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The duration of stereotactic body radiotherapy (SBRT) for early-stage non-small cell lung cancer (NSCLC) may affect patient outcomes. We aimed to determine the impact of a continuous versus discontinuous SBRT schedule on local control (LC) and overall survival (OS) in NSCLC patients.Consecutive NSCLC stage I patients (475) treated with SBRT in four centers were retrospectively analyzed. The delivered dose ranged from 48 to 75 Gy in 3-10 fractions. Based on the ratio between the treatment duration (TD) and number of fractions (n), patients were divided into two groups: continuous schedule (CS) (TD ≤ 1.6n; 239 patients) and discontinuous schedule (DS) (TD 1.6n; 236 patients). LC and OS were compared using Cox regression analyses after propensity score matching (216 pairs).The median follow-up period was 41 months. Multivariate analysis showed that the DS (hazard ratio (HR): 0.42; 95 % confidence interval (CI): 0.22-0.78) and number of fractions (HR: 1.24; 95 % CI: 1.07-1.43) were significantly associated with LC. The DS (HR: 0.67; 95 % CI: 0.51-0.89), age (HR: 1.02; 95 % CI: 1-1.03), WHO performance status (HR: 2.27; 95 % CI: 1.39-3.7), and T stage (HR: 1.4; 95 % CI: 1.03-1.87) were significantly associated with OS. The 3-year LC and OS were 92 % and 64 % and 81 % and 53 % for DS and CS treatments, respectively (p 0.01). Cox analysis confirmed that the discontinuous SBRT schedule significantly increased LC and OS.DS is associated with significantly improved LC and OS in early-stage NSCLC patients treated with SBRT.

Brachytherapy (BT), a type of focal cancer radiation therapy, delivers a highly focused dose of radiation to localized tumors, sparing surrounding normal tissue. Brachytherapy has been used to treat gynecologic malignancies, particularly cervical cancer, for over 100 years. From the first gynecologic brachytherapy treatments in the early 20th century to the modern era, significant transformations have taken place, largely due to advances in technology. The development of high-dose-rate sources, remote afterloaders, new applicators, and three-dimensional image guidance has increased tumor dose and, consequently, local control and survival, reinforcing brachytherapy's role as an integral component of gynecologic cancer treatment. Current research efforts involving biomarker research, integration of new imaging modalities, radiosensitizing therapies are aimed at further personalizing the dose delivered in BT to further improve local control and reduce treatment's related toxicities.

Recent technological developments enable the detection and quantification of circulating tumour DNA in the blood, with potentially major clinical implications, particularly for cancers treated with curative intent. Circulating tumour DNA has a potential impact before, during and after treatment. If limitations of this approach remain, requiring further development, it is important to know the principles and applications in view of the potential impact on the clinical practice. In this review, we will discuss the current detection methods, then the place of circulating tumour DNA in oncology and more particularly in radiotherapy.

Bladder dose constraints in case of conformational radiotherapy/intensity-modulated radiotherapy and stereotactic radiotherapy are reported from the literature, in particular from the French radiotherapy society RECORAD recommendations, according to the treated pelvic tumor sites. The dose-volume effect on urinary toxicity is not clearly demonstrated, making difficult to establish absolute dose constraints for the bladder. In case of high-dose prostate cancer radiotherapy, the bladder dose constraints are: V60Gy

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.

Recent technological developments enable the detection and quantification of circulating tumour DNA in the blood, with potentially major clinical implications, particularly for cancers treated with curative intent. Circulating tumour DNA has a potential impact before, during and after treatment. If limitations of this approach remain, requiring further development, it is important to know the principles and applications in view of the potential impact on the clinical practice. In this review, we will discuss the current detection methods, then the place of circulating tumour DNA in oncology and more particularly in radiotherapy.

Radiotherapy of abdominopelvic primary or secondary lesions in conformational or stereotactic techniques is in full development. The small bowel is highly sensitive to irradiation and is the main organ at risk limiting prescription doses. This literature review aims to define the dose constraints to the small bowel and the duodenum in conformational and stereotactic body radiotherapy. The small bowel including the duodenum, jejunum and ileum is delineated on the simulation scanner. The radio-induced intestinal toxicities are acute related to the cellular depopulation of the intestinal mucosa, and late of more complex pathophysiology associating depletion in stem cells, microangiopathy, chronic inflammation and fibrosis. The main predictive factor of intestinal toxicity is the dose-volume ratio. In conformational radiotherapy, the dose constraints to the duodenum are: V25Gy45% and V35Gy20%. The jejunum and ileum dose constraints are for delineation by intestinal loop or peritoneal cavity respectively: V15Gy275mL or V15Gy830mL and V45Gy150mL. In stereotactic body radiotherapy, small bowel dose constraints depend on fractionation and are defined on a small volume and on a maximum dose at one point. Intestinal toxicity is also dependent on factors intrinsic to the patient and radiosensitizers such as targeted therapies or chemotherapies. With the development of new techniques allowing dose escalation on the tumour and the development of inverse planning, the definition of dose constraints to the small bowel is essential for current practice.

