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Simple Summary Although the use of stereotactic body radiation therapy (SBRT) in the management of hepatocellular carcinoma (HCC) remains unclear, it is a therapeutic option often considered in patients not eligible to or recurring after other local therapies. Liver SBRT can be delivered using a wide range of techniques and linear accelerators. We report the first evaluation for HCC of SBRT using volumetric modulated arc therapy (VMAT) and real-time adaptive tumor gating, which is a mainly completely non-invasive procedure (no fiducial markers for 65.2% of the patients). Our study showed that this SBRT technique has very favorable outcomes with optimal local control and a low toxicity rate. Abstract Liver SBRT is a therapeutic option for the treatment of HCC in patients not eligible for other local therapies. We retrospectively report the outcomes of a cohort of consecutive patients treated with SBRT for HCC at the Montpellier Cancer Institute. Between March 2013 and December 2018, 66 patients were treated with image-guided liver SBRT using VMAT and real-time adaptive tumor gating in our institute. The main endpoints considered in this study were local control, disease-free survival, overall survival, and toxicity. The median follow-up was 16.8 months. About 66.7% had prior liver treatment. Most patients received 50 Gy in five fractions of 10 Gy. No patient had local recurrence. Overall survival and disease-free survival were, respectively, 83.9% and 46.7% at one year. In multivariate analysis, the diameter of the lesions was a significant prognostic factor associated with disease-free survival (HR = 2.57 (1.19–5.53) p = 0.02). Regarding overall survival, the volume of PTV was associated with lower overall survival (HR = 2.84 (1.14–7.08) p = 0.025). No grade 3 toxicity was observed. One patient developed a grade 4 gastric ulcer, despite the dose constraints being respected. Image-guided liver SBRT with VMAT is an effective and safe treatment in patients with inoperable HCC, even in heavily pre-treated patients. Further prospective evaluation will help to clarify the role of SBRT in the management of HCC patients.

To evaluate our long-term experience on one-day breast intraoperative radiotherapy (IORT) given as sole radiation treatment to selected patients with breast cancer.Inclusion criteria of INTRAOBS study (prospective observational study) were: ER+ T1N0 unifocal ductal carcinoma; absence of lymphovascular invasion or of extensive intraductal component (Scarff-Bloom-Richardson grade III and HER2+++ excluded). Two different linacs were used (20Gy/1 fraction): one dedicated electron linac (October 2011), and afterwards a mobile linac (50kV photons). The primary endpoint was the local recurrence rate (=ipsilateral breast cancer recurrences number). Secondary endpoints were recurrence-free survival (RFS), overall and specific survival, cosmetic results, and patient satisfaction.Of the present pre-planned analysis for the first 200 patients (median age: 68 years; range, 59-87 years) who received IORT between January 2010 and October 2014 (median follow-up of 53.4 months). A total of 193 patients were still alive. The local recurrence rate was 2.5% (n=5). The 1- and 5-year local RFS rates were 100% and 95.2%, respectively. At 12 months post-surgery, satisfaction about IORT was excellent for 86.9% of patients. Cosmetic results were considered by patients and physicians as good or very good in 89.4% and 97.3% of cases, respectively.IORT for selected patients with breast cancer shows low recurrence rates, good cosmetic outcomes and excellent satisfaction.

