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Présentation Poster; International audience

JCTCV:22(1), Introduction: After esophagectomy, part of the viscera can migrate through the hiatus to surround the gastric tube, creating hiatal hernias (HH) which eventually lead to abdominal occlusion and bowel ischemia. Methods: This retrospective multicenter study investigated the diagnosis, surgical management and follow-up of HH after esophagectomy in French-speaking European departments. Results: From 2000 to 2016, 19 departments performed 6608 esophagectomies. During follow-up, 78 cases of HH (1.2%) required surgery. These were more frequent after the laparoscopic approach than after laparotomy (1.4% vs. 0.7%; p = 0.03). The appearance of HH occurred during early follow-up (≤90 days) for 17 patients (21.5%), 21 underwent surgery during the first year (26.6%) and 41 after the first year (51.9%), with 13, 13 and 17 urgent surgeries, respectively. The surgical approaches included laparotomy (n = 35, 45%), especially when bowel resection was needed, laparoscopy (n = 19, 24%), a thoracic approach (n = 13, 17%) or a thoracophrenolaparotomy (n = 11, 14%). Complications arose in 36 patients, with one death and 13 secondary surgeries (three for secondary HH). Eight patients presented with recurrent HH (between 6 days and 26 months). Conclusion: Development of HH after esophagectomy can have a wide range of presentations, and can lead to thoracic or abdominal complications requiring specialized management.

National audience; Les cancers cutanés non mélanocytaires (appelés carcinomes cutanés) sont les cancers les plusfréquents, et leur prévalence est en augmentation dans l’hémisphère Nord : 20 % des plus de 60 ans sontporteurs de lésions précancéreuses [1]. La chirurgie est le traitement de référence dans la prise en chargethérapeutique de ces cancers et le plus souvent, la résection chirurgicale se fait en « fuseau » (Fig. 1). Cefuseau contient 3 types de tissu cutané dont la nature est évaluée visuellement par le chirurgien (avantdiagnostic définitif par anatomo-pathologie) : lésionnel (« L », partie visible du carcinome cutané), périlésionnel(« PL », marge de sécurité) et non-lésionnel (« NL », extrémités du fuseau).L’essai clinique SpectroLive mené actuellement au CHR Metz-Thionville propose d’évaluer lacapacité de la spectroscopie optique résolue spatialement à caractériser la nature histologique et photobiologiquede ces 3 types de tissus. Le dispositif SpectroLive [2] permet l’acquisition de spectres d’autofluorescence(pics d’excitation entre 365 et 415 nm) et de réflectance diffuse recueillis à 4 distances interfibres: de 0,4 à 1 mm. Le but est d’aider le chirurgien dans son orientation diagnostique visuelle pourdiscriminer plusieurs classes tissulaires d’intérêt clinique : (i) sain, (ii) cancer, (iii) kératose actinique àhaut potentiel évolutif et (iv) kératose à faible potentiel évolutif. Afin d’augmenter le rapport signal àbruit, 3 spectres sont acquis consécutivement sur un même site, pour chacun des 3 types de tissusrencontrés au sein du fuseau chirurgical (L, PL et NL). Les résultats préliminaires montrent unediminution globale du signal entre cancer (site de mesure « L ») et tissu sain (site de mesure « NL »), enRD à toutes les distances inter-fibres (Fig. 1b) comme en auto-fluorescence.

International audience; This work investigates the impact of several levels of optical probe pressure on human skin autofluorescence (AF) and diffuse reflectance (DR) spectra acquired using spatially-resolved optical spectroscopy in vivo and on ex vivo, i.e. exsanguinated, skin samples.