Introduction et but de l’etude L’objectif de cette etude etait de developper et d’evaluer une signature radiomique en utilisant l’imagerie tomographique par emission de positons (TEP/TDM) chez des patients atteints d’un cancer du poumon non a petites cellules traites par irradiation stereotaxique. Materiel et methodes Il s’agit d’une etude retrospective multicentrique portant sur 87 patients atteints d’un atteints d’un cancer du poumon non a petites cellules de stade T1-T2 traite dans quatre centres du Grand Ouest. Les patients des trois premiers centres (n = 27, 29 et 8) constituaient le groupe d’apprentissage, et ceux du quatrieme (n = 23) le groupe de validation. Le critere d’evaluation principal etait le controle local. En tout, 184 parametres radiomiques ont ete extraits (92 de chaque modalite) et sept parametres cliniques, histologiques et therapeutiques ont ete consideres. En raison des differents scanographes et protocoles d’acquisition des institutions, nous avons utilise la methode ComBat pour harmoniser les parametres de texture. Resultats et analyse statistique En analyse unifactorielle, deux parametres issus de la TEP et deux de la scanographie etaient significativement predictifs du controle local, a l’inverse des variables cliniques. Le meilleur modele predictif du groupe d’apprentissage etait obtenu en associant deux parametres TEP (IC2 et strength), avec une sensibilite de 100 % et une specificite de 88 %, et un hazard ratio indefini (p Conclusion Notre etude a permis d’identifier deux parametres de textures derives de la TEP/scanographie comme facteurs predictifs independants associes a la recidive locale chez les patients atteints d’un cancer du poumon non a petites cellules traites par irradiation stereotaxique. Ce modele merite d’etre confirme sur une cohorte plus consequente et pourrait etre utilise en clinique pour guider une eventuelle escalade de dose.

The knowledge of inter- and intrafraction motion and deformations of the intrapelvic target volumes (prostate, seminal vesicles, prostatectomy bed and lymph nodes) as well as the main organs at risk (bladder and rectum) allow to define rational clinical to planning target volume margins, depending on the different radiotherapy techniques and their uncertainties. In case of image-guided radiotherapy, prostate margins and seminal vesicles margins can be between 5 and 10mm. The margins around the prostatectomy bed vary from 10 to 15mm and those around the lymph node clinical target volume between 7 and 10mm. Stereotactic body radiotherapy allows lower margins, which are 3 to 5mm around the prostate. Image-guided and stereotactic body radiotherapy with adequate margins allow finally moderate or extreme hypofractionation.

Objectif de l’etude Les objectifs etaient de quantifier les deplacements vasculaires pelviens en cas de RCMI prostatique pour en deduire un volume cible interne (ITV) puis un volume cible previsionnel (PTV), dans une approche de radiotherapie guidee par l’image (IGRT) des aires ganglionnaires avec recalage osseux. Materiel et methode Vingt patients pris en charge pour une RCMI prostatique ont eu une scanographie de simulation, ainsi que sept scanographies hebdomadaires. Les principaux vaisseaux pelviens et la vessie ont ete manuellement delinees : iliaque commune, iliaque externe et iliaque interne. Toutes ces structures ont ete recalees sur la scanographie de simulation. Les lignes centrales de chaque vaisseau ont ete creees grâce a une station dediee a la chirurgie endovasculaire. Pour evaluer les deplacements vasculaires, la distance entre chaque point echantillonne de la ligne centrale de chaque vaisseau de la scanographie de simulation et de la scanographie hebdomadaire a ete calculee dans les trois directions de l’espace. Les marges de l’ITV correspondaient aux valeurs couvrant le deplacement maximal des lignes centrales pour 95 % des patients, dans chacune des directions et pour chaque vaisseau. Resultats Les marges de l’ITV (mm) dans les directions laterales, anteroposterieures et craniospinales etaient respectivement pour l’iliaque commune de 4,9, 8,5 et 5,4 mm, pour l’iliaque externe de 6,7 10,2 et 8,8 mm, et pour l’iliaque interne de 4,7, 4,6 et 4,3 mm. Ces deplacements vasculaires etaient fortement correles avec les variations de volume vesical (coefficient de Pearson r > 0,5) pour 20 a 50 % des patients selon les vaisseaux. Conclusion La marge de l’ITV a partir des volumes cibles antomocliniques (CTVs) des aires ganglionnaires pelviennes devrait etre, selon les directions de l’espace, de l’ordre de 5 a 8 mm pour l’iliaque commune, de 7 a 10 mm pour l’iliaque externe et 5 mm pour l’iliaque interne. Pour definir le PTV, une marge additionnelle autour de l’ITV est prise, tenant compte de l’erreur liee au recalage osseux (environ 2 mm). Le deplacement des vaisseaux peut etre correle avec le volume de la vessie.

