratory and cardiac correlated images. The use of defibrillation lead as a surrogate might result in target localisation inaccuracies, which need to be taken into account in the final planning target volume.

Introduction et but de l’etude La radiotherapie ablative pour la tachycardie ventriculaire refractaire est une application emergente de radiotherapie stereotaxique qui consiste a delivrer une dose ablative de 25 Gy en une seance unique au niveau d’une region cardiaque arythmogene. Elle implique la definition d’un volume cible previsionnel complexe integrant la combinaison des battements cardiaques et des mouvements respiratoires. L’objectif de cette etude etait d’evaluer l’impact geometrique des mouvements cardiaques et respiratoires sur la definition du volume cible. Materiel et methodes L’etude a ete realisee sur le premier patient pris en charge dans notre institution pour une tachycardie ventriculaire refractaire du septum interventriculaire basal. La planification a ete basee sur : une tomodensitometrie synchronisee a l’electrocardiogramme avec injection de produit de contraste (TDM-4Dcardiaque), une tomodensitometrie synchronisee a la respiration (TDM-4Drespiratoire), une IRM cardiaque et une cartographie du substrat arythmogene (cartographie de voltage en rythme sinusal et cartographie d’activation des tachycardies ventriculaires). Un recalage rigide a ete effectue sur l’ensemble des images. L’amplitude des mouvements cardiaques et respiratoires du volume macroscopique tumoral (presence de calcifications) et de la sonde de defibrillation a ete quantifiee dans les trois directions de l’espace a partir du TDM-4Dcardiaque et de la TDM-4Drespiratoire. Le volume macroscopique tumoral a ete delinee sur les phases diastoliques et systoliques de la TDM-4Dcardiaque permettant d’en deduire un volume cible interne cardiaque. Resultats et analyse statistique L’amplitude des mouvements cardiaques et respiratoires du volume macroscopique tumoral et de la sonde de defibrillation sont presentes dans le Tableau 1 Les battements cardiaques induisent donc des mouvements du volume macroscopique tumoral d’amplitudes proches de ceux induits par la respiration. Le mouvement respiratoire du volume macroscopique tumoral n’est pas identique au mouvement respiratoire de la sonde de defibrillation. Le volume macroscopique tumoral etait de 15,9 cm3 et 17,7 cm3 sur les phases diastoliques et systoliques, respectivement. Le volume cible interne correspondant etait de 20,7 cm3. Ces differences de volume montrent une deformation significative du volume macroscopique tumoral et la necessite d’une imagerie quadridimensionnelle permettant de caracteriser la dynamique cardiaque. Conclusion Cette etude preliminaire, basee sur un seul patient, montre que la definition optimale du volume cible en tachycardie ventriculaire refractaire implique l’acquisition d’images quadridimensionnelles cardiaque et respiratoire. En cas d’implementation de methodes actives de gestion des mouvements respiratoires a l’appareil de traitement, l’utilisation de la sonde de defibrillation comme repere peut induire potentiellement des imprecisions de ciblage qu’il est important de considerer dans le calcul des marges du volume cible previsionnel.

Purpose Literature review reporting results of salvage brachytherapy and stereotactic body radiotherapy for prostate recurrence only after radiotherapy for prostate cancer. Materials and methods A total of 38 studies (including at least 15 patients per study) were analysed: 19 using low-dose-rate brachytherapy, nine high-dose-rate brachytherapy and ten stereotactic body radiotherapy. Only five studies were prospective. The median numbers of patients were 30 for low-dose-rate brachytherapy, 34 for high-dose-rate brachytherapy, and 30 for stereotactic body radiotherapy. The median follow-up were 47 months for low-dose-rate brachytherapy, 36 months for high-dose-rate brachytherapy and 21 months for stereotactic body radiotherapy. Results Late genitourinary toxicity rates ranged, for grade 2: from 4 to 42% for low-dose-rate brachytherapy, from 7 to 54% for high-dose-rate brachytherapy and from 3 to 20% for stereotactic body radiotherapy, and for grade 3 or above: from 0 to 24% for low-dose-rate brachytherapy, from 0 to 13% for high-dose-rate brachytherapy and from 0 to 3% for grade 3 or above (except 12% in one study) for stereotactic body radiotherapy. Late gastrointestinal toxicity rates ranged, for grade 2: from 0 to 6% for low-dose-rate brachytherapy, from 0 to 14% for high-dose-rate brachytherapy and from 0 to 11% for stereotactic body radiotherapy, and for grade 3 or above: from 0 to 6% for low-dose-rate brachytherapy, and from 0 to 1% for high-dose-rate brachytherapy and stereotactic body radiotherapy. The 5-year biochemical disease-free survival rates ranged from 20 to 77% for low-dose-rate brachytherapy and from 51 to 68% for high-dose-rate brachytherapy. The 2- and 3-year disease-free survival rates ranged from 40 to 82% for stereotactic body radiotherapy. Prognostic factors of biochemical recurrence have been identified. Conclusion Despite a lack of prospective data, salvage reirradiation for prostate cancer recurrence can be proposed to highly selected patients and tumours. Prospective comparative studies are needed.

