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Resume Objectif de l’etude L’objectif de cette etude etait d’evaluer l’efficacite et la tolerance d’un complement de dose de protons pour les patients atteints d’un cancer du nasopharynx localement evolue. Patients et methodes De novembre 1999 a septembre 2016, 17 patients atteints d’un cancer du nasopharynx de stade III–IVa ont ete pris en charge au centre de protontherapie d’Orsay de l’institut Curie. Les aires ganglionnaires cervicales bilaterales ont ete traitees par des photons a la dose de 40–54 Gy. La tumeur et ses extensions microscopiques ont recu une dose complementaire de protons pour atteindre la dose de 70–78 Gy. Tous les patients ont recu une chimiotherapie concomitante. Le controle local, la survie sans recidive et la survie globale ont ete determines, ainsi que la toxicite aigue et tardive. Resultats Les caracteristiques des patients etaient : un âge median de 49 ans, le sexe masculin pour 71 % des cas, 88 % des cancers etaient de stade IVa avec une majorite T4N0M0 (82 %). La mediane de suivi etait de 99 mois. Les probabilites de controle local et de survie globale actuarielle ont ete respectivement 94 % et 88 % a 2 ans, 86 % et 74 % a 5 ans, 86 % et 66 % a 10 ans. La toxicite tardive de grade ≥ 3 a ete la perte auditive (23,5 %) et une osteo-radio-necrose de l’os sphenoide (5,9 %). Conclusion Le complement de dose de protons semble donc une bonne alternative pour le traitement des cancers du nasopharynx localement evolues, en particulier pour ceux de stade T4N0M0.

Goals Prospective evaluation of salivary gland preservation, overall survival and local recurrence-free survival after head and neck cancer treated by helical tomotherapy (HT). Material and methods From March 2007 to February 2009, 30 patients with head and neck cancer were treated by HT. The salivary excretion fraction (SEF) was assessed by technetium salivary gland scintigraphy before, and 6, 12 and 18 months after HT to define salivary gland preservation rates. Patients were reviewed every 3 months to assess clinical toxicity. Results The median follow-up was 4.3 years. The mean dose to the ipsilateral parotid gland (IPG) was 25.4 Gy. Good preservation of parotid gland function was observed in 84% of the 19 patients evaluated by scintigraphy at 18 months. The 5-year local recurrence-free survival (LRFS) was 100% among the 6 patients who received a dose of more than 26 Gy to the parotid gland. The 28-month LRFS was 33% in the group that received a dose of less than 20 Gy versus 91% in the group that received a dose of more than 20 Gy to the IPG. Conclusions Helical tomotherapy reduced the incidence and severity of xerostomia. A mean dose to the parotid between 20 and 26 Gy allowed preservation of salivary function without compromising treatment efficacy. However, parotid-sparing HT requiring a mean dose less than 20 Gy is associated with an increased risk of recurrence.

Resume Buts Evaluation prospective de la preservation des glandes salivaires, des survies globales et sans recidive locale apres traitement de cancers ORL par tomotherapie helicoidale (TH). Materiel et methodes De mars 2007 a fevrier 2009, 30 patients atteints de cancers ORL ont ete traites par TH. La fraction d’excretion salivaire (FES) a ete evaluee par scintigraphie au technetium avant, 6, 12 et 18 mois apres la TH, permettant de definir le taux de preservation glandulaire. Parallelement, les patients ont ete examines tous les 3 mois pour evaluer les toxicites cliniques. Resultats Le suivi median a ete de 4,3 ans. La dose moyenne recue aux glandes parotides homolaterales (GPH) a ete de 25,4 Gy. Dix-neuf patients ont pu etre evalues a 18 mois par scintigraphie, et ils ont eu une bonne preservation des GP (84 %). Parmi les 6 patients ayant recu plus de 26 Gy dans la parotide, la survie sans recidive locale (SSRL) etait de 100 % a 5 ans. La SSRL a 28 mois etait de 33 % dans le groupe ayant recu moins de 20 Gy versus 91 % dans le groupe ayant recu plus de 20 Gy a la GPH. Conclusions La tomotherapie helicoidale nous a permis de reduire l’incidence et la severite de la xerostomie. Nous avons montre qu’une dose moyenne delivree aux parotides entre 20 et 26 Gy preservait la fonction salivaire sans compromettre l’efficacite du traitement. Par contre, la preservation parotidienne limitant la dose moyenne en dessous de 20 Gy augmente le risque de recidive locale.

The aim of this study was to assess the treatment outcome and toxicity for patients with locally advanced nasopharyngeal carcinoma treated with a complementary dose with proton.Between November 1999 and September 2016, 17 patients have been treated for a stage III-IVa nasopharyngeal carcinoma in the proton therapy centre of Curie Institute. Bilateral lymph node in the neck (I-V levels) received from 40 to 54Gy with photon beam. The primary tumor volume including microscopically extensions received a complementary dose with proton in order to reach the dose of 70 to 78Gy. All the patients received a concomitant chemotherapy. The end-points of the study were loco-regional control, survival, and treatment-related toxicity.Patients characteristics were: median age 49, 71 % male, 88% stage IVa, with a majority (82%) of T4N0M0. The median follow-up was 99 months. The 2-, 5- and 10-year actuarial locoregional free survival and overall survival were 94% and 88%, 86% and 74%, and 86% and 66%, respectively. The grade≥3 late adverse events were sphenoid bone radionecrosis (5.9%) and hearing loss (23.5%).This study showed that a complementary dose with proton seems to be a good option for the treatment of locally advanced nasopharyngeal carcinoma, particularly for T4N0M0.