National audience; Cette étude présente une analyse préliminaire de la sensibilité en profondeur de laspectroscopie bimodale résolue spatialement aux modifications des propriétés optiques depeau humaine ex vivo induites par un agent de clarification optique (OCA) à base de sucrose.Le dispositif médical de spectroscopie tissulaire résolue spatialement développé parnotre équipe permet de réaliser sur chaque site tissulaire l’acquisition colocalisée despectres de réflectance diffuse (RD) et de spectres d’intensité d’autofluorescence (AF) enutilisant 5 longueurs d’onde d’excitation (365, 385, 395, 405 et 415 nm). Une sonde multifibrespermet de collecter ces mesures à 4 distances inter-fibres (D1-D4 = 400-1000 μm).Le protocole expérimental met en oeuvre un fantôme hybride bicouches dont la coucheinférieure est un gel d’agarose 1,5% enrichi avec 500 μm de nanoparticules d’AGuIX(R). Lacouche supérieure correspond à un échantillon de peau ex vivo sur lequel la sonde de mesureest posée. Les mesures sont réalisées avant et après application d’un OCA composé de 45 %de PEG400, 5 % de PG et 5 % de sucrose.Les coefficients optiques (absorption μa(lambda) et diffusion μs(lambda)) de l’échantillon de peausont estimés à partir d’une inversion de modèle basée sur un modèle direct de type MonteCarlo multicouches intégrant la fluorescence. La résolution de ce problème inverse prend encompte la dimension spatiale et spectrale des spectres expérimentaux. Des fonctionsparamétriques sont utilisées pour modéliser les coefficients optiques résolus spectralement.Les résultats obtenus avant et après application de l’OCA montrent des modificationssignificatives des amplitudes des spectres de RD et d’AF en fonction des longueurs d’onde etdes distances interfibres qui indiquent que les photons incidents pénètrent plus profondémentet sont moins absorbés et diffusés par la couche de peau. Ces observations sont confirméespar les valeurs estimées des coefficients optiques de la peau avant et après OCA.

The aim of this chapter is to review the experimental and numerical techniques for the estimation of the laser-induced fluorescence (LIF) decay in rare gases using time-correlated single-photon counting. The advantages of single-photon counting technique are discussed by means of measurement uncertainty analysis. In addition, this chapter provides information concerning the application of this technique to filamentary dielectric barrier discharges (DBD) and radiation trapping of the resonant transitions.

International audience; Optical clearing agents’ impact on skin optical properties (OP) was investigated using spatially – resolved bimodal spectroscopy and inverse Monte Carlo modelling. Optical spectra were obtained on an original hybrid model made of ex vivo human skin as a top layer and of agarose and porphyrin based – nanoparticles as a bottom layer. First results are given in terms of estimated absorption and scattering coefficients of skin layer before and after OCA application.

International audience; This course is an overview presentation of main approaches to estimate the optical properties of biological tissues from fibered optical spectroscopy measurements and requiring inverse problem solving.First, the principle of “tissular optical biopsy” will be considered including instrumentation configuration (sources, detectors, multi-fiber optical probe geometry), light-tissue photo-physical interactions in the UV-Visible wavelength range and medical applications.Second, the generic problem of tissue optical parameters estimation (inverse problem solving) in the above mentioned configuration will be expressed and challenges in terms of modelling, forward problem simulation, cost-function and optimization methods will be presented.Third, state-of-the art solutions and results as well as latest and perspective development will be overviewed.

International audience

International audience; Hot air plasma is generated inside a 2.45GHz microwave resonant cavity and is ejected towards a gas conditioning cell at 600 mbar. A flow of 12 liter/min of dry air with a small amount of H$_2$, in order to better detect OH (A-X) spectra for gas temperature measurements, is injected at the entrance of the resonant cavity using an input power of 1 kW. The measurement of absolute density of atomic ground state oxygen is determined using two-photon absorption laser-induced fluorescence (TALIF) spectroscopy for several radial and axial positions of the hot air plasma column which is a post discharge propagating inside the cell. The gas temperature corresponding to the radial and axial positions, where atomic oxygen density is measured, varies between about 3500K in the column axis down to about 2500K in the plasma border. The measured absolute oxygen density using xenon for calibration varies between about 2.1x10$^{17}$cm$^{-3}$ in the axis down to 0.05x10$^{17}$cm$^{-3}$. This leads to a dissociation degree of oxygen inside the post discharge air plasma column lower than the case where only local thermodynamic equilibrium is assumed. This deviation is due to non-thermal equilibrium effects that can be associated to the not yet achieved relaxation of the long-lived excited species during such post discharge stage.

National audience

National audience; PURPOSE: Surgical resection remains the standard treatment for patients with resectable retroperitoneal sarcomas. The aim of this study was to retrospectively analyse the outcomes of patients with primary retroperitoneal sarcoma. PATIENTS AND METHODS: We analysed data of 50 patients with primary retroperitoneal sarcoma who underwent curative-intent resection from 1975 to 2008. External beam radiotherapy and chemotherapy were delivered postoperatively. Demographics, surgical, pathological variables and chemo/radiation therapy were analysed as prognosis factors. RESULTS: There were 22 males and 28 females (mean age 54±13years). Surgery required visceral resections in 30 patients. There were 16 leiomyosarcomas, 25 liposarcomas and eight other sub-types. Twenty-one patients had clear surgical margins. Twenty-eight patients received postoperative external beam radiotherapy (median 45Gy) and 15 received chemotherapy. At the end of the follow-up (median 55months), local recurrence occurred in 39% (n=14) among R0/R1 resection group (n=36). Postoperative external beam radiotherapy tends to increase the time of local recurrence from surgery (27 vs. 13months, P=0.05). The overall survival rates were 81%, 55% and 46% at 1, 3 and 5years, respectively. Although R0 resection (P=0.01), well tumour differentiation (P=0.004) and postoperative external beam radiotherapy (P=0.02) significantly influenced overall survival in univariate analysis, only R0 resection was an independent prognostic factor in a multivariate analysis. CONCLUSION: We confirm the pre-eminence of radical surgery with negative margins as major prognostic factor and the benefit of postoperative radiotherapy.