International audience; Introduction - Large anatomical variations can be observed during the treatment course intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC), leading to potential dose variations. Adaptive radiotherapy (ART) uses one or several replanning sessions to correct these variations and thus optimize the delivered dose distribution to the daily anatomy of the patient. This review, which is focused on ART in the HNC, aims to identify the various strategies of ART and to estimate the dosimetric and clinical benefits of these strategies. Material and methods - We performed an electronic search of articles published in PubMed/MEDLINE and Science Direct from January 2005 to December 2016. Among a total of 134 articles assessed for eligibility, 29 articles were ultimately retained for the review. Eighteen studies evaluated dosimetric variations without ART, and 11 studies reported the benefits of ART. Results - Eight in silico studies tested a number of replanning sessions, ranging from 1 to 6, aiming primarily to reduce the dose to the parotid glands. The optimal timing for replanning appears to be early during the first two weeks of treatment. Compared to standard IMRT, ART decreases the mean dose to the parotid gland from 0.6 to 6 Gy and the maximum dose to the spinal cord from 0.1 to 4 Gy while improving target coverage and homogeneity in most studies. Only five studies reported the clinical results of ART, and three of those studies included a non-randomized comparison with standard IMRT. These studies suggest a benefit of ART in regard to decreasing xerostomia, increasing quality of life, and increasing local control. Patients with the largest early anatomical and dose variations are the best candidates for ART. Conclusion - ART may decrease toxicity and improve local control for locally advanced HNC. However, randomized trials are necessary to demonstrate the benefit of ART before using the technique in routine practice.

The development of stereotaxic body radiotherapy in the last decade has forced the radiotherapy departments to redouble their efforts in the fields of quality and risk management. For this purpose, increasingly complex and rigorous controls of high performance machines as well as a solid team training must be put in place. Extreme hypofractionation requires both increased vigilance at the treatment desk and well-defined and known procedures. The in place organizations contribute to the control of the risks related to the stereotaxic body radiotherapy machines. The medical presence at the beginning of the treatment fractions has been specified as mandatory in a regulatory way since January 2017. This not only ensures security, but also transmits information to the radiation therapy technicians. At the Eugène-Marquis center, the skills of the technicians for stereotaxic body radiotherapy on two dedicated machines (Cyberknife

The purpose of this paper was to describe local control, overall survival, progression-free survival and toxicity of CyberKnifeRecords of all the patients treated for hepatocellular carcinoma at the Eugene-Marquis cancer centre, Rennes and the Bretonneau hospital, Tours (France), between November 2010 and December 2016, were reviewed. Radiation therapy was performed as a salvage treatment, while awaiting liver transplantation or if no other treatment was possible.One hundred and thirty-six patients were consecutively included in the study. The median follow-up was 13months. Median total dose prescribed, fractionation and overall treatment time were respectively 45Gy, three fractions and 5 days. Overall survival, progression-free survival and local control rates at 1year and 2years were 79.8 % and 63.5 %, 61.3 % and 39.4 %; 94.5 % and 91 %. Two grade 3 acute toxicity events and two grade 4 late toxicity events corresponding to a duodenal ulcer have been reported. Seven patients underwent classic radiation-induced hepatitis and 13 patients showed non-classical radiation-induced hepatitis. Barcelona Clinic Liver Cancer stage, World Health Organisation grade and planning target volume were correlated with overall survival in univariate Cox analysis.Stereotactic body radiation therapy is effective and well-tolerated for inoperable hepatocellular carcinoma or as a bridge to liver transplantation. Toxicity is mainly related to cirrhotic background and requires a selection of patients and strict dose constraints.