Purpose We report the patient outcomes of a treatment combining proton therapy and Tomotherapy in sinonasal adenoid cystic carcinoma involving skull base. Materials and methods We included patients treated at Curie Institute, Paris, France, between March 2010 and February 2014 for an advanced adenoid cystic carcinoma involving skull base. Patients received Tomotherapy, proton therapy or both. We evaluated treatment toxicity (according to CTCAE V4), local control, distant metastasis-free survival and overall survival. Results Thirteen patients were included, with a median follow-up of 34 months. Radiation therapy followed surgery for 77% of the patients and margins were positive in all those cases. Median dose was 73.8 Gy. Local control, distant metastasis-free survival and overall survival at 3 years were respectively 60%, 48% and 60%. One-sided grade 3 hearing impairment occurred in 46% of the patients. Conclusion Combining high-dose proton therapy and Tomotherapy is effective and has moderate toxicity in the treatment of T4 sinonasal adenoid cystic carcinoma involving skull base.

Resume Objectif Evaluer la tomotherapie helicoidale du mesotheliome pleural malin et l’impact des faibles doses sur la toxicite pulmonaire et œsophagienne. Patients et methodes De juin 2007 a mai 2011, 29 patients atteints de mesotheliome pleural malin ont recu une la tomotherapie helicoidale adjuvante. L’âge median etait de 63 ans (34–72). Histologiquement, 83 % des patients etaient atteints d’un mesotheliome pleural malin epithelioide. Cliniquement, 45 % des tumeurs etaient classees T3 et 55 % N0. Quatre-vingt-six pour cent des patients ont ete operes par pleuropneumonectomie extrapleurale et 35 % ont recu une chimiotherapie neoadjuvante par sels de platine et pemetrexed. La dose mediane dans la cavite de pneumonectomie etait de 50 Gy en 25 fractions de 2 Gy. Resultats Le suivi moyen etait de 2,3 ans apres le diagnostic. Les probabilites de survie globale etaient respectivement de 65 et 36 % a un et deux ans. La duree mediane de survie a partir du diagnostic etait de 18 mois. Les volumes pulmonaires medians recevant 2, 5, 10, 13, 15 et 20 Gy (V2, V5, V10, V13, V15 et V20) etaient respectivement de 100, 98, 52, 36, 19 et 5 %. La mediane de la dose moyenne au poumon restant etait de 11 Gy. Deux patients sont decedes de complications pulmonaires, trois ont souffert d’une pneumopathie de grade 3, tandis qu’une toxicite œsophagienne de grade 3–4 a ete observee chez trois. Aucun impact significatif des caracteristiques cliniques et des parametres dosimetriques releves n’a ete retrouve sur la toxicite pulmonaire, cependant un V10 de 50 % ou plus, un V15 de15 % et ou plus une dose moyenne au poumon restant de 10 Gy ou plus auraient une tendance a etre predictifs de toxicite pulmonaire ( p p = 0,03), ainsi que les faibles doses pulmonaires : V5, V10 et V13 ( p Conclusion La tomotherapie helicoidale est une technique prometteuse dans la prise en charge multimodale des mesotheliomes pleuraux malins. Les faibles doses recues par le poumon controlateral semblent etre cependant le facteur limitant. Il serait interessant de les comparer a celles delivrees par d’autres techniques comme l’arctherapie volumetrique modulee.

The majority of patients who develop liver metastases in metastatic colorectal cancer (mCRC) has often unresectable disease. Several new methods of nonsurgical ablation have been tested with variable success. Helical tomotherapy (HT), such as intensity-modulated radiation therapy (IMRT) or stereotactic body radiotherapy therapy, is a recent radiation therapy technique which can provide simultaneous and precise targeting of multiple lesions, while sparing normal tissues. We retrospectively assess the feasibility and the tolerance of IMRT with capecitabine followed by hepatic surgery in mCRC patients. This original observation suggests that HT could be safely integrated in the multidisciplinary management of patients with metastatic colorectal cancer as an alternative to surgery or other local ablation therapies.

Resume Introduction Malgre son interet theorique, peu de donnees concernent le traitement du mesotheliome pleural malin (MPM) par la tomotherapie helicoidale (TH). Patients et methodes Quatorze patients atteints de MPM ont recu un traitement adjuvant par TH a l’institut Curie et au centre Rene-Gauducheau depuis le 1/08/2007. Tous les patients ont eu une pleuro-pneumonectomie extrapleurale (PPEP). La dose mediane dans la cavite de pneumonectomie etait de 50 Gy (48–54 Gy) tandis que les zones a haut risque ont recu concomitamment 57 Gy (54–69 Gy). Resultats Le suivi median etait de 12,6 mois apres la TH. Sept patients ont recu une chimiotherapie neoadjuvante par platine et pemetrexed. Huit patients etaient T3 et cinq patients etaient N1-2. La TH a ete majoritairement bien toleree. Deux patients suspects de pneumopathie radique sont neanmoins decedes. Parmi les 12 patients ayant survecus, six ont recidive : deux recidives locales et metastatiques, quatre metastatiques uniquement. Trois patients sont decedes de leur recidive. La survie mediane a partir du diagnostic etait de 18,4 mois. Une courbe d’apprentissage a ete observee dans l’optimisation des parametres dosimetriques. Conclusion La TH est une technique fiable, plutot bien toleree et efficace, pour traiter les patients atteints de MPM apres PPEP.