Introduction et but de l’etude ViewRay a termine l’installation d’un MRIdian® a l’institut du cancer de Montpellier en septembre 2019. La mise en œuvre de cette machine hybride integrant un accelerateur lineaire dans un champ magnetique apporte des problematiques physiques inedites auxquelles il a fallu repondre avant de commencer les traitements. Nous detaillons ici les differentes evaluations realisees avant la mise en route clinique du systeme. Materiel et methodes L’impact sur nos instruments de mesures, specifiques a la presence d’un champ magnetique ainsi qu’a la conception du MRIdian, a ete etudiee. Differents prototypes de cuves motorisees compatibles avec l’IRM ont ete utilises pour la calibration du debit de dose et les mesures de dose relative dans l’eau. L’absence d’imageur portal conduit a l’utilisation de films radiochromiques pour les controles mecaniques de l’isocentre ou du collimateur multilames. La latence du systeme et le cumul de la dose delivree ont ete controles a l’aide d’un fantome mobile afin de verifier la bonne synchronisation entre le declenchement du faisceau et la position detectee de l’organe mobile. D’autre part, le programme d’assurance qualite mis en place, compatibles avec les textes de loi en vigueur, a ete adapte aux caracteristiques de la machine. Resultats et analyse statistique Le champ magnetique de 0,35 T avait une influence negligeable sur les detecteurs utilises : SemiFlex 3D (PTW 31021) et microDiamond (PTW 60019). Les profils lateraux et rendements en profondeur, mesures a 80 SSD ont montre une tres bonne correspondance avec les simulations Monte-Carlo du systeme de planification des traitements avant et apres la montee du champ magnetique. Avec une resolution de 1 mm et une incertitude de 1 % comme parametres de calcul et des champs allant de 0,415 cm2 a la taille maximale, le plus grand ecart de dose locale trouve a ete de 1,3 % pour le rendement en profondeur du plus grand champ a 20 cm de profondeur. Pour les profils, la correspondance est parfaite avec un maximum d’ecart de dose locale de 4,1 % en dehors du champ d’irradiation. Les tailles de champs mesurees montrent un ecart maximal de 0,8 mm en lateral et 0,6 mm en longitudinal. Les facteurs de sortie, mesures a 85 cm source to skin distance (SSD), ont mis en evidence une difference maximale de ±0,8 % pour les champs superieurs a 1,6 cm de cote, et de −4,7 % pour le plus petit champ de 0,8 cm, par rapport au calcul. L’utilisation de films Gafchromiques pour la realisation de tests starshot et picket fence a mis en evidence une precision mecanique de l’isocentre radiatif de 1,1 mm, ainsi qu’une correspondance avec l’isocentre d’imagerie inferieure a 0,9 mm. Le positionnement des lames du collimateur multilames est quant a lui precis a ± 0,8 mm. Enfin, le controle du tracking a donne de bons resultats, avec une latence de 0,2 s et une dose cumulee proche de la dose sans tracking (0,3 % d’ecart). Conclusion Les differents points dosimetriques et mecaniques verifies sont en accord avec les donnees constructeur. La modelisation du systeme de planification des traitements reflete bien les caracteristiques de la machine. Un processus de controle qualite mis en place depuis l’installation de la machine montre des resultats stables jusqu’a ce jour.

International audience; Background and purpose: To assess the long-term outcomes of patients with squamous cell carcinoma of the anal canal (SCCAC) treated with Intensity-Modulated Radiation Therapy (IMRT).Material and methods: From 2007 to 2015, 193 patients were treated by IMRT for SCCAC. Radiotherapy delivered 45 Gy in 1.8 Gy daily-fractions to the primary tumor and elective nodal areas, immediately followed by a boost of 14.4-20 Gy to the primary tumor and involved nodes. Concurrent chemotherapy with 5-FU-mitomycin (MMC) or cisplatin was added for locally advanced tumors. Survivals were estimated by Kaplan-Meier method. Locoregional (LR) relapses were precisely assessed. Prognostic factors were evaluated by uni- and multivariate analyses. Late toxicity was scored according to the Common Toxicity Criteria for Adverse Events v4.0.Results: Median follow-up was 70 months (range, 1-131). Forty-nine men (25%) and 144 women (75%) were analyzed. Median age was 62 years. Tumor stages were I, II, III and IV in 7%, 24%, 63% and 6% of cases, respectively. Chemotherapy was delivered in 167 patients (87%), mainly MMC (80%). Five-year OS, DFS, CFS and LR control rates were 74%, 68%, 66% and 85%, respectively. Forty-one patients (21%) had a relapse: 22 were LR, mostly in-field (68%). Predictors for LR failure were exclusive radiotherapy, chemotherapy lacking MMC and treatment breaks >3 days. Overall late toxicity ≥grade 2 occurred in 43% of patients, with 24% grade 3 and one case of grade 4 (hematuria).Conclusion: CRT with IMRT assures excellent local control in locally advanced SCCAC with manageable long-term toxicity. Multicentric prospective trials are required to reinforce those results.