Radiation therapy technique and schedules could be adapted to patient's age because of a natural history of prostate cancer perceived as different, taking into account the comorbidities of patients but also a particular tolerance of elderly subjects. Thus, in localized prostate cancer, evaluation of associated diseases is essential before considering a treatment that will be of interest only if the life expectancy is greater than 10 years. When a curative approach is decided, radiotherapy holds a place of choice. Due to the recent results of randomized studies evaluating moderate hypofractionnated radiotherapy, showing a carcinological equivalence compared to a standard fractionation, this reduction in the duration of treatment appears particularly indicated in this elderly population. This approach permits to maintain the quality of life of patients, potentially with lower costs for society. The purpose of this article is to present the results of randomized trials of moderate hypofractionnation and discuss their application in the population of elderly patients with localized prostate cancer.

Intensity-modulated radiation therapy reduces the dose to organs at risk in patients treated for gynecological malignancies. Given the steep dose gradients around the planning target volume, internal movement of organs during treatment may cause a planning target volume underdosage and organs at risk overdosage in case of systematic error. It is therefore important to take into account the movement of the pelvic organs and to investigate potential solutions provided by image-guided radiotherapy. A review of the literature was carried out using the following databases: Medline, Embase, Cochrane Library, Web of Science, Cinahl and Pubmed. Appropriate search strategies for each database were applied based upon the following terms "uterine neoplasms, image-guided radiotherapy, adaptive radiotherapy, organ motion and target volume". These studies show that uterine motion is mainly influenced by bladder filling and by cervix and vaginal vault motion due to rectal filling. Population-based clinical target volume-planning target volume margins are large resulting in unnecessary organs at risk inclusion within the planning target volume, reducing the benefits of intensity-modulated radiotherapy. As pelvic organ motion seems to be patient specific, individualised planning target volume margins and adaptive radiotherapy strategies could allow adequate coverage of the planning target volume and increase organs at risk savings. In this study, we review the different techniques of image-guided radiotherapy and the perspective of adaptive radiotherapy.

During the course of intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC), the delivered dose may differ from the planned dose due to significant anatomical variations. Several st...

International audience; Background and purpose - During head-and-neck (H&N) radiotherapy, the parotid glands (PGs) may be overdosed; thus, a tool is required to monitor the delivered dose. This study aimed to assess the dose accuracy of a patient-specific density assignment method (DAM) for dose calculation to monitor the dose to PGs during treatment. Patients and methods - Forty patients with H&N cancer received an intensity modulated radiation therapy (IMRT), among whom 15 had weekly CTs. Dose distributions were calculated either on the CTs (CT), on one-class CTs (1C-CT, water), or on three-class CTs (3C-CT, water-air-bone). The inter- and intra-patient DAM uncertainties were evaluated by the difference between doses calculated on CT and 1C-CTs or 3C-CTs. PG mean dose (D) and spinal cord maximum dose (D) were considered. The cumulated dose to the PGs was estimated by the mean D of the weekly CTs. Results - The mean (maximum) inter-patient DAM dose uncertainties for the PGs (in cGy) were 23 (75) using 1C-CTs and 12 (50) using 3C-CTs (p ≤ 0.001). For the spinal cord, these uncertainties were 118 (245) and 15 (67; p ≤ 0.001). The mean (maximum) DAM dose uncertainty between cumulated doses calculated on CTs and 3C-CTs was 7 cGy (45 cGy) for the PGs. Considering the difference between the planned and cumulated doses, 53% of the ipsilateral and 80% of the contralateral PGs were overdosed by +3.6 Gy (up to 8.2 Gy) and +1.9 Gy (up to 5.2 Gy), respectively. Conclusion - The uncertainty of the three-class DAM appears to be clinically non-significant (

International audience; Considering recent phase III trials results, moderate hypofractionated radiotherapy can be considered as a standard treatment for low and intermediate risk prostate cancer management. This assessment call for a framework allowing homogeneous and reproducible practices in the different centers using this radiotherapy schedule. The French Genito-Urinary Group (GETUG) provides here recommendations for daily practice of moderate hypofractionated radiotherapy for prostate cancer, with indications, dose, fractionation, pre-treatment planning, volume of interest delineation (target volume and organs at risk) and margins, dose constraints and radiotherapy techniques.