To evaluate the dosimetry of helical tomotherapy (HT) and three-dimensional conformal radiotherapy (3D-CRT) in breast cancer patients undergoing whole breast radiation with simultaneous integrated boost (SIB) of the tumor bed.Thirteen patients with breast cancer treated by lumpectomy and requiring whole breast radiotherapy with tumor bed boost were planned using both HT and 3D-CRT using the field-in-field technique. The whole breast and tumor bed were prescribed 50.68 Gy and 64.4 Gy, respectively, in 28 fractions. Dosimetries for both techniques were compared.Coverage of the whole breast was adequate with both techniques (V(95%)=96.22% vs. 96.25%, with HT and 3D-CRT, respectively; p=0.64). Adequate tumor bed coverage was also achieved, although it was significantly lower with HT (V(95%)=97.18% vs. 99.72%; p0.001). Overdose of the breast volume outside the tumor bed was significantly lower with HT (V(54.23 Gy)=12.47% vs. 30.83%; p0.001). Ipsilateral lung V(20 Gy) (6.34% vs. 10.17%; p0.001), V(5 Gy) (16.54% vs. 18.53%; p0.05) and mean dose (4.05 Gy vs. 6.36 Gy; p0.001) were significantly lower with HT. In patients with left-sided tumors, heart V(30 Gy) (0.03% vs. 1.14%; p0.05) and mean dose (1.35 Gy vs. 2.22 Gy; p0.01) were significantly lower with HT, but not V(5 Gy). Contralateral breast V(5 Gy) (0.27% vs. 0.00%; p0.01) and maximum dose were significantly increased with HT.In breast cancer treated with SIB, both HT and 3D-CRT provided adequate target volume coverage and low heart doses. Tumor bed coverage was slightly lower with HT, but HT avoided unnecessary breast overdosage while improving ipsilateral lung dosimetry.

For treatments with dynamic intensity modulated radiotherapy (IMRT), the adjustment of multileaf collimator (MLC) parameters affecting both the optimization algorithm and dose distributions is crucial. The main parameters characterizing the MLC are the transmission (T) and the dosimetric leaf separation (DLS). The aim of this study is twofold: a methodology based on the 'sliding slit' test is proposed to determine (T, DLS) combinations inducing the best conformity between calculations and measurements. Secondly, the effects of the MLC adjustment on measured dose and on optimization are presented for different configurations as the chair test and for the patient dosimetric quality control (DQC). Tests were performed with a Varian 23EX linac operated at 20 MV and equipped with a 120 leaf Millenium dynamic collimator. The treatment planning system was CadPlan/Helios (version 6.3.6). Results demonstrated that the sliding width (SW) strongly depends on the (T, DLS) combinations, and the measured dose is a linear function of the SW. Different (T, DLS) combinations induced a good agreement between calculations and measurements. The influence of the MLC calibration was found to be particularly important on the 'sliding slit' test (11.8% for a gap change of 0.8 mm) but not so much on the chair test and on the DQC. To detect small variations in leaf adjustment and to ensure consistency between calculation and actual dose delivered to patients, a daily check called IMRT MU check is proposed.

Resume Objectif de l’etude. – La radiotherapie conformationnelle avec modulation d’intensite (RCMI) repose sur une methodologie dite de planification inverse ou, a partir d’objectifs dosimetriques, des contraintes d’optimisation sont introduites dans le logiciel de planification inverse qui calcule la modulation d’intensite a appliquer a chacun des faisceaux pour obtenir la distribution de dose souhaitee. Selon la maniere dont cette modulation est appliquee et en fonction des contraintes fixees et des performances du logiciel utilise, les resultats de l’optimisation peuvent etre differents de ceux attendus. On est alors amene a rechercher les contraintes d’optimisation qui permettent de satisfaire les objectifs dosimetriques. L’objectif de ce travail etait de presenter la demarche adoptee a l’institut Curie pour passer progressivement de la technique conformationnelle tridimensionnelle a la RCMI. Patients et methodes. – L’etude a porte sur les 12 premiers patients traites avec modulation d’intensite a partir de juin 2002. Les traitements ont ete effectues avec un appareil Varian Clinac 23EX et la planification sur le logiciel Varian CadPlan–Helios. Nous avons en particulier analyse les criteres et les contraintes utilises et evalue le benefice apporte par la modulation d’intensite en termes de couverture du volume cible (indice de conformite) et de protection des organes critiques. Dans tous les cas, une partie du traitement a ete effectuee sans et le reste avec modulation d’intensite. Resultats et conclusion. – Les resultats ont confirme que, pour obtenir une amelioration de la protection des organes a risque sans degrader l’homogeneite de la dose delivree au volume cible, il y avait interet a effectuer la plus grande partie du traitement avec modulation d’intensite. Pour nous rapprocher des objectifs dosimetriques fixes, nous avons du utiliser des contraintes plus strictes qui ont pu etre conservees pour tous les patients a l’exception des contraintes dose–volume sur le rectum. Le facteur de conformation a ete ameliore de 16 % pour les traitements avec modulation d’intensite. En etudiant la possibilite d’effectuer un traitement complet avec modulation d’intensite, nous avons constate qu’en faisant deux plans de traitement successifs en considerant la prostate et vesicules seminales d’une part et la prostate seule d’autre part, des resultats optimaux ont ete obtenus. De tres bons resultats ont ete egalement obtenus en definissant de nouveaux jeux de contraintes sur deux volumes cibles previsionnels distincts associes respectivement a la prostate seule et aux vesicules seminales seules. Cette maniere de faire correspond a notre pratique actuelle.