Objectif de l’etude Des surdosages peuvent survenir dans les organes a risque au cours d’une radiotherapie conformationnelle avec modulation d’intensite (RCMI) prostatique. L’objectif du travail etait d’evaluer sur le plan dosimetrique le benefice d’une strategie de radiotherapie adaptative guidee par la dose par rapport a une radiotherapie guidee par l’image. Materiel et methode Doses planifiees et cumulees ont d’abord ete comparees pour 24 patients ayant recu une RCMI guidee par l’image prostatique avec tomographie conique quotidienne [1] , permettant de selectionner les quatre patients qui avaient le surdosage le plus important dans les organes a risques. La radiotherapie adaptative guidee par la dose consistait en une ou plusieurs replanification(s) declenchee(s) grâce au suivi de la dose cumulee delivree en cours de la radiotherapie. La premiere etape consistait a estimer la dose cumulee seance apres seance. La replanification a ete declenchee si un surdosage superieur a 5 % par rapport a la planification etait observe sur la V72 Gy (VxGy : volume recevant x Gy) de la paroi rectale et/ou la V70 Gy de la paroi vesicale. En cas de declenchement, la seconde etape consistait a identifier la fraction conduisant a la derive dosimetrique la plus importante pour utiliser la tomographie conique correspondant pour la replanification. Le traitement se poursuivait en delivrant la dose replanifiee, avec repetition du processus si le surdosage n’etait pas compense. Resultats Pour les quatre patients, une seule replanification durant de la premiere semaine de traitement a ete necessaire pour corriger les surdosages des organes a risque. Pour la paroi rectale, la radiotherapie adaptative guidee par la dose reduisait en moyenne la V72 Gy de 3,2 % (5,6 % au maximum) et la dose moyenne de 6,8 Gy (13,7 Gy au maximum). Pour la paroi vesicale, la radiotherapie adaptative guidee par la dose reduisait en moyenne la V70 Gy de 5,9 % (9,5 % au maximum) et la dose moyenne de 9,0 Gy (16,5 Gy au maximum). La radiotherapie adaptative guidee par la dose augmentait la D99 % prostatique de 0,4 Gy en moyenne (0,8 Gy au maximum). Conclusion La radiotherapie adaptative des cancers de prostate avec modulation d’intensite guidee par l’image consiste a declencher une replanification basee sur un suivi de la dose cumulee dans les organes a risque, permettant de corriger les surdosages survenant seulement chez 10 a 15 % des patients.

Objectif de l’etude L’objectif etait de determiner l’impact en termes de controle local et de survie globale d’un schema d’irradiation continu par comparaison a discontinu (un jour sur deux) dans le cadre d’une irradiation en conditions stereotaxiques d’un carcinome bronchique non a petites cellules de stade I. Materiel et methode Cent quatre-vingt-dix-huit patients consecutifs dans deux centres pris en charge entre janvier 2007 et septembre 2016 pour un carcinome bronchique non a petites cellules de stade I traite par irradiation en conditions stereotaxiques ont ete retrospectivement inclus. La dose delivree variait de 48 a 60 Gy en trois a six fractions (biological effective dose [BED] mediane de150 Gy) par un accelerateur lineaire avec une technique d’asservissement respiratoire ou une machine dediee (CyberKnife®). Les patients ont ete separes en deux groupes selon le schema therapeutique : continu (rapport etalement/nombre de fractions inferieur a 2) ou discontinu (rapport superieur ou egal a 2). Les donnees de survie, de controle local et de toxicite ont ete recueillies. Resultats Sur l’ensemble de la cohorte, le suivi median etait de 34 mois. Cent cinquante-huit patients ont ete traites selon le schema continu et 40 selon le schema discontinu. Les deux groupes etaient comparables sur les principaux facteurs confondants (âge, statut tumoral, sexe, histologie). La probabilite de controle local a 2 ans etait de 91 % (groupe continu) contre 93 % (groupe discontinu, p = 0,13). Aucun parametre clinique ou lie au traitement n’etait correle avec le controle local. Pour ce qui concerne la survie globale, le schema discontinu etait superieur apres analyse multifactorielle : probabilite de survie globale a 2 ans 77 % contre 65 % (p = 0,035). Le profil de toxicite aigue sur le plan pulmonaire etait identique entre les deux groupes, avec moins de 3 % de cas de grade 3 ou plus. Conclusion Le schema therapeutique, continu ou discontinu, ne semble pas avoir d’impact sur l’efficacite du traitement en termes de controle local ni sur la toxicite aigue pulmonaire. Neanmoins, il semble exister une difference significative en termes de survie globale, sans que celle-ci ne soit expliquee par la toxicite aigue. Nous proposons la realisation d’un protocole de phase III evaluant l’efficacite du schema continu par comparaison a discontinu lors de la realisation d’une radiotherapie en conditions stereotaxiques.