Introduction et but de l’etude Differentes methodes d’apprentissage peuvent etre utilisees pour generer des pseudo-scanographies a partir d’IRM ou de tomographies coniques (cone beam computed tomography, CBCT), permettant un calcul de distribution de dose. L’objectif est d’evaluer des methodes d’apprentissage pour generer des pseudo-scanographies a partir d’IRM et de tomographies coniques. Materiel et methodes Trente-neuf patients ayant une radiotherapie conformationnelle avec modulation d’intensite (RCMI ; delivrant 78 Gy) pour un cancer de la prostate ont eu une scanographie de planification et une IRM en position de traitement. Des pseudo-scanographies ont ete generes a partir de l’IRM par neuf methodes : assignement de densite, atlas, patch et apprentissage profond (par reseau de neurones a convolution [U-Net] ou par reseau antagoniste generatif [GAN], combinant differents parametres). Quarante-quatre patients ayant une RCMI (de 70 Gy) pour un cancer ORL ont eu une scanographie et une tomographie conique hebdomadaire. Des pseudo-scanographies ont ete generees a partir de la tomographie conique par quatre methodes : courbe des unites Hounsfield (UH) densite, assignement de densite, recalage deformable et apprentissage profond. L’evaluation a porte sur la comparaison entre scanographie (de reference) et pseudo-scanographie. Les criteres de jugement etaient : l’image (unites Hounsfield), la dose et le temps de calcul. Resultats et analyse statistique Concernant les criteres « image » : les methodes les plus precises sont l’ apprentissage profond (reseau antagoniste generatif). Concernant les criteres dosimetriques : les incertitudes sont globalement tres faibles. Elles sont significativement plus faibles pour les methodes d’apprentissage profond et en particulier par reseau antagoniste generatif. Pour la methode par reseau antagoniste generatif appliquee a l’IRM pelvienne, les incertitudes moyennes etaient : de 0,6 % pour le volume prostatique recevant 95 % de la dose prescrite, 0,5 % pour le volume rectal recevant 70 Gy, et 0,1 % pour le volume vesical recevant 50 Gy. Pour la methode par reseau antagoniste generatif sur la tomographie conique ORL, ces incertitudes etaient de 8 et 5 cGy pour la dose moyenne parotidienne homolaterale et controlaterale. Les temps de calcul les plus courts sont en faveur des methodes d’apprentissage profond (15 s). Conclusion Dans le but de calculer une dose sur une pseudo-scanographie generee a partir d’une IRM ou d’une tomographie conique, les methodes d’apprentissage profond (en particulier par reseau antagoniste generatif) conduisent a de faibles incertitudes d’images (HU) et de dose, associees a un temps de calcul tres court. La mise en œuvre clinique doit etre associee a une assurance qualite tres rigoureuse.

National audience; The development of both image-guided and intensity-modulated radiotherapy has underlined the question of treatment adaptation to anatomical and/or biological changes occurring during radiotherapy course and modifying delivered dose to the patient. Adaptive radiotherapy has been introduced when several plans are used to treat a patient during radiotherapy. Adaptation may be performed online, offline or in a hybrid way. New images of the patient are needed for adaptive radiotherapy to perform many processes: image registration, segmentation and evaluation of cumulative dose. Deformable image registration methods are generally used to image registration and contours propagation. Fraction and cumulative dose evaluations use deformable image registration methods or more complex methods based on Monte-Carlo calculation. These methods have uncertainties and have to be evaluated. However, evaluation and validation tools are still being developed. The physicist's mission is to ensure that every new technology, such as adaptive radiotherapy, is deployed with highest safety, by technical validation and by implementing a specific quality assurance program. Adaptive radiotherapy implementation still raises many questions, so its potential clinical application requires great caution and should be carefully explored in prospective clinical trials.