Head and neck tumors represent very interesting targets for IMRT techniques because of the complex shape of the structures and the organs at risk close by. The use of this kind of techniques requires a quality assurance protocol. The physicists of the GORTEC group shared their experience to define some recommendations in order to draw up a QA protocol. The dosimetric verification of the treatment plans (in terms of absolute and relative dose), the control of the reproducibility of the patient positioning and the use of a record and verify system to control the different parameters form the main parts of these recommendations. Each chapter comprises a description of the different methods, recommendations concerning the equipment, the adopted tolerances, the frequency of controls. At the end of each chapter, a table summarizes the main actions to carry out. These recommendations will allow to harmonize our practices whatever the softwares and the accelerator that are being used. They will simplify the task of the teams that wish to implement IMRT for head and neck tumors.

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

The skeleton is the first and most common site of distant metastases in breast cancer patients. Tumor bone disease is responsible for a considerable morbidity and markedly decreases the quality of life of patients [1]. Although providing rapid and lasting pain relief in symptomatic bone metastases, external beam radiotherapy may be associated with treatment-induced morbidity, particularly in patients with multiple skull metastases. For those patients, conventional radiotherapy may be deleterious, delivering high radiation doses to critical organs such as eyes or brain and leading to potential subsequent progressive neurocognitive decline. Helical tomotherapy (HT) combines intensity modulated fan-beam radiotherapy with megavoltage computed tomography imaging for patient positioning [2]. Its availability has recently opened new fields of exploration for palliative radiotherapy due to its ability to tailor very sharp dose distributions around the target volumes. Here, we report an interesting case of palliative use of HT in a breast cancer patient with multiple skull bone metastases. In October 2007, a 76-year-old patient presented with acute left peripheral facial paralysis and inflammatory bone pain occurring at the left part of her face. She had a previous history of invasive ductal carcinoma with multiple bone metastases. The CT scan and the bone scintigraphy showed multiple lytic bone metastases of the skull, predominant in the fronto-temporo-parietal area, extending to the chin, as shown in Fig. 1a and d, respectively. The patient was referred for HT, delivering 20 Gy using 6 MV photons, at 4 Gy per daily fraction, total duration 5 days, in the planning target volume (PTV), concurrently with highdose corticoids. The patient was treated lying on her back. A customized mask was used for immobilization and patient positioning. The mean doses delivered to 20%, 40%, and 100% of the left eye were 7.5, 5, and 2.5 Gy, respectively. The mean doses delivered to 20%, 40%, and 100% of the right eye were 2.5, 2, and 1 Gy, respectively. The mean doses delivered to 20%, 40%, and 100% of the brain were 10, 6, and 2.5 Gy, respectively. No acute toxicity was observed.

Resume En radiotherapie externe la modulation d'intensite permet d'une part de compenser les variations d'epaisseur et l'influence des heterogeneites, et d'autre part, lors de l'association de plusieurs faisceaux, d'obtenir une distribution de dose precisement adaptee a la forme du volume cible. Les collimateurs multilames offrent la possibilite de realiser cette modulation d'intensite en jouant sur la position des lames en fonction du temps. Cette methode, rendue possible par les developpements de la technologie des accelerateurs et de l'informatique, presente plusieurs avantages par rapport a d'autres, tels que les filtres compensateurs. Nous avons mis au point un logiciel permettant le calcul de la relation entre position de lames et nombre d'unites moniteur pour obtenir une distribution d'intensite donnee, et l'avons applique a un accelerateur Varian, equipe d'un collimateur comportant 40 paires de lames. L'analyse des resultats experimentaux demontre la faisabilite et le potentiel de la methode.

To evaluate the adjuvant treatment of malignant pleural mesothelioma by helical tomotherapy and the impact of low doses on esophageal and pulmonary toxicity.Between June 2007 and May 2011, 29 patients diagnosed with malignant pleural mesothelioma received adjuvant radiotherapy by helical tomotherapy. The median age was 63 years (34-72). Histologically, 83 % of patients had epithelioid malignant pleural mesothelioma. Clinically, 45 % of patients were T3 and 55 % N0. Eighty six percent of the patients were treated by extrapleural pneumonectomy and 35 % received neoadjuvant chemotherapy with platinum and pemetrexed. The median dose in the pneumonectomy cavity was 50Gy at 2Gy/fraction.The mean follow-up was 2.3 years after diagnosis. Overall survival at 1 and 2 years was 65 and 36 % respectively. The median survival from diagnosis was 18 months. Median lung volumes receiving 2, 5, 10, 13, 15 and 20Gy (V2, V5, V10, V13, V15 and V20) were 100, 98, 52, 36, 19 and 5 %. The median of the mean remaining lung dose was 11Gy. Two patients died of pulmonary complications, three patients had grade 3 lung toxicity, while esophageal grade 3-4 toxicity was observed in three other patients. No significant impact of clinical characteristics and dosimetric parameters were found on pulmonary toxicity, however a V10≥50 %, a V15≥15 % and mean lung dose of 10Gy or more had a tendency to be predictive of pulmonary toxicity (P0.1). Moreover, in our analysis, the mean lung dose seems to have a significant impact on esophageal toxicity (P=0.03) as well as low doses to the controlateral lung: V5, V10 and V13 (P0.05).Helical tomotherapy is a promising technique in the multimodality treatment of malignant pleural mesothelioma. Low doses received by the contralateral lung appear to be the limiting factor. A dosimetric comparison with volumetric modulated arctherapy techniques would be interesting in this setting.