Introduction et but de l’etude Depuis octobre 2019, l’Institut du cancer de Montpellier (ICM) traite certains cancers comme ceux du pancreas, du foie et les recidives de cancer de la prostate avec un accelerateur lineaire couple a un IRM de 0,35 T, le MRIdian® (ViewRay® Technologies, Inc.). Cet appareil permet une bonne visualisation des tissus mous, le suivi en temps reel d’un volume cible, et la possibilite de traitement adaptatif quotidien. La qualite des images joue donc un role primordial. Nous detaillons ici l’acceptance et la mise en place des controles de la partie IRM de l’appareil MRIdian®. Materiel et methodes L’homogeneite du champ magnetique en fonction de l’angle du bras, ainsi que le rapport signal sur bruit et l’uniformite des antennes ont ete mesures avec un fantome homogene dans les trois plans. Tous les controles ont ete effectues avec l’angle de bras produisant l’homogeneite la moins bonne. Les recommandations de l’American College of Radiology (ACR) et leur fantome ont ete utilises pour controler les performances globales de l’IRM. L’integrite spatiale a ete mesuree dans les trois plans a plusieurs positions autour de l’isocentre. Le bruit sur les images avec et sans la presence de la radiofrequence externe du faisceau a ete evalue en fonction de l’angle du bras, tout comme la presence d’eventuels artefacts en mode cine sur les coupes sagittales a l’isocentre (field of view [FOV] minimum de 30 cm) et a ± 12,5 cm (FOV minimum de 16,6 cm). Resultats et analyse statistique L’homogeneite du champ magnetique en fonction de l’angle du bras etait dans la tolerance de 5 ppm avec une valeur maximale de 3,8 ppm a 90°. Les resultats de rapport signal sur bruit etaient de 13,2 en moyenne pour l’antenne interne, 42 en moyenne pour les antennes corps et tete, et etaient superieurs aux tolerances du constructeur (12 et 30 respectivement). Il en etait de meme pour l’uniformite (moyenne de 66,9 % pour 60 % demande pour l’antenne interne, 66,7 % pour 50 % demande pour les autres antennes). Les resultats des tests de l’ACR etaient dans les specifications ( Tableau 1 ). Pour l’integrite spatiale, tous les points des images situes dans le FOV de 20 cm se situaient a moins de 1 mm de leur position attendue, et ceux situes entre 20 et 35 cm etaient a moins de 2 mm. Le rapport entre les deviations standard du bruit de l’image avec et sans la radiofrequence de l’accelerateur lineaire a atteint un maximum de 3,5 % a 240°, pour une tolerance de 20 %. Enfin, dans les images cine en coupe sagittale, aucun artefact ne se situait dans le FOV minimum associe. Un programme d’assurance qualite d’imagerie a ete mis en place afin de suivre l’evolution de ces valeurs. Conclusion L’acceptance du systeme MRIdian® a ete realisee par le constructeur en presence des physiciens referents. Les controles de qualite periodiques sont bases sur les recommandations du constructeur. A chaque intervention sur un element de l’IRM, l’homogeneite de champ magnetique en fonction de l’angle de bras doit etre effectuee. Le controle de l’ACR n’est pas adapte pour un IRM a bas champ car il est chronophage et n’utilise pas la sequence unique true fast imaging with steady state precession (TrueFISP) utilisee cliniquement pour la prise en charge des patients.

Background and purpose: We performed a multi-centre intercomparison of VMAT dose planning and pretreatment verification. The aims were to analyse the dose plans in terms of dosimetric quality and deliverability, and to validate whether in-house pre-treatment verification results agreed with those of an external audit. Materials and methods: The nine participating centres encompassed different machines, equipment, and methodologies. Two mock cases (prostate and head and neck) were planned using one and two arcs. A plan quality index was defined to compare the plans and different complexity indices were calculated to check their deliverability. We compared gamma index pass rates using the centre's equipment and methodology to those of an external audit (global 3D gamma, absolute dose differences, 10% of maximum dose threshold). Log-file analysis was performed to look for delivery errors. Results: All centres fulfilled the dosimetric goals but plan quality and delivery complexity were heterogeneous and uncorrelated, depending on the manufacturer and the planner's methodology. Pretreatment verifications results were within tolerance in all cases for gamma 3%-3 mm evaluation. Nevertheless, differences between the external audit and in-house measurements arose due to different equipment or methodology, especially for 2%-2 mm criteria with differences up to 20%. No correlation was found between complexity indices and verification results amongst centres. Conclusions: All plans fulfilled dosimetric constraints, but plan quality and complexity did not correlate and were strongly dependent on the planner and the vendor. In-house measurements cannot completely replace external audits for credentialing. (C) 2017 Elsevier B.V. All rights reserved.

Surgery (radical cystectomy) is the standard treatment of muscle-invasive bladder cancer. Radiochemotherapy has risen as an alternative treatment option to surgery as part as organ-sparing combined modality treatment or for patients unfit for surgery. Radiochemotherapy achieves 5-year bladder intact survival of 40 to 65% and 5-year overall survival of 40 to 50% with excellent quality of life. This article introduces the French recommendations for radiotherapy of bladder cancer: indications, exams, technique, dosimetry, delivery and image guidance.

Resume La radiotherapie represente une arme therapeutique indiscutable dans les cancers localises de la prostate. Les developpements techniques de ces dernieres annees ont permis l’evolution vers une radiotherapie de conformation tridimensionnelle offrant une meilleure adaptation de la distribution de dose a la forme des volumes cibles. Ainsi, les organes a risque sont mieux preserves tout en delivrant la dose requise au volume cible, avec une augmentation de la dose totale potentielle. Ceci necessite une parfaite connaissance de la radio-anatomie de la prostate, de l’histoire naturelle de ce cancer, mais egalement de la balistique et de la dosimetrie delivree. L’objectif de ce travail est de preciser les particularites epidemiologiques et radio-anatomiques de ce type de tumeur ainsi que les modalites d’irradiation conformationnelle illustrees par un cas clinique.