Image-guided radiation therapy consists in acquiring in-room images to improve patient and mainly tumour set up accuracy. Many devices based on ionising or non-ionising radiations were designed in recent years. The use of such devices is of major importance in the management of patient radiotherapy courses. Those imaging sessions require to clearly define procedures in each radiotherapy department (image modality, acquisition frequency, corrective action, staff training and tasks). A quick review of the different existing image-guided radiation therapy devices is presented. In addition, the results of a French national survey about image-guided radiation therapy are presented: the survey is about both equipment and procedures. A total of 57 radiotherapy departments have participated, representing more than 160 treatment devices. About three linear accelerators out of four are equipped with an image-guiding device. The most common equipment is the CBCT system. Most centres have set up training sessions for the technicians to allow them to analyse online daily images. The management of in-room imaging dose is still under investigation, but many centres use an accounting scheme. While the devices are used to adjust the positioning of patients, in more than half of the centres, the practice had an impact on the choice of clinical and planning target volume margins. This survey led to an inventory in 2015, and could be renewed in some years.

Image-guided radiotherapy (IGRT) aims to take into account the anatomical variations occurring during the course of radiotherapy, by direct or indirect visualization of the target volume followed by a corrective action. The movements of the target, or at least the set-up errors are corrected by moving the treatment table, corresponding to the simplest and most validated IGRT modality in a standard practice. The deformations of the target volume and organs at risk are however much more common, and unfortunately much more complicated to consider, requiring multiple planning before or during the treatment, corresponding to the adaptive radiotherapy strategies. The planning target volume must be carefully chosen according to these anatomic variations. This article reviews the modalities of IGRT, standard or under evaluation, according to the different tumour sites.

In 2008, the French national society of radiation oncology (SFRO) and the association for radiation oncology continued education (AFCOR) created Siriade, an e-learning website dedicated to contouring.Between 2015 and 2017, this platform was updated using the latest digital online tools available. Two main sections were needed: a theoretical part and another section of online workshops.Teaching courses are available as online commented videos, available on demand. The practical section of the website is an online contouring workshop that automatically generates a report quantifying the quality of the user's delineation compared with the experts'.Siriade 2.0 is an innovating digital tool for radiation oncology initial and continuous education.

Quality of life is a major issue for good prognostic prostate cancer, for which brachytherapy is one of the reference treatments. Stereotactic Body Radiotherapy (SBRT) is a recent alternative however not yet validated as a standard treatment. This review of the literature reports and compares the toxicities and the quality of life, either after exclusive brachytherapy with iodine 125 or after SBRT. The comparison is made with the limitations of the absence of randomized trial comparing the two treatment techniques. Acute toxicity appears to be lower after SBRT compared to brachytherapy (from 10 to 40 % versus 30 to 40 %, respectively). Conversely, acute and late gastrointestinal toxicity (from 0 to 21 % and from 0 to 10 % of grade 2, respectively) appears more frequent with SBRT. Late urinary toxicity seems identical between both techniques (from 20 to 30 % of grade 2), with a possible urinary flare syndrome. Both treatments have an impact on erectile dysfunction, although it is not possible to conclude that a technique is superior because of the limited data on SBRT. SBRT has better bowel and urinary (irritation or obstruction) quality of life scores than brachytherapy; while sexual and urinary incontinence remain the same. The absence of randomized trial comparing SBRT with brachytherapy for prostate cancers does not allow to conclude on the superiority of one technique over another, thus justifying a phase III medicoeconomic evaluation.

In external beam radiotherapy, the dose planning is currently based on computed tomography (CT) images. A relation between Hounsfield numbers and electron densities (or mass densities) is necessary for dose calculation taking heterogeneities into account. In image-guided radiotherapy process, the cone beam CT is classically used for tissue visualization and registration. Cone beam CT for dose calculation is also attractive in dose reporting/monitoring perspectives and particularly in a context of dose-guided adaptive radiotherapy. The accuracy of cone beam CT-based dose calculation is limited by image characteristics such as quality, Hounsfield numbers consistency and restrictive sizes of volume acquisition. The analysis of the literature identifies three kinds of strategies for cone beam CT-based dose calculation: establishment of Hounsfield numbers versus densities curves, density override to regions of interest, and deformable registration between CT and cone beam CT images. Literature results show that discrepancies between the reference CT-based dose calculation and the cone beam CT-based dose calculation are often lower than 3%, regardless of the method. However, they can also reach 10% with unsuitable method. Even if the accuracy of the cone beam CT-based dose calculation is independent of the method, some strategies are promising but need improvements in the automating process for a routine implementation.