Purpose The purpose of this study is to implement dosimetric data libraries in a dose calculation algorithm Acuros XB (developed by Varian) in a treatment planning system, to validate the libraries and evaluate the performances of the algorithm with several tests in order to be used in the radiotherapy department. Materials and Methods Acuros XB (AXB) is implanted in the Eclipse TPS Version 10. The methodology used is that of the ESTRO booklet n°7 for the calculation of dose and monitor units (MU) with several levels of tests (level 1, 2 and 3 for static techniques, non-IMRT photon beams and one test with RapidArc technique). Level 1 tests assess AXB in simple configurations (square, rectangular fields) in absolute and relative dose, level 2 tests verify the accuracy consideration of beams modifiers (wedge filters, asymmetric fields), Level 3 tests, using the quality index methodology assess the modeling of the dose distribution with heterogeneity and scatter dose (small complex fields, thin central block) for 6 and 15 MV. Finally a test assesses AXB performances in a complex configuration (small fields, variation of dose rate, MLC movement) with the RapidArc technique. Dose calculations made by AXB on the Eclipse TPS are comparing to measurements which are the references in the same conditions. The tolerances fixed are those presented in the reports of the ESTRO 7 (static techniques, non-IMRT) and ESTRO 9 (IMRT and RapidArc). Main Results and Discussion The calculations made by AXB are in agreement with the measurements for all tests level. Some differences are observed, their number is nevertheless low. Differences between the calculations and measurements are observed at the interface water–air interface; however, they are less important than those observed in AAA and PBC. Conclusion and Discussion Acuros XB models and calculates accurately the dose in simple configurations, with modifiers beams, and with the presence of heterogeneities for static irradiation techniques, and also with a more complex configuration with the RapidArc technique. Acuros XB can be used as a dose calculation algorithm in the Eclipse TPS at the radiotherapy department of the Institut Curie Paris.

Objectif de l’etude Evaluer les techniques d’irradiation et leur toxicite dans les traitements des lymphomes hodgkinien et non hodgkinien avec atteinte mediatisnale durant une periode de 10 ans Materiel et methode Entre 2003 et 2015, 173 patients traites pour un lymphome de stade I a III ont ete traite dans le centre. Certains de ces patients ont ete pris en charge pour une atteinte mediatisnale, soit par irradiation conformationelle tridimensionnelle soit par RCMI. Resultats Vingt-six hommes et 43 femmes ont ete inclus dans cette etude. Le suivi median etait de 43 mois. Quarante-neuf patients ont ete pris en charge par irradiation conformationelle tridimensionnelle et 20 par RCMI. La dose mediane recue lors d’une irradiation d’un lymphome non hodgkinien etait de 40 Gy (36–44). La dose mediane recue lors d’une irradiation d’un lymphome hodgkinien etait de 30 Gy (30–36). Entre 2003 et 2006, 16 patients ont ete pris en charge par irradiation conformationelle tridimensionnelle et aucun par RCMI. Entre 2007 et 2009, 16 patients ont pris en charge par irradiation conformationelle tridimensionnelle et un par RCMI. Entre 2010 et 2015, 19 patients pris en charge par RCMI et aucun par irradiation conformationelle tridimensionnelle. Onze des 20 (55 %) patients pris en charge par RCMI et 35 des 49 (71 %) traites par pris en charge par irradiation conformationelle tridimensionnelle ont souffert d’au moins un symptome de toxicite aigue. Parmi les patients traites par irradiation conformationelle tridimensionnelle, un patient a ete atteint d’une pneumopathie grade 1 sequellaire. Aucun patient pris en charge par RCMI n’a souffert de toxicite tardive. Conclusion L’amelioration des techniques d’irradiation des lymphomes hodgkinien et non hodgkinien semble diminuer la toxicite aigue et tardive. Un suivi plus long est necessaire pour mieux evaluer la toxicite tardive.

La nanotechnologie offre un large eventail d’applications en medecine a la fois pour le diagnostic et le traitement. En therapie, les nanoparticules peuvent etre utilisees comme radiosensibilisateurs afin d’ameliorer les effets de la radiotherapie chez des patients atteints d’un cancer evolue localement. La base de radiosensibilisation repose principalement sur l’augmentation de l’absorption du rayonnement par le tissu tumoral injecte de nanoparticules par rapport au tissu non injecte grâce au haut numero atomique (Z > 60) des nanoparticules. Des elements tels que l’or, le gadolinium, le platine, l’hafnium sont preferes en tant que radiosensibilisateurs. Notre presentation portera sur la prise en charge des patients aux postes de traitement de radiotherapie inclus dans un essai therapeutique NBTXR3-301. La particule utilisee est l’oxyde d’hafnium, nomme NBTXR3. L’essai consiste a comparer les resultats de l’irradiation des patients injectes en intra-tumoral d’une preparation de nanoparticules d’hafnium avec ceux non injectes. L’etude concerne les patients ayant un sarcome des membres. Tous les patients sont operes apres une irradiation a la dose de 50 Gy. Une etude histopathologique est effectuee pour comparer la reponse a la radiotherapie avec et sans nanoparticule. L’irradiation tumorale est effectuee par radiotherapie avec modulation d’intensite. Les systemes d’immobilisation et l’imagerie de verification du positionnement des patients ainsi que la methode sont presentes de meme les particularites liees a ce type de patients seront commentes. Un protocole de mise en place des patients a ete defini decrivant le role du manipulateur pour ce type de traitement.