Background: The biopsy of the sentinel lymph nodes in breast cancer patients is now strongly recommended for the definition of the further therapeutic strategy. Although this approach has strong advantages, it has its own limitations (manipulation of radioactive products and possible anaphylactic reactions to the dye). As recently proposed, these limitations could in principle be by-passed if semiconductor nanoparticles (quantum dots or QDs) were used as fluorescent contrast agents for the in vivo imaging of sentinel lymph nodes [1]. QDs are fluorescent nanoparticles with unique optical properties like strong resistance to photobleaching, size dependent emission wavelength, large molar extinction coefficient and good quantum yield [2]. Most synthesized QDs are composed of toxic heavy metals (Cd, Te, Se,...) and as such could not be used in the clinical context. Recently, we have demonstrated excellent imaging properties of Cd-free QDs for in vivo lymph nodes detection along with the greatly diminished acute inflammation in healthy rodents [3, 4]. Far before the clinical settings could be envisaged, the study on biodistribution of CuInS2/ZnS QDs in pre-clinical models and the possibility of visualization of lymph nodes upon metastatic dissemination is mandatory. Material and Methods: In vitro studies: The toxicity of CuInS2/ZnS core/shell QD on red blood cells has been tested using the haemolysis test. Red blood cells were incubated during 2h with different concentration of QDs and the release of haemoglobin was measured by spectrophotometry. In vivo studies: Healthy or tumor-bearing mice received 20 μL of 1 μM CuInS2/ZnS core/shell QD solution subcutaneously in the right anterior paw. Right axillary lymph nodes (RALN) were visualized using a near-infrared imaging system (Fluobeam™) and healthy animals were sacrificed at different time points after QDs injection. Organs, blood and excretions were collected and their indium content was measured by ICP-MS. The sentinel lymph node of tumor-bearing mice was imaged by fluorescence and the metastatic involvement of lymph nodes was assessed by the measurement of cytokeratin 19 by RT-qPCR or immunohistochemistry. Results and Discussion: In vitro assessed toxicity: No haemolysis of red blood cells was detected in the range of concentrations of CuInS2/ZnS QDs from 25 to 150 nM, while Cd-based QDs induced 50% of hemolysis with already 56.3 nM (data not shown). In vivo studies: CuInS2/ZnS QDs were observed in RALN as soon as 5 min (Fig. 1) and up to 7 days after the subcutaneous injection of QD in the right anterior paw by in vivo NIR fluorescence imaging.

International audience; Le système d’économie planifié favorisait l’industrie d’armement. En 1990, l’investissement militaire représentait le tiers de l’investissement national. La transition économique a provoqué une crise de la production de ce secteur, faute de commandes spécifiques nationales. Avec l’arrivée au pouvoir de Wladimir Poutine, l’industrie d’armement a connu un sursaut et une modernisation, tout comme les secteurs économiques stratégiques de l’énergie et des métaux précieux et l’industrie de l’armement. L’effort principal porte sur la mise en place d’une puissance nucléaire compétitive et régulée, mais aussi sur l’exportation des armes en vue de réduire le poids du fardeau national de la défense. L’armement devient alors un produit à dimension hautement politique. Dans ce contexte, la Russie a accepté une réduction significative des armes nucléaires dans le cadre des accords de Prague. Elle est redevenue une puissance de premier plan, car la possession de cette arme lui donne une place unique dans les discours internationaux engageant les États-Unis.