The diet of Leisler's bat Nyctalus leisleri was investigated by analysis of droppings collected from six mainly pastoral sites in Ireland, two sites in England (one mainly pastoral, one arable predominating) and three in Germany (in forest), and comprised mainly medium-sized and small insects caught in flight, many of which were probably from swarms. There was a major pastoral prey component, indicated mainly by Scathophaga stercoraria, Scarabaeoidea and associated Acari, at the Irish sites (estimated as 29–55%) and the English pastoral site (22%), but this was less significant elsewhere (1–12%). Insects with aquatic larvae (Ephemeroptera, Trichoptera, Chironomidae/Ceratopogonidae, Culicidae) often made up an important part of the diet (4–39%). Another distinct component, the Lepidoptera, Hemerobiidae, Chrysopidae and Ichneumonidae, which were all intercorrelated in the results, possibly indicates feeding near trees. This component was most important at the German (36–63%) and English arable (30%) locations, but of less significance at the English pastoral (11%) and Irish (2–19%, mean 6%) ones. The diets in Germany were otherwise diverse.

The temporal and spatial distribution of planktonic protozoa of Esthwaite, a eutrophic lake, was investigated at 7–10 day intervals between February to October 1988. Sarcodine protozoa were of little significance, the plankton was dominated by ciliates and flagellates. Ciliate density peaked in late May to early June with densities reaching 9.2 × 103 1-1. There was considerable variation in spatial distribution and greatest species diversity occurred in March/April. After the establishment of summer stratification the planktonic ciliates were confined to water of >25% oxygen saturation in the water column. Oligotrichs, particularly the genus Strombidium and tintinnids, and peritrichs dominated the ciliate assemblages. There was no correlation between chlorophyll a concentrations and ciliate numbers, but a correlation was apparent between ciliate numbers and flagellate density. There were significant differences between the protozooplankton communities at the different sampling sites in the lake.

The aim of this retrospective multicentric study was to develop and evaluate a prognostic 18F-FDG PET/CT radiomic signature in early-stage non-small cell lung cancer patients treated with stereotactic body radiotherapy (SBRT). Methods: Patients from 3 different centers (n = 27, 29, and 8) were pooled to constitute the training set, whereas the patients from a fourth center (n = 23) were used as the testing set. The primary endpoint was local control. The primary tumor was semiautomatically delineated in the PET images using the fuzzy locally adaptive Bayesian algorithm, and manually in the low-dose CT images. In total, 184 Image Biomarkers Standardization Initiative-compliant radiomic features were extracted. Seven clinical and treatment parameters were included. We used ComBat to harmonize radiomic features extracted from the 4 institutions relying on different PET/CT scanners. In the training set, variables found significant in the univariate analysis were fed into a multivariate regression model, and models were built by combining independent prognostic factors. Results: Median follow-up was 21.1 mo (range, 1.7-63.4 mo) and 25.5 mo (range, 7.7-57.8 mo) in training and testing sets, respectively. In univariate analysis, none of the clinical variables, 2 PET features, and 2 CT features were significantly predictive of local control. The best predictive models in the training set were obtained by combining one feature from PET (Information Correlation 2) and one feature from CT (flatness), reaching a sensitivity of 100% and a specificity of 96%. Another model combining 2 PET features (Information Correlation 2 and strength) reached sensitivity of 100% and specificity of 88%, both with an undefined hazard ratio (P < 0.001). The latter model obtained an accuracy of 0.91 (sensitivity, 100%; specificity, 81%), with a hazard ratio undefined (P = 0.023) in the testing set; however, other models relying on CT radiomic features only or the combination of PET and CT features failed to validate in the testing set. Conclusion: We showed that 2 radiomic features derived from 18F-FDG PET were independently associated with local control in patients with non-small cell lung cancer undergoing SBRT and could be combined in an accurate predictive model. This model could provide local relapse-related information and could be helpful in clinical decision making.