Background Helical tomotherapy (HT) is a relatively new method of radiotherapy, the main advantages of which are an increase of irradiation dose on the target tumour volume and best protection of adjacent organs at risk. Objective To provide an accurate evaluation of efficiency and tolerance of HT on different kinds of non-melanoma skin tumours. Patients and methods We analysed, retrospectively, 25 patients (pts) who were treated with HT for advanced non-melanoma skin cancers. We studied the characteristics of patients and tumours, associated treatments, characteristics, efficacy and tolerance of HT treatment. Results Eight had basal cell carcinoma, Eight had cutaneous squamous cell carcinoma, five Merkel cell carcinoma and four adnexal carcinoma. The median age was 75 years (range 51–89). The median follow-up was 12 months. HT was used because of incomplete excision (n = 12), lymph node involvement (n = 6), non-operable lesions (n = 4) and high risk of relapse (n = 4). The delivered dose for the tumour bed was between 50 and 70 Gy and for the lymph node it was between 50 and 64 Gy. There was no grade III–IV adverse event, except one grade III mucositis. Fourteen pts suffered from limited toxic effects 6 months after the end of the treatment, mainly loss of eyebrow and teared eye. Complete remission was noticed for 22 pts (88%); one pt had progressive disease and two pts died. Conclusion HT is an effective option for advanced non-melanoma skin cancers as radical treatment or in association with surgery. Early and late toxicity and cosmetic results are acceptable.

Although radiosensitive, spinal locations of Ewing's sarcomas are challenging for the radiation oncologist due to poor radiation tolerance of the spinal cord. However, some favorable anatomical compartments - that may represent more than 20% - were associated with a better outcome and could benefit from a radiation dose escalation using the most recent radiation therapy techniques.We performed a dose escalation study on one patient, declined in two scenarios: (1) a tumour located within a single vertebral body and (2) a locally advanced disease involving the vertebral foramen and paraspinal soft tissues. Five dose-levels are proposed: 44.8Gy, 54.4Gy, 59.2Gy, 65.6Gy and 70.4Gy (1.6Gy per session, 8Gy per week). The 3D-conformational technique is compared with static intensity modulated radiation therapy (IMRT), helical tomotherapy, volumetric modulated arc therapy (VMAT), stereotactic body robotic radiation therapy (SBRT) and protontherapy (passive scattering). Two constraints had to be respected in order to skip to the next level: the planned target volume (PTV) coverage must exceed 95% and the D(2%) on the spinal cord shall not exceed a given constraint set at 50Gy in case 1 and 44Gy in case 2 due to initial neurological sufferance.Only protontherapy, SBRT, helical tomotherapy and VMAT appear able to reach the last dose level while respecting the constraints in case 1. On the other hand, only helical tomotherapy seems capable of reaching 59.2Gy on the PTV in case 2.With the most recent radiation therapy techniques, it becomes possible to deliver up to 70.4Gy in a favorable compartment in this sham patient. Unfavorable compartments can receive up to 59.2Gy. Definitive radiation therapy may be an interesting local treatment option to be validated in an early phase trial.

Purpose: According to preliminary clinical experience, craniospinal irradiation (CSI) may be considered as a treatment option in patients with recurrent leukemia involving the central nervous system (CNS). Field matching poses challenges as it leads to a risk of underdosage or overdosage in the junctional area. We investigated the feasibility of CSI using helical tomotherapy (HT). Patients and methods: Four patients presenting with CNS recurrences of leukemia were referred to our department for salvage radiation therapy. Treatment planning was conducted by the EclipseTM system for 3D-CRT and IMRT, and with the Tomotherapy ® software for HT. Acute adverse events were monitored weekly using the Common Terminology Criteria for Adverse Events v 4.0. Results: Using HT, highly conformal irradiation could be delivered to CNS. Average doses to the encephalon were 25.1 Gy, 15.5 Gy, and 23.3 Gy using 3D-CRT, IMRT, and HT respectively. Spinal cord received an average dose of 18.9 Gy with 3D-CRT, 15.7 Gy with IMRT and 23.4 Gy with HT. Areas of overdosage to the brain or the spinal cord were also significantly decreased with HT. With HT, average doses to critical organs were also significantly decreased. No acute toxicity was reported with HT, whereas the patients treated by 3D-CRT and IMRT presented with grade II vomiting and asthenia. Conclusion: HT may optimize CSI in the treatment of CNS hematological recurrences by homogenously covering target volumes and improve clinical acute tolerance by more effectively sparing critical organs for preserving the quality of life. Further prospective assessments are warranted.