Semiconductor nanocrystals, or quantum dots (QDs) have the potential to significantly impact the performance of near infrared fluorescence imaging for biomedical research, diagnostics and optically assisted surgery. For example, QDs could be applied to detection of the sentinel lymph node, the status of which is a key prognostic factor for treatment of many types of cancer. Unfortunately, QDs emitting in the near infrared have been until recently composed of toxic compounds (Cd, Pb, Hg, Te, As...). The potential long term release of these toxic elements in the body has thus been a major obstacle to the QD clinical use, but would also represent an important hurdle for large scale optoelectronic applications. Here we present the synthesis and optical characterization of core and core-shell QDs based on CuInS2 and CuInSe2 that do not contain any toxic heavy metals. Their emission is tunable in the whole near infrared imaging window from 600 nm to 1100 nm. Growth of a ZnS shell around the CuInS2 and CuInSe2 cores increases the fluorescence quantum yield up to 60 % in organic solvents. Structural, composition and optical characterization of these QDs suggest that photoluminescence occurs from defect states inside the QD core. Core/shell QDs maintain their fluorescence properties after solubilisation in water and for long periods of time in vivo. We demonstrate their use for in vivo imaging and detection of regional lymph nodes in mice. Interestingly, CuInS2 -based QDs show a much reduced in vivo toxicity compared to CdTeSe/CdZnS QDs. In addition, we present the synthesis of novel multimodal I-III-VI2 QDs based on doping of near infrared CuInS2/ZnS QDs with paramagnetic Mn2+ ions. We characterize the structural and optical properties of these novel probes. The level of Mn doping is examined under varying synthesis conditions using elemental analysis and electron paramagnetic resonance. SQUID magnetic measurements show the super-paramagnetic behaviour of these nano-particles. These Mn-doped CuInS2/ZnS QDs constitute promising compact nano-probes for multimodal magnetic resonance imaging and near infrared fluorescence and could be useful for whole body pre-clinical MRI mapping and intra-operative optical tracking.

National audience

International audience; Both photodiagnosis (PD) and photodynamic therapy (PDT) are based on the use of a photosensitizer (PS) molecule, that upon illumination either emits fluorescence (PD) or interacts with reactive oxygen species (ROS) to kill the host cell (PDT). A serious limitation is the absence of specific cancer targeting, resulting in false positive results in PD and excessive tissue destruction in case of PDT, which can provoke life threatening situations. To partially overcome these constraints, incorporation of the active compound into nanoparticle platforms can be proposed. Our group is currently investigating silica based NIR fluorescent nanoparticles in an orthotopic mice breast cancer model. Following subcutaneous or intratumor injection, those particles are selectively retained in the first draining lymph node, so called sentinel lymph node (SLN). This fluorescence can be real time monitored with appropriate NIR imaging tools. Fluorescence diagnosis of bladder cancer with ALA has been EC approved but the specificity is very low. The use ALA dendrimers has been shown in vivo studies in a rat bladder cancer model, to dramatically reduce the amount of false positive fluorescence as well as providing a much deeper penetration of the drug in case of invasive bladder cancer. Solid tumors are composed by parenchymal cells, irrigated by pathological vasculature. With regard to the short life time of ROS, the compartment hosting the PS is the exclusive target of the illumination. Simultaneous presence of PS in of both compartments can be obtained by two separate IV administrations at very short or longer time intervals before single illumination. Complete tumor response, mainly through apoptosis, was obtained in vivo. Embedding of active drugs in liposomes is another possibility for passive targeting of tumors. Liposomal formulations of PS enable a more selective and faster accumulation of drugs in the tumors, with a faster clearance, together with a better therapeutic efficacy. Comprehension of the transport kinetics of the PS from the vessels towards extravascular structures is essential for optimizing clinical protocols. We have observed different redistribution patterns to plasma components according to liposomal composition in vitro. Our ongoing studies aim the visualization of these processes in real time in vivo using the chick chorio allantoic membrane (CAM) model.

s published in European Journal of Surgical Oncology (EJSO), Volume 36, Issue 9, Pages 793-932, September 2010; Background: Phyllodes tumour of the breast are fibroepithelial neoplasms which have for peculiarity local recurrence and occasionally metastatic scattering. Material and Methods: A retrospective review of medical records from 120 patients treated for a phyllode tumour in Alexis Vautrin Center from January 1984 to December, 2004 was realized. Histological samples from patients were reviewed by the study pathologist, who determined the phyllodes tumour grade and margin status. Results: Ninety one tumours were begnin (76 %), 15 borderline (12.5 %) and 14 ma- lignant (12 %). The mean tumour diameter was 2.5 cm (range, 0.8 e 17 cm). The mean follow-up was of 105 months (range, 8 e 288 months) . Seven patients pre- sented a local recurrence after a median time of 35 months (range, 17-136 months) and 1 patient revealed a metastatic recurrence. The global survival, the specific sur- vival and survival without local second recurrence were respectively 95 %, 99 % and 92 % in 10 years. The histological rank (p 10/10 HPF (p