More than one third of patients with localized prostate cancer at diagnosis who receive radical prostatectomy have histologically extraprostatic disease. Three randomized trials have demonstrated a significant benefit of postoperative radiotherapy for these patients in terms of biochemical progression-free survival, overall survival or metastasis-free survival in function of each study, at the cost of moderate acute and late toxicity. The technical developments of recent years have enabled the evolution of a three-dimensional conformal radiotherapy, with better adaptation of the dose distribution to the shape of target volumes to preserve organs at risk while delivering the required dose volume target. This requires a thorough knowledge of the prostate cancer radioanatomy, ballistics and dosimetry. Purpose of this work was to specify epidemiological and radioanatomy characteristics for this tumor type and conformal radiation modalities illustrated by a case report.

Cancers of the paranasal sinuses are rare tumors, with treatment based on a multidisciplinary approach. Surgery and radiation therapy, possibly associated with chemotherapy are used to obtain 5 years specific survival rate of 60-70 %. Advances in radiotherapy, including the use of imaging for 3D conformal approach require precise knowledge of the radioanatomy for this type of tumor to determine the different volumes of interest. Purpose of this study was to specify radioanatomy and conformal radiation modalities for cancers of the sinuses, and is illustrated by a case report.

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.

Resume Par son approche de dosimetrie inverse, la radiotherapie de conformation par modulation d’intensite (RCMI) a revolutionne la delivrance de dose en radiotherapie externe. La conformation des isodoses aux volumes cibles et la protection des organes critiques ont autorise des possibilites de traitement jusqu’alors impossibles en conformationel 3D (RC3D). Cependant, le temps necessaire a la delivrance en RCMI etait parfois augmente pour certaines localisations par rapport a la RC3D. Afin de pallier cette limite, nous avons teste et developpe depuis 2007, en partenariat avec la societe Varian, une solution d’arctherapie volumetrique modulee denommee RapidArc ® . Une definition de la technique, les resultats des plans dosimetriques et de controle de qualite des 142 premiers patients traites depuis novembre 2008 sont presentes dans cette revue.

Resume Objectif de l’etude. – Rapporter notre experience sur la planification et la toxicite aigue d’une radiotherapie de conformation avec modulation d’intensite (RCMI) chez 16 patients atteints d’un cancer localise de la prostate. Patients et methodes. – Entre mars 2001 et octobre 2002, 16 patients ont ete traites par radiotherapie de conformation avec modulation d’intensite. La planification a ete realisee selon une dosimetrie inverse. Les faisceaux ont ete modules en intensite grâce a un collimateur multilame dynamique. Tous les patients ont recu l’ensemble du traitement sous forme de RCMI jusqu’a une dose prescrite de 78 Gy. Tous les plans de traitement de RCMI ont ete compares a ceux d’une radiotherapie de conformation tridimensionnelle. La toxicite aigue a ete evaluee selon l’echelle du CTCAE version 3.0 (common toxicity criteria for adverse events). Une correlation statistique a ete recherchee entre le volume rectal ou vesical irradie et la toxicite aigue observee. Resultats. –Dans les deux cas (radiotherapie conformationnelle et RCMI), 95 % du PTV2 (volume cible previsionnel 2) a recu une dose superieure a 76 Gy et le benefice apporte par le traitement avec modulation d’intensite est negligeable en ce qui concerne le PTV2. L’analyse de la moyenne des histogrammes dose–volume obtenus pour le PTV2 avec la RCMI et radiotherapie conformationnelle a montre tres peu de difference entre les deux techniques de traitement. Dans les deux cas, les contraintes du protocole Getug 06 (groupe d’etudes des tumeurs urogenitales) etaient largement respectees. Le traitement avec modulation d’intensite permettait toutefois d’ameliorer l’homogeneite de la dose recue par le PTV2, qui etait de 7,5 % avec la RCMI au lieu de 9 % avec la radiotherapie conformationnelle. La dose recue par 95 % du PTV1 etait superieure de plus de 5 Gy avec la RCMI par rapport a la radiotherapie conformationnelle. Une epargne des parois rectales et vesicales a ete mise en evidence par la methode de la RCMI. Le benefice devenait non negligeable en dessous de 75 Gy pour la paroi vesicale. De la meme facon, pour la paroi rectale, l’apport de la modulation d’intensite devenait sensible pour des doses inferieures a 70 Gy. Pendant la radiotherapie, respectivement quatre patients sur 16 (25 %) et cinq patients sur 16 (31 %) ont souffert d’une toxicite rectale et vesicale de grade 2. Aucune toxicite rectale ou vesicale de grade 3 n’a ete observee. La correlation entre la dose recue par 50 % du volume rectal irradie et la toxicite aigue observee n’a pas atteint le seuil de signification, mais en etait tres proche (p = 0,09). Conclusion. – La RCMI dans les cancers localises de la prostate est faisable en pratique quotidienne dans notre centre sans toxicite aigue rectale ou vesicale de grade 3. Un suivi a plus long terme et sur un nombre de patients plus important est necessaire pour evaluer l’efficacite antitumorale.