Helical tomotherapy is an innovative device combining with the same linac on board-imaging and IMRT facilities. The first national French evaluations, supported by National Institut of Cancer (INCa) are presented. Dosimetric characteristics as quality of homogeneity, cut-off outside target volumes allow IMRT treatments for large and complex volumes and a good organ at risk sparing. First comparative dosimetric studies are discussed.

There is little clinical data about the place of helicoidal tomotherapy (HT) in the treatment of malignant pleural mesothelioma (MPM). This new form of intensity modulated radiotherapy (IMRT) has great theoretical advantages in large and complex volumes when compared to "traditional" forms of radiotherapy.Fourteen patients diagnosed with MPM received adjuvant radiotherapy by HT. The patients were treated at the Curie Institute and the René Gauducheau Centre, starting in August 12007. All patients had a complete initial staging, an extrapleural pneumonectomy (EPP), and a minimum follow-up of six months. The median dose prescribed to the surgical cavity was 50 Gy (48-54 Gy) in 2 Gy (1.80-2.07) fractions. High dose regions received concomitant 57 Gy (54-69 Gy) in 2.16 Gy (2.00-2.30 Gy) fractions.Median follow-up was 12.6 months after ending HT. Seven patients received neoadjuvant chemotherapy (cisplatin or carboplatin, and pemetrexed). Eight patients were staged pT3 and five were staged pN1-2. HT was well tolerated. Two patients had suspected G5 radiation pneumonitis within 6 months of ending HT. Of the 12 patients who survived treatment, six relapsed (in average 5.1 months after HT): distant. Four relapses were distant; two relapses were both local and distant. Three patients died after their initial relapse. After initial diagnosis, the median survival was 18.4 months. A learning curve was observed in the optimization of the dosimetric parameters.Helicoidal tomotherapy is a reliable, quite well tolerated, and efficient way of treating MPM patients after an EPP.

After a request for proposal initiated by National Institute against cancer (INCa) in 2005, three French centers in France started tomotherapy in the first semester of 2007. A national policy of evaluation was performed to study the feasibility of this innovative technique and to compare the interest of helicoidal tomotherapy with other modalities of conformal therapy. Common protocols have been designed to facilitate this evaluation. Description of dose, IMRT levels and constraints are achieved according to each selected indication as: sarcoma, head and neck tumors, lung cancer, mesothelioma, bone metastases, anal carcinoma and craniospinal irradiation.

Head and neck tumors represent very interesting targets for IMRT techniques because of the complex shape of the structures and the organs at risk close by. The use of this kind of techniques requires a quality assurance protocol. The physicists of the GORTEC group shared their experience to define some recommendations in order to draw up a QA protocol. The dosimetric verification of the treatment plans (in terms of absolute and relative dose), the control of the reproducibility of the patient positioning and the use of a record and verify system to control the different parameters form the main parts of these recommendations. Each chapter comprises a description of the different methods, recommendations concerning the equipment, the adopted tolerances, the frequency of controls. At the end of each chapter, a table summarizes the main actions to carry out. These recommendations will allow to harmonize our practices whatever the softwares and the accelerator that are being used. They will simplify the task of the teams that wish to implement IMRT for head and neck tumors.

Intensity modulated radiation therapy (IMRT) is based on a methodology called inverse planning. Starting from dosimetric objectives, constraints of optimization are fixed and given to the inverse planning system, which in turn calculates the modulated intensity to apply to each beam. Since the algorithms allow the constraints to be violated, the results of optimization may differ from the initial dosimetric objectives. Consequently, the user is compelled to adapt the choice of the constraints according to the type of modulation and until satisfactory results are found. The purpose of this work is to present our experience in the choice of these constraints for prostate cancer treatments, as we moved from conformal radiotherapy to IMRT. Treatments were performed with a Varian 23EX linac and calculations were realized with the Varian CadPlan-Helios planning system.The approach used for the first 12 patients treated at institut Curie with IMRT from June 2002 was analysed. The treatment always consisted of a combination of conformal radiotherapy with and without intensity modulation.Results showed that, a larger fraction of the treatment performed with IMRT induced a better sparing of the organs at risk for the same homogeneous dose distribution to the target volume. Apart from the dose-volume constraint for the rectum, a fixed set of constraints, slightly more restrictive than the dosimetric objectives, could be used for all patients. Compared with conformal radiotherapy, the conformation factor for IMRT increased up to 16%. A specific study was undertaken in view of treatments completely performed with IMRT. The optimal technique consisted in performing separated IMRT plans for the two target volumes, the prostate volume and the prostate plus seminal vesicles volume respectively. Another satisfactory possibility was to define new constraints on two separated planning target volumes, prostate and seminal vesicles. This last approach is now routinely implemented for our IMRT patients.

