Evaluation de l efficacité des traitements néoadjuvants des cancers du sein en IRM morphologique et fonctionnelle

PARIS7-Xavier Bichat (751182101) / SudocSudocFranceF

Valeur prédictive de l'IRM de diffusion dans la réponse au traitement néoadjuvant du cancer du sein

LE KREMLIN-B.- PARIS 11-BU Méd (940432101) / SudocSudocFranceF

QUANTIFICATION DE LA MICROCIRCULATION TUMORALE EN IRM A L'AIDE D'AGENTS DE CONTRASTE DIFFUSIBLE ET MACROMOLECULAIRE CHEZ LE RAT

PARIS-BIUM (751062103) / SudocCentre Technique Livre Ens. Sup. (774682301) / SudocSudocFranceF

Méthodes d'analyse de la microcirculation tumorale en IRM

La néoangiogénèse est impliquée dans le développement des tumeurs. Certains facteurs stimulant l angiogénèse ont été isolés et peuvent être inhibés. La surveillance de l activité de ces thérapies inhibitrices, souvent cytostatiques, ne peut se baser sur une observation morphologique. L étude fonctionnelle de la microcirculation est possible en IRM grâce à l analyse de la pharmacocinétique de traceurs dans la tumeur.L activité d une thérapie antiangiogénique a été surveillée en IRM grâce au Spin Labeling (ASL) couplé à une suppression du bruit de fond. Cette technique permet de quantifier la perfusion tissulaire, grâce à un marquage électromagnétique des protons du sang. L ASL a permis de distinguer dès le 1er mois les patients répondeurs des patients en progression, ce que les mesures morphologiques ne révélaient qu à 3 mois. L analyse de la perméabilité capillaire par l analyse dynamique des rehaussements (ADR) tissulaires et artériels après injection de produit de contraste a été optimisée grâce à une séquence double écho dont la pondération était adaptée aux concentrations mesurées : T2* pour les concentrations élevées et T1 pour les basses. Cette technique a permis de réduire de 58% l erreur d estimation de la perméabilité capillaire. Le développement d une technique de mesure des temps de relaxation en une apnée a permis d améliorer les estimations de perfusion (ASL) et de perméabilité (ADR) en évitant d utiliser des valeurs de T1 tumorales approximatives lors de la quantification.En mesurant la perfusion et la perméabilité tumorale, cibles des traitements antiangiogéniques, l ASL et l ADR se présentent comme des méthodes attractives pour le suivi de ces thérapies.Angiogenesis plays a key role in tumor growth. New approaches to treat cancer by interfering with angiogenesis stimulating factors are now available. However, clinicians need new surrogates of antiangiogenic activity. Tumor size changes occure 2 or 3 month after the beginning of the treatment, which is to late. Functional analysis of tracer kinetic in tissue in MRI may be an attractive alternative.Antiangiogenic activity of a VEGF receptor inhibitor, was evaluated by tumor blood flow, assessed by arterial spin labeling (ASL) with background suppression. Preliminary results reveal a significant correlation (Spearman r = 0.90, p = .0002) between the change in blood flow at 1 month and change in tumor size measured at 4 months or the time of disease progression. A capillary permeability assessment in dynamic contrast enhancement (DCE) was optimized using a dual gradient echo sequence. This dual sequence was sensitive to high concentration thanks to T2* weighted images and to low concentrations with T1 weighted slices. The use of this sequence leads to reduce by 58% the permeability measurements.The development of a new technique to assess to relaxation time in the body within a single breath hold may improve perfusion and permeability measurements. Real relaxation time can be used for quantification instead of theoretical values, reducing systematic error.ASL and DCE have promise as early predictors of clinical response to antiangiogenic therapies and may help to identify non-responding patients.ORSAY-PARIS 11-BU Sciences (914712101) / SudocSudocFranceF

Performances des biopsies médiastinales sous contrôle tomodensitométrique

Introduction : Les biopsies sous contrôle tomodensitométrique sont actuellement de plus en plus employées pour le diagnostic des masses médiastinales. Le but de l étude était de confirmer les bonnes performances diagnostiques des biopsies médiastinales scanno-guidées, de démontrer que les complications sont peu nombreuses et d identifier les raisons d échec de certaines procédures afin d améliorer la rentabilité diagnostique. Matériel et méthodes : 308 biopsies médiastinales consécutives réalisées de 2006 à 2011 dans le service d imagerie médicale de l hôpital Saint Louis (Paris) ont été analysées rétrospectivement. Pour chaque procédure, il a été recueilli le contexte clinique (indication, localisation et taille de la masse), les caractéristiques du geste (voie d abord, type d aiguille, nombre de prélèvements, complications, durée), et les résultats anatomo-pathologiques. Résultats et discussion : Dans 82,5% des cas (254 procédures), la biopsie médiastinale sous contrôle tomodensitométrique a mené à l obtention d un diagnostic permettant de déterminer une attitude thérapeutique. L efficacité de la biopsie augmente significativement avec la taille de la lésion. Il n a pas été mis en évidence d autres facteurs influençant l efficacité du geste. La survenue de complications, essentiellement hémorragiques, a été observée dans 7,5% des cas, soit 23 patients. Seuls 3 patients ont du bénéficié d une hospitalisation supérieure à 12h. Il n a pas été mis en évidence de lien statistique entre la survenue de complication et les caractéristiques de la lésion cible, ni avec les paramètres techniques du geste. Les taux d efficacité et de complication des procédures obtenus sont comparables à ceux antérieurement publiés dans la littérature. Conclusion : la biopsie médiastinale sous contrôle tomodensitométrique est une procédure efficace et sûre, et doit être indiquée en première intention avant le recours à la médiastinoscopieINTRODUCTION : CT-guided biopsies take today a increasing role for the diagnosis of mediastinal masses. Our purpose was to evaluate the efficacy and safety of CT-guided mediastinal biopsies in a large cohort of patients. METHOD AND MATERIALS : We retrospectively reviewed 308 consecutive CT-guided biopsies performed in our department between 2006 and 2011. For each procedure, we recorded the indication for biopsy, the size and location of the target, the size and type of biopsy needle, the appproach to the lesion, the number of biopsy samples, the complications, and the pathological diagnosis obtained. RESULTS AND DISCUSSION : In 254 patients (82,5%), CT- guided biopsy allowed to obtain a diagnosis and determine a diagnostic strategy. In 5 more percent, a diagnosis was obtained by another image-guided biopsy. Efficacity rate increased significatively with target lesion size. Complications, mainly bleedings, occurred in 23 of patients (7,4%). Only 3 patients remainded hospitalized overnight. No statistical relationship has been found between complications occurrence and target lesion characteristics, or biopsy technical parameters. Our efficacity and complication rates were similar to those published in anterior studies. CONCLUSION : CT-Guided mediastinal biopsy is a sage and efficient technique. It should be proposed as first-line tool prior to mediastinoscopy ofr thoracoscopy in case of equivocal mediastinal massST QUENTIN EN YVELINES-BU (782972101) / SudocSudocFranceF