Introduction Intravenous contrast agent injection during the patient CT simulation facilitates radiotherapy contouring in the case of head and neck cancers. However, the image contrast enhancement may introduce discrepancy between the planned and delivered dose. The aim of this retrospective study is to quantify the variations of Hounsfield unites (HU) and to investigate their effect on Volumetric Modulated Arc Therapy (VMAT) dose distributions. Material and methods Ten patients previously treated by VMAT techniques with identical dose levels (70/60/50 Gy) were selected. For each patient, two CT scans were performed, 2 min. (CT inj ) and 12 min. (CT delay ) after Iomeron® 350 biphasic intravenous injection (60 mL, 1 mL/s followed by 90 mL, 2 mL/s after 30 s). The treatment planning (optimization and calculation) was performed with CT inj using the Eclipse TPS and Acuros XB® algorithm. Two other treatment plans were recalculated with the same parameters and CT delay . The mean HU and the iodine distribution were compared between the two scan images in the PTV50, the parotids and the thyroid. A dosimetric comparison using dose-volume histograms in target volumes and OAR (thyroid, parotids) was performed. The maximum (D 2% ), minimum (D 98% ) and median (D 50% ) doses were registered. Results The maximum HU average difference over all the patients was observed in the thyroid (81.37 ± 36.01 HU) followed by the PTV50 (10.76 pm 15.70 HU) and the parotids (9.39 ± 16.01 HU). The differences observed with Acuros® algorithm were below 0.2% for D 2% , D 98% et D 50% in target volumes and 0.31% in OAR. Conclusion This study shows that the use of intravenous contrast during CT simulation does not significantly affect dose calculation in head and neck VMAT plans using Acuros® algorithm.

The aim of this study was to treat carcinoembryonic antigen (CEA)-expressing pancreatic carcinoma cells with tumour necrosis factor alpha (TNFalpha) and simultaneous radiation therapy (RT), using a bispecific antibody (BAb) anti-TNFalpha/anti-CEA. TNFalpha used alone produced a dose-dependent inhibition of the clonogenic capacity of the cultured cells. Flow cytometry analysis of cell cycle progression confirmed the accumulation of cells in G(1) phase after exposure to TNFalpha. When TNFalpha was added 12 h before RT, the surviving fraction at 2 Gy was 60% lower than that obtained with irradiation alone (0.29 vs 0.73, respectively, P0.00001). In combination treatment, cell cycle analysis demonstrated that TNFalpha reduced the number of cells in radiation-induced G(2) arrest, blocked irreversibly the cells in G(1) phase, and showed an additive decrease of the number of cells in S phase. In mice, RT as a single agent slowed tumour progression as compared with the control group (P0.00001). BAb+TNFalpha+RT combination enhanced the delay for the tumour to reach 1500 mm(3) as compared with RT alone or with RT+TNFalpha (P=0.0011). Median delays were 90, 93, and 142 days for RT alone, RT+TNFalpha, and RT+BAb+TNFalpha groups, respectively. These results suggest that TNFalpha in combination with BAb and RT may be beneficial for the treatment of pancreatic cancer in locally advanced or adjuvant settings.

Objectif de l’etude L’objectif etait l’etude retrospective visant a evaluer le controle local la survie globale, la survie sans progression et la toxicite. Des facteurs predictifs de reponse au traitement ont ete recherches. Materiel et methode Trente-cinq patients atteints de carcinome hepatocellulaire inoperables ont ete pris en charge entre mars 2013 et decembre 2016 par irradiation en conditions stereotaxiques dans notre centre. La radiotherapie en conditions stereotaxiques a ete realisee en respiration libre avec gating adaptatif sur un accelerateur TrueBeam Novalis par une technique d’arctherapie dynamique. Le controle local a ete evalue selon les criteres Modified Response Evaluation Criteria in Solid Tumors (mRECIST). Les donnees de survie ont ete analysees avec la methode Kaplan–Meier. Resultats Le suivi median etait de 10,7 mois. La dose mediane prescrite dans le volume cible previsionnel etait de 50 Gy en cinq fractions. Au regard des contraintes de dose aux organes a risque ou en cas d’alteration de la fonction hepatique, la dose et le fractionnement ont ete adaptes. La taille mediane des lesions etait de 37 mm (extremes : 10–100 mm). Soixante-neuf pour cent des patients avaient recu un pretraitement lourd : 43 % des patients avaient eu une chimioembolisation transarterielle (transarterial chemoembolisation [TACE]), 31 % une radiofrequence, 14 % avaient subi une resection chirurgicale, 11 % avaient recu du sorafenib. Quarante-trois pour cent des patients n’avaient pas eu de pose de reperes fiduciels. La probabilite de controle local etait de 100 % a 6 mois et 94 % a12 mois, celle de survie globale respectivement de 94 % et 80 %, celle de survie sans progression etait de 76 % et 30 %. Aucun facteur ne semblait predictif de la survie globale ni de la survie sans progression parmi les facteurs testes (valeur du volume cible previsionnel, fractionnements, pose de clip), probablement par manque de puissance. Il n’y a eu aucun cas d’hepatite radio-induite (radiation induced liver disease [RILD]), ni aucun deces iatrogenique. Un patient a souffert d’un ulcere gastroduodenal de grade 3. Conclusion Nos resultats sont concordants avec les donnees de la litterature et confirment que la radiotherapie en conditions stereotaxiques est une technique efficace et bien toleree. Neanmoins, des etudes prospectives randomisees permettraient d’evaluer sa place dans la strategie therapeutique.