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

Purpose: To provide an accurate evaluation of efficiency and tolerance (early and late cosmetic results) of HT on different kinds of non-melanoma skin tumours: basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (CSC), Merkel cell carcinoma (MCC) and adnexal carcinoma (AC). Patients and Methods: We analysed, retrospectively, all patients (pts) who were treated with HT for advanced stage skin cancers (including BCC, CSC, MCC and AC) between 2007 and 2010. We studied: Characteristics of the patients Characteristics of HT treatment Characteristics of the tumour Efficiency (follow-up duration, recurrence, remission, death) Associated treatments Tolerance of the treatment (early and late cosmetic results) Results: We included 24 patients (9 women (37.5%) for 15 men (62.5%) with sex ratio M/F: 1.67). Mean age was 73.6 years (range 51-89; median: 75). 8 (33.3%) BCC, 7 (29%) CSC, 5 (20.8%) MCC and 4 (16.6%) AC. All the tumors were localized on the face. HT was used because of incomplete excision (n=11), lymph node (LN) involvement/high risk of recurrence (n=7, only CSC and MCC and 1 BCC), non operable lesion (n=4) and recurrent lesion (n=2). The PTV was tumoral bed and/or regional LN with 1 cm margins. Delivered dose for tumour bed was between 50 and 70 Gy and for LN between 50 and 64 Gy. The mean follow-up was 13.7 months (range 239; median: 12). Complete remission was noticed for 21 pts (87.5%); 2 pts (8.3%) died: 1 with inoperable CSC after 5 months follow-up and 1 with recurrent sebaceous carcinoma at 7 month follow-up. 1 pt with MCC had visceral metastases. There was no grade III or IV adverse event, except one grade III mucositis. Grade I or II early radiodermatitis, was respectively diagnosed in 37.5% and 37.5% of patients. Late adverse events were analysed for 20 patients; 70% suffered from limited toxic effects 6 months after the end of the treatment. The characteristics of patients and tumours, HT data, response and tolerance are summarized in the following tables for each kind of tumours (Table 1, 2, 3 and 4). The average doses (minimum, mean, maximum) received by organs at risk (OAR) according to the localization of the tumors are reported in tables 5, 6 and 7.

In external radiotherapy, the use of missing tissue compensation has been proposed for the improvement of dose distributions resulting from radiation beams entering through oblique or irregular surfaces of the patient. The well-known inconveniences related to conventional compensators justify the investigation of alternative techniques such as the use of dynamic multileaf collimators. The combination of a number of software and hardware modules was necessary for the implementation of dynamic collimation for missing tissue compensation. First, a software module that calculates, with a ray-tracing technique, the missing-tissue deficit from computed tomography scans and generates a desired 2D intensity modulation pattern has been developed. Then a second software module that converts the 2D intensity map to a leaf motion plan for practical delivery with dynamic collimators has been implemented. Finally, the existing primary-scatter separation dose model of the authors' TPS had to be extended to account for the intensity modulation generated by the dynamic MLC. As an example of the 'virtual' compensator technique, the MLC sequence that would compensate an arbitrary patient irregular surface has been calculated. Then, film was used to measure the dose on a plane perpendicular to the beam axis at the specified depth of compensation. A comparison between measured and calculated dose distributions shows that an acceptable accuracy in dose calculations can be achieved. Finally a comparison between uncompensated and dynamically compensated fields demonstrates that the 'virtual' compensator was able to flatten the off-axis dose across a plane perpendicular to the beam axis at the depth of compensation.

Objectif Cette etude a evalue le controle local et a distance, la survie et la tolerance suite a une irradiation hautement conformationnelle chez des patients atteints d’un carcinome adenoide kystique sinonasal localement evolue envahissant la base du crâne. Patients et methodes Entre 2010 et 2014, 13 patients atteints d’un carcinome adenoide kystique sinonasal ont ete pris en charge dans notre centre. Le suivi median etait de 12 mois (1 - 47). Le sinus sphenoide etait la localisation la plus courante, puis le sinus maxillaire. La base du crâne etait atteinte chez tous les patients. Dix patients (77 %) ont beneficie d’une chirurgie R1 ou R2 prealable et trois (23 %) etaient atteints d’une tumeur non resecable. Il s’agissait d’une re-irradiation chez deux patients (15 %). La radiotherapie etait pour cinq patients (38 %) une tomotherapie exclusive, pour trois (23 %) une protontherapie exclusive et pour cinq (38 %) une association de tomotherapie et de protontherapie. Les doses delivrees etaient de 70 a 73,8 Gy. Trois patients (23 %) ont recu une chimiotherapie concomitante par cisplatine a la dose de 100 mg/m2. Resultats A 12 mois, le taux de controle local etait de 83 %, celui de survie sans metastase de 75 % et celui de survie globale de 80 %. La tolerance immediate a ete tres bonne, un patient seulement a ete atteint d’une radiodermite de grade III. Comme toxicite tardive a un an, on notait une hypoacousie de grade III pour cinq patients (38 %), homolaterale a la lesion, ainsi qu’une rhinite de grade III chez un patient. Conclusion Notre etude suggere que l’irradiation a doses elevees, a l’aide de technique de radiotherapie hautement conformationnelles (protontherapie et tomotherapie), serait un moyen efficace et sur de traiter les patients atteints de carcinome adenoide kystique sino-nasal localement evolue.

In external radiotherapy, the use of intensity modulated fields has been proposed for tissue and non-homogeneity compensation or for the generation of conformal dose distributions. Multileaf collimators can be employed dynamically for the modulation of the X-ray field in two dimensions. Efficient dynamic collimation became possible due to advances in computer and linear accelerator technology. It presents a number of advantages over conventional methods such as the use of compensators. We have developed a program which calculates, from a given intensity distribution, the motion of the MLC leaves as a function of monitor units, and we have applied it on a Varian linear accelerator with a 40 pair multileaf collimator. The analysis of the experimental results demonstrates the feasibility and the potential of the method.