International audience; The pencil beam method is commonly used for dose calculations in intensity-modulated radiation therapy (IMRT). In this study, we have proposed a novel pencil model for calculating photon dose distributions in heterogeneous media. To avoid any oblique kernel-related bias and reduce computation time, dose distributions were computed in a spherical coordinate system based on the pencil kernels of different distances from source to surface (DSS). We employed two different dose calculation methods: the superposition method and the fast Fourier transform convolution (FFTC) method. In order to render the superposition method more accurate, we scaled the depth-directed component by moving the position of the entry point and altering the DSS value for a given beamlet. The lateral components were thus directly corrected by the density scaling method along the spherical shell without taking the densities from the previous layers into account. Significant computation time could be saved by performing the FFTC calculations on each spherical shell, disregarding density changes in the lateral direction. The proposed methods were tested on several phantoms, including lung- and bone-type heterogeneities. We compared them with Monte Carlo (MC) simulation for several field sizes with 6 MV photon beams. Our results revealed mean absolute deviations

Resume L’identification de la technique optimale d’irradiation prostatique repose principalement sur des donnees methodologiques correspondant a des etudes dosimetriques et cliniques, bien que les etudes de phase III comparant differentes techniques soient cependant quasi inexistantes. La faisabilite des techniques innovantes depend aussi des ressources humaines et techniques des services de radiotherapie, du cout des traitements a la fois du point de vue de la societe, du patient et du therapeute, et finalement du choix du patient informe objectivement. L’histoire naturelle tres lente du cancer de prostate conduit a considerer un critere de jugement principal de recidive biochimique discutable. Un suivi important est necessaire pour evaluer la toxicite urinaire, potentiellement de survenue tres tardive. La radiotherapie conformationnelle avec modulation d’intensite (RCMI) guidee par l’image est recommandee en cas de haute dose dans la prostate (76 Gy et plus), d’irradiation des aires ganglionnaires ou d’irradiation hypofractionnee. Pour les tumeurs de bas risque, la strategie therapeutique vise prioritairement a preserver la qualite de vie et minimiser les couts. La radiotherapie stereotaxique proposant un hypofractionnement extreme montre des resultats prometteurs avec un recul limite. Elle est en cours d’evaluation dans des essais de phase III. L’irradiation focale est a un stade de faisabilite. Pour les tumeurs de risque intermediaire et de haut risque, l’objectif est d’augmenter le taux de controle locoregional en limitant la toxicite. La RCMI guidee par l’image permet pour ces tumeurs ainsi, soit une strategie d’escalade de dose bien validee pour les tumeurs de risque intermediaire, soit un hypofractionnement modere, qui n’est cependant pas encore un standard therapeutique. Ces techniques conjuguees permettent aussi l’irradiation de larges volumes ganglionnaires a dose elevee ou un complement d’irradiation dans la tumeur intra-prostatique, eventuellement dans le cadre d’une irradiation avec boost integre, dont la faisabilite est demontree.