Objectif de l’etude Evaluer le devenir a long terme de patients pris en charge pour un carcinome anal par radiotherapie conformationnelle avec modulation d’intensite (RCMI). Materiel et methode Entre aout 2007 et septembre 2015, 233 patients atteints d’un carcinome epidermoide du canal anal ont ete pris en chage par RCMI, notamment par arctherapie volumetrique depuis 2009. L’irradiation delivrait 45 Gy en 25 fractions d’1,8 Gy, cinq jours par semaine, a la tumeur initiale et aux aires ganglionnaires pelviennes et inguinales (premier volume cible previsionnel, PTV1). Un boost (non integre) de 14,4 a 20 Gy etait ensuite administre a la tumeur initiale (deuxieme volume cible previsionnel, PTV2), par fractions de 1,8-2 Gy ou par curietherapie. Les tumeurs localement evoluees recevaient une chimiotherapie concomitante par 5-fluoro-uracile-mitomycine ou 5-fluoro-uracile -cisplatine. La toxicite a ete etudiee avec l’echelle Common Terminology Criteria for Adverse Events, version 4.0. L’etude des 166 premiers patients est presentee ici. Resultats Les dossiers de 124 femmes (75 %) et 42 hommes (25 %) ont ete analyses. L’âge median etait 61 ans (36–92 ans). Les tumeurs etaient de stades I, II, III et IV chez respectivement 13 %, 25 %, 57 % et 4 % des patients. Treize etaient immunodeprimes, dont dix infectes par le virus de l’immunodeficience humaine (6 %), 132 (80 %) ont recu une chimioradiotherapie et 34 (20 %) une radiotherapie seule. Avec un suivi median de 46,7 mois (intervalle de confince a 95 % [IC95 %] : 41,2–51,6, aucune toxicite tardive de grade 4 n’a ete observee. Vingt patients (12 %) ont souffert d’une toxicite de grade 3, diarrhee, rectite, hematurie, radiodermite, incontinence anale et/ou stenose vaginale. Il n’y avait pas de toxicite hematologique tardive significative ( p = 0,23). Trente-six cancers (22 %) ont recidive, 24 locoregionalement (67 %), 12 a distance isolement (33 %). Trente-trois patients (20 %) ont ete colostomises apres la radiotherapie, dont 17 pour recidive locale et 12 pour toxicite radioinduite. Le taux de survie globale a 3 ans etait de 85,5 % (IC95 % : 78,7–90,3), celui sans recidive locoregionale de 86,9 % (IC95 % : 80,3–91,4), celui sans maladie de 74,6 % (IC95 % : 67,0–80,8) et celui sans colostomie de 81,2 % (IC95 % : 74,0–86,6). Conclusion La RCMI devient un traitement standard des cancers du canal anal. Une analyse dosimetrique completera ces resultats.