Avantages du drainage percutané de collections à l aide d introducteur à bout mousse, sous contrôle scanographique

PARIS7-Xavier Bichat (751182101) / SudocSudocFranceF

Individual xenografts for personalized treatment of women with metastatic triple negative breast cancer

Aim: Triple negative breast cancer (TNBC) is the most severe subtype of breast cancer with poor prognosis even when treated at a localized stage. The treatment of metastatic TNBC is still challenging daily clinical practice, mainly because of the lack of targeted therapies. In the last years, a molecular sub-classification of TNBC has opened the way to personalized medicine for this type of severe cancer.Methods: In this study, we assessed the added value of combining molecular analyses with individual xenografts to personalize the treatment of resort for five women with metastatic TNBC. While a patient was receiving one or two lines of chemotherapy, the corresponding xenograft model was tested with different drugs or drug combinations, mainly based on transcriptomic analyses of the tumor and on theoretical activated canonical pathways.Results: On the basis of transcriptomic analyses and chemosensitivity data obtained from TNBC individual xenografts, we personalized the resort treatment for the five women in our study. In all cases, despite the fact that this resort treatment was a third-line or a fourth-line treatment, the time to progression was longer than that observed with previous lines of chemotherapy. When we explored the 19 chemotherapy regimens given to these women and their corresponding xenograft models, there was a strong correlation between ΔSUVmax (maximum standard uptake value) on positron emission tomography-computed tomography and the corresponding coefficients of inhibition obtained in mice.Conclusion: The combination of gene expression profiling and individual xenografts is a promising method and could be proposed as a personalized therapeutic resort for women with metastatic TNBCs

Management of superior vena cava syndrome in critically ill cancer patients

The purpose of this study is to describe the management and outcome of critically ill cancer patients with Superior Vena Cava Syndrome (SVCS)

A massive open online course to teach undergraduate medical students in oncology: keys of success

International audienceMassive Open Online Courses (MOOCs) are gaining popularity in education while classroom lectures are being deserted, especially after COVID-19 pandemic. Their added value in teaching undergraduate medical students remains to be confirmed.This study evaluated a MOOC devoted to undergraduate medical students in a blended oncology-teaching university program. It was the first to target undergraduate medical students in oncology at its beginning.Students were asked to participate in a survey before and after MOOC to explore interactions between their characteristics and final grades, 65% of the participating students belonged to the rich class. 70% of the students completed the MOOC. Grades distributions were similar before and after MOOC implementation, so MOOC doesn't alter overall results. In addition, there was a positive effect of the MOOC on median grades on the immediate test. The univariate and multivariate analysis showed that socioeconomic status and student's willingness to participate interacted significantly with final results. Particularly, students' motivation and satisfaction were associated with better results; Almost 70% of students asked for blended learning.E-learning is reliable to teach oncology to undergraduate medical students. The success is directly linked to students’ willingness to participate, and can be improved using blended methods including tutorials

Feasibility of Outpatient Transradial Prostatic Artery Embolization and Safety of a Shortened Deflation Protocol for Hemostasis

Background: to evaluate the safety and feasibility of a shorter time to hemostasis applied to outpatient transradial (TR) Prostatic Artery Embolization (PAE). Methods: a retrospective bi-institutional study was conducted between July 2018 and April 2022 on 300 patients treated by outpatient TR PAE. Indications included lower urinary tract symptoms, acute urinary retention, and hematuria. Mean patient height was 176 ± 6.3 (158–192) cm. The primary endpoint was safety of a 45 min deflation protocol for hemostasis. The secondary endpoint was the feasibility of PAE using TR access. Results: technical success was 98.7% (296/300). There was one failure due to patient height. Mean DAP/fluoroscopy times were 16,225 ± 12,126.3 (2959–81,608) μGy·m2/35 ± 14.7 (11–97) min, and mean time to discharge was 80 ± 6 (75–90) min. All access site and embolization-related adverse events were minor. Mild hematoma occurred in 10% (30/300), radial artery occlusion (RAO) in 10/300 (3.3%) cases, and history of smoking was a predictor for RAO. There was no major event. Conclusion: the safety of TR PAE using a 45 min time to hemostasis was confirmed, and TR PAE is feasible in most cases. Radial artery occlusion was still observed and may be favored by smoking