Objectif de l’etude L’objectif de l’etude etait d’ecrire le controle local, la survie globale, la survie sans progression et la toxicite de la radiotherapie stereotaxique par CyberKnife® et de rechercher les facteurs pronostiques associes dans le traitement des carcinomes hepatocellulaires. Materiel et methode Il s’agit d’une etude observationnelle retrospective et multicentrique menee au centre Eugene-Marquis a Rennes et au centre hospitalier universitaire Bretonneau a Tours entre novembre 2010 et decembre 2016. Le traitement a ete realise en situation de rattrapage apres chimioembolisation transarterielle, et/ou radiofrequence ablative et/ou resection chirurgicale ; en traitement d’attente d’une transplantation hepatique ou en traitement de recours si aucune autre alternative therapeutique n’etait possible. Resultats En tout, 136 patients ont ete consecutivement inclus dans l’etude. Le suivi median a ete de 13 mois. La dose mediane totale prescrite etait de 45 Gy, avec un fractionnement median de trois seances et un etalement median de cinq jours. Les taux de survie globale, de survie sans progression et de controle local a 1 an et 2 ans etaient respectivement de 79,8 % et 63,5 %, de 61,3 % et 39,4 %, de 94,5 % et 91 %. Il y avait chez tous les patients ayant eu une greffe une reponse histologique sur la lesion traitee. Deux evenements de toxicite aigue de grade 3 et deux evenements de toxicite tardive de grade 4 correspondant a un ulcere duodenal ont ete rapportes. Vingt patients ont souffert d’une hepatite radio-induite, classique pour sept et non classique pour 13. Le stade Barcelona Clinic Liver Cancer (BCLC), celui de l’OMS et le volume cible previsionnel etaient correles avec la survie globale en analyse unifactorielle. Conclusion La radiotherapie stereotaxique est un traitement efficace en termes de controle local, peu invasif et bien tolere. La toxicite est principalement liee au terrain cirrhotique et implique une selection des patients et des contraintes de doses strictes dans les organes a risque. La radiotherapie stereotaxique devrait s’inscrire comme une nouvelle arme therapeutique dans le cadre du traitement des carcinomes hepatocellulaires inoperables ou en attente de transplantation.

Objectif de l’etude Realiser un calcul de dose a partir d’une IRM implique de generer une pseudo-scanographie. L’objectif de cette etude etait de comparer trois methodes pour generer une pseudo-scanographie : une methode basee sur l’utilisation de patches (patch-based method, PBM), une methode atlas (atlas-based method, ABM) et une methode d’assignation de densite (bulk density method, BDM). Materiel et methode Trente-neuf patients pris en charge par radiotherapie conformationnelle avec modulation d’intensite (de 78 Gy) pour un cancer de la prostate ont ete consideres. Chaque patient a eu une IRM ponderee en T2 et une scanographie de planification. A partir des IRM, des pseudo-scanographies ont ete generes par es trois methodes. Ces methodes ont ete comparees en termes d’image et de dose. Les criteres images etaient l’erreur absolue moyenne et l’erreur moyenne des differences entre les pseudo-scanographies et les scanographies de planification. Les criteres dosimetriques etaient les moyennes des ecarts absolus des histogrammes dose–volume (pseudo-scanographies contre scanographie de planification), pour le volume cible previsionnel et les organes a risques. Des analyses gamma en trois dimensions (locale, 1 %/1 mm) et des tests de Wilcoxon ont ete realises. Resultats Une erreur absolue moyenne de 41,1 Hounsfield units (HU) et une erreur moyenne de –1,1 HU ont ete obtenues pour la methode utilisant des patches. Ces valeurs sont significativement plus faibles que celles de la methode basee sur l’atlas (43,8 HU et–7,8 HU) et celle basee sur l’assignation de densite (98,7 HU et–17,8 HU). Pour la methode basee sur l’utilisation de patches, les differences moyennes d’histogramme dose–volume etaient de 0,7 % le V95 % du volume cible previsionnel (Vx : volume recevant × % de la dose prescrite), 0,5 % pour le V70Gy du rectum et 0,2 % pour le V50Gy de la vessie. La methode basee sur l’utilisation de patches a montre des differences d’histogramme dose–volume significatives (pseudo-scanographie contre scanographie de planification) pour le volume cible previsionnel (de 70 a 78 Gy), le rectum (de 8,5 a 29 Gy, de 40 a 48 Gy, et de 61 a 73 Gy) et la vessie (de 12 a 78 Gy). Ces differences etaient plus faibles pour la methode atlas et celle basee sur l’assignation de densite. Les taux de passe gamma etaient significativement plus elevees pour la methode basee sur l’utilisation de patches (99,5 %) que pour la methode atlas (94,9 %) et celle basee sur l’assignation de densite (96,1 %). Conclusion Dans le but de calculer une dose sur une pseudo-scanographie genere a partir d’IRM, les trois methodes testees conduisent a des incertitudes faibles (superieures a > 1 %) et donc cliniquement acceptables. La methode la plus precise est celle utilisant des patches.

International audience