s published in European Journal of Surgical Oncology (EJSO), Volume 36, Issue 9, Pages 793-932, September 2010; Objectives: To compare clinical and tumoural characteristics of patients with a breast cancer, according to the use of hormone replacement therapy. Material and Methods: Our study is a retrospective study about 621 cases of breast cancer among postmenopausal women, initially treated by surgery in the “Centre Alexis Vautrin” between on January 1, 2002 and December 31, 2004. Results: The population was divided into two samples according to the exposure to the hormone replacement therapy. 219 women were exposed to the HRT at the time of the diagnosis or had stopped it since less than 3 years and 402 women were none exposed or having stopped the treatment more than 3 years before the diagnosis. The exposed patients present a significant degree of small size cancers, and well dif- ferentiated. On the other hand, it wasn't highlighted a difference of lymph node inva- sion or hormonal receptivity. From the histological point of view, there exists in the group with THS, more lobular cancer or mixed (ductal cancer associated with a lobular cancer). On the plan of the medical monitoring, we note a more important follow-up and screening mammography in the group with THS. No significant difference in sur- vival was highlighted because of a population represented in more than 90% by tu- mours pT1-pT2 and a low number of events. Conclusion: Even if there is recognized that THS increases the risk of breast cancer, this one remains weak (variable of 1.06 to 2 according to the studies). Many observa- tional studies showed that breast cancers appearing under THS are favorable histopro- nostic, which we also find in our series. The balance benefit/risk of the THS “to the Frenchwoman”, by privileging the cutaneous oestrogens and micronized progesterone, remains favorable to its regulation for the recently me ́nopaused patients, which pres- ents a climateric syndrome or a high risk of osteoporosis.

s published in European Journal of Surgical Oncology (EJSO), Volume 36, Issue 9, Pages 793-932, September 2010; Background: Cervical cancer, which is a consequence of infection, is the second lead- ing cause of cancer worldwide in women. Currently, several prognostic factors of cer- vical cancer are identified in the literature. Some risk factors are still being discussed, such as patient's age at diagnosis and tumour histological type. Therefore, we evaluate patient's age at diagnosis and tumour histology as prognostic factors of primary inva- sive cervical cancer. Material and Methods: We performed a prospective cohort study including 861 pa- tients treated for cervical cancer between 1990 and 2003 at the Alexis Vautrin Centre (Vandœuvre-le`s-Nancy, France). Follow-up was conducted until 1 January 2009. Sur- vival rates were calculated using the Kaplan-Meier survival curves and compared by the log-rank test. Results: The 5-years specific survival rate of women aged

s published in European Journal of Surgical Oncology (EJSO), Volume 36, Issue 9, Pages 793-932, September 2010; Background:: Uterine sarcomas include a heterogeneous group of rare tumours that have an aggressive clinical behaviour and a poor prognosis. A retrospective analysis of patients with uterine sarcoma was undertaken to assess prognostic factors and treat- ment related outcomes. Methods and Materials: Medical records were reviewed and data collected on all uterine sarcomas treated during a 30-year period (1975-2005) at Alexis Vau- trin Center, Nancy, France. Results: One hundred and seventy patients met the study requirements: 92 were diag- nosed as carcinosarcomas (CS), 44 as leiomyosarcomas (LMS), 23 as endometrial stromal sarcomas (ESS) and 11 as undifferenciated sarcomas. First-line treatment was surgery in 86.5 % and 77.7 % patients were treated by adjuvant therapies. The mean duration of follow-up was 78 months. The 2 and 5-year overall survival rates were 53 and 39.1 %, with a median survival of 26.3 months. CS had the lower 5- year survival rate (36.6 %) but without significant difference with the other histologies (LMS 49.9%; ESS 57.5 %). Stage, lymph node involvement and myometrial invasion depth were significant prognostic factors in carcinosarcomas. Stage, menopausal sta- tus and tumour grade were significant prognostic factors in leiomyosarcomas and en- dometrial sarcomas. Regarding adjuvant treatment, radiotherapy and brachytherapy had a significant impact on local control without incidence on survival. Conclusion: In patients with uterine sarcomas, carcinosarcomas tend to present a more aggressive disease with different prognostic factors and different treatment needed. Pelvis irradiation is recommended but prognosis remains poor. The role of adjuvant chemotherapy is currently under investigation.