Objectif L’implantation de dispositifs intraprostatiques permettant de suivre la cible pendant toute l’irradiation est aujourd’hui possible (Calypso®, Varian Medical Systems). La diminution des marges du volume cible previsionnel pouvant alors etre envisagee, l’objectif de notre etude etait d’evaluer son apport dosimetrique. Materiels et methodes Les dossiers de dix patients precedemment qui ont recu arctherapie avec une technique de boost integre delivrant 80 Gy et 56 Gy en 40 fractions ont ete etudies. Nous avons compare la dosimetrie initialement planifiee avec les marges du protocole du Groupe d’etudes des tumeurs urogenitales (Getug) 06 a une nouvelle dosimetrie avec des marges reduites a 3 mm, sauf autour des vesicules seminales : 10 mm longitudinalement et lateralement, 5 mm en arriere et 3 mm en avant. La prescription initiale du deuxieme volume cible previsionnel recevant 95 % de la dose a ete poussee jusqu’a ce que le volume recevant 99,5 % de la dose (V99,5 %) soit egal au deuxieme volume cible previsionnel recevant 95 % de la dose pour le deuxieme volume cible previsionnel avec une marge de 3 mm et ce dernier a ete analyse dans le traitement initial pour comparaison. Resultats Les volumes cibles ont ete diminues de 50 % pour le deuxieme volume cible previsionnel (prostate) et 40 % pour le premier volume cible previsionnel (prostate et vesicules seminales). Les doses dans 99,5 % (D99,5) et 98 % (D98 %) du deuxieme volume cible previsionnel avec une marge de 3 mm etaient ameliorees avec le nouveau plan avec respectivement 76 Gy contre 74,8 Gy [73,8–77,2] et 77,9 Gy [77,3–78,7] contre 76,3 Gy [75,2–78,2]. La dose dans 2 % du volume (D2 %) augmentait de 3 % a 81,9 Gy [80,6–82,5] contre 84,8 Gy [83,4–87,2]. Une diminution de la dose etait observee dans 50 % (D50 %) du rectum de 53 % (12,8 Gy [8,41–7,6] contre 27 Gy [17,7–31,9]) et de 74 % dans le volume recevant 70 Gy (V70 Gy) (2,5 % [0–5,7] contre 9,5 % [4,7–12,7]). Le volume recevant 80 Gy (V80 Gy) etait compris entre 0 et 0,7 % avec les marges de 3 mm. Pour la vessie, la D50 % etait reduite de 41 % (11,8 Gy [2,7–18,8] contre 20,1 Gy [3–42,9]) et le V70 Gy de 80 % (2,7 % [0,2–4,6] contre 13,4 % [2,6–22,6]). Le V80 Gy etait identique a 0,6 %. Conclusion Une meilleure epargne dosimetrique aux organes critiques est clairement demontree grâce a la reduction des marges du volume cible previsionnel. Une etude de faisabilite de l’utilisation des dispositifs evoques ci-dessus confirmerait une diminution de la toxicite.

Radiation therapy is now widely accepted as an efficacious treatment of localized prostate cancer. The technical developments of recent years have enabled the evolution of a three-dimensional conformal radiotherapy, offering a better adaptation of the dose distribution, and leading therefore to preserve organs at risk. In addition, the required dose delivered to the target volume permit physician to increase the total dose if necessary. This requires a thorough knowledge of the radio-anatomy of the prostate, the natural history of the disease but also the ballistics and dosimetry. The objectives of this work were to detail epidemiology and radio-anatomy of the prostate cancer. In addition, conformal radiation modalities are illustrated by a case report.

Intensity-modulated radiotherapy (IMRT) has highly impacted on the dose delivery thanks to inverse-planning dosimetry. Conformal isodoses to target volumes and critical organ protection have led to treatment possibilities which were unrealizable with conventional 3D technique. Nevertheless, time delivery using IMRT was in some cases longer than 3D radiotherapy. In order to compensate for this limitation, we have developed since 2007 a volumetric modulated arctherapy (RapidArc) in partnership with Varian. The technique, the results of the dosimetry plans, and quality control of the 142 first patients treated since November 2008 are presented in this review.

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.

Purpose In this paper, we used the Intrafration Motion Review technique (IMR, Varian medical system), which allows simultaneous kV/MV utilization to analyse the liver motion during gated RapidArc stereotactic treatment. Materials and methods Eight liver cancer patients with implanted fiducial markers were treated using the gated RapidArc technique with a Varian Novalis Truebeam linear accelerator. Four 4D computed tomography (CT) scans were acquired using Real time Position Management (RPM) system to study the reproducibility of liver motion. The cine 4D CT images were separated into 10 phases CT series based on respiratory motion information. A Maximum Intensity Projection (MIP) and an Average Intensity Projection (Ave-IP) CT series were generated. The Internal Target Volume (ITV) was outlined in the MIP CT series. The Planning Target Volume (PTV) was created by adding a 5 mm margin from the ITV. The fiducials were marked in the exhalation and/or in the inhalation phase making possible the intrafraction verification. The treatment planning is realized in the Ave-IP CT series. The patient's alignment is set based on markers using daily cone beam CT (CBCT). During the treatment, kV images were acquired at each exhalation or inhalation phase when the respiratory signal cross the upper and lower gating threshold defined during the respiratory learning process. The positions of the fiducials markers were compared with their expected positions. Results The average (±SD) conformity index CIPTV = (VPTV95% (cc)/ VPTV (cc)) * (VPTV95% (cc)/ Viso95% (cc)) was 0.93 ± 0.02 and homogeneity index HIPTV = (D2% - D98%)/Dmedian was 0.09 ± 0.02. The average MU/Gy was 147 ± 25. The room occupation's time was 53, 30, 20, 24, 24 min respectively for the five first fractions. The average kV images acquired per fraction were 35 with a maximum of 74 images and a minimum of 12 images. The average gating errors of the fiducials in the Superior–Inferior (SI) direction during the intrafraction was 0,91 mm with a maximum of 6 mm. Conclusion For tumor motion, monitoring intra-fraction by IMR ensures with certainty the PTV irradiation estimates with a systematic checking of the position of the target volume (fiducials) when this one come inside the region of treatment.

To report our experience on treatment planning and acute toxicity in 16 patients suffering from clinically localized prostate cancer treated with high-dose intensity-modulated radiation therapy (IMRT).- Between March 2001 and October 2002, 16 patients with clinically localized prostate cancer were treated with IMRT. Treatment planning included an inverse-planning approach, and the desired beam intensity profiles were delivered by dynamic multileaf collimation. All patients received the entire treatment course with IMRT to a prescribed dose of 78 Gy. All IMRT treatment plans were compared with a theoretical conventional three-dimensional conformal radiation therapy (3D-CRT). Acute lower gastro-intestinal (GI) and genito-urinary (GU) toxicity was evaluated in all patients and graded according to the Common Toxicity Criteria for Adverse Events version 3.0 (CTCAE v. 3.0). A relationship between dose volume and clinical toxicity was evaluated.- Ninety-five percent of the PTV2 received more than 76 Gy using IMRT or 3D-CRT with no difference between both methods. The dose-volume histogram mean obtained for the PTV2 was not different between IMRT and 3D-CRT. IMRT improved homogeneity of the delivered dose to the PTV2 as compared with 3D-CRT (7.5 vs 9%, respectively). Ninety-five percent of the PTV1 received 5 Gy more using IMRT with protection of the bladder and the rectum walls. The benefit was considered below 75 and 70 Gy for the wall of the bladder and the rectum, respectively. Grade 2 GI and GU toxicity was observed in four (25%) and five (31%) patients, respectively. No grade 3 toxicity was observed. There was a trend towards a relationship between the mean rectal dose and acute rectal toxicity but without statistical significant difference (P =0.09).- Dose escalation with IMRT is feasible with no grade 3 or higher acute GI or GU toxicity. Examination of a larger cohort and longer-term follow-up are warranted in the future.

Objectifs Evaluer la precision d’un nouvel algorithme de reduction des artefacts metalliques (MAR, GEMS) sur la qualite de la reconstruction des tissus avoisinants une prothese metallique. Materiels et methodes Les images du fantome CIRS ED (15 inserts de differentes densites connues) ont ete acquises sur un scanographe GE Optima CT580 a 120 kV. Le cas A (reference) ne contenait pas d’insert metallique. Les cas B (insert titane 4,5 g/cm3), C (prothese en acier 8 g/cm3) et D (insert plomb 11,4 g/cm3) comprenaient un insert lateral unique. Le cas E simulait une prothese bilaterale (plomb). Les cinq cas ont ete reconstruits avec MAR et sans (NO MAR). Le nombre Hounsfield moyen (HUn) de chaque insert et l’ecart-type correspondant (σHUn) representant le bruit dans l’image ont ete releves et compares pour chaque cas a la reference (A) avec et sans MAR. Resultats Les resultats sont presentes dans le Tableau 1 . Conclusion Cette etude montre que l’algorithme MAR reduit les artefacts, ameliore le bruit et la precision des HU dans les images pour les tissus avoisinants des inserts metalliques. Pour les implants unilateraux, les meilleurs resultats ont ete obtenus avec la prothese en acier par rapport aux inserts en titane et en plomb. L’impact dosimetrique reste a evaluer.

blocks, which could open the way to improved CTV definition and planning. Materials/Methods: An in-house, spectral domain OCT system was developed for this study. A pair of tilting galvanometer mirrors permits lateral scanning of the infrared beam resulting in a 5x5x3-mm image volume. Paraffin blocks (40x25x4 mm) containing formalin-fixed mouse mammary glands with tumor were imaged. Other than removing the plastic mount, the blocks were not manipulated in any way in preparation for imaging. After each scan, the blockswere translated on amoveable stage until the entire samplewas imaged. Blocks were scanned through both sides in order to image their full thickness. Individual scans were stitched together to generate a final, complete image volume. For comparison, sections at multiple depths were obtained from the blocks, stained with hematoxylin and eosin (H&E), and photographed at high magnification and resolution. Results: Complete 3D images of the tissue blocks were obtained. The scan time for a single 5x5x3-mm image was about 15 seconds. A lateral resolution of 16 mm and a 6-mm resolution in the depth direction permitted visualization of tissue micro-architecture that correlated with the H&E section images. Images from consecutive blocks could be stitched together, allowing reconstruction of larger specimens over multiple blocks. Because of the paraffin medium, both micro-CT and small animal MRI were unable to visualize any features within the blocks. Conclusions: Optical coherence tomography is a fast, non-invasive, highresolution imaging modality capable of volumetric reconstruction of paraffin tissue blocks. As such, it could greatly facilitate the imaging and analysis of microscopic disease needed to study and improve CTV design and treatment. Author Disclosure: L. Kim: None. R. Droz-Rosario: None. E. Hwuang: None. L. Higgins: None. M. Pierce: None.