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Background The aim of this ancillary study of the SARAH trial is to compare health-related quality of life (HRQoL) in patients with locally advanced or inoperable hepatocellular carcinoma (HCC) treated with transarterial radioembolisation (TARE) or sorafenib. Methods This study included randomised patients who received either TARE or at least one dose of sorafenib with no major deviation in the protocol and who had at least one QoL follow-up assessment in addition to the baseline evaluation. QoL was assessed from the date of randomisation using the European Organisation for Research and Treatment of Cancer QLQ-C30 questionnaire, until disease progression or other reasons for stopping study participation. Data were analysed using linear mixed and time-dependent models. Results A total of 285 patients were included (122 and 163, in the TARE and sorafenib groups, respectively). Questionnaire completion rates were similar (77.5% versus 80.4%, in the TARE and sorafenib groups, respectively, p = 0.25). Longitudinal HRQoL analysis showed a significant treatment and time effects for fatigue and global health status, and significant treatment, time and treatment by time interaction effects for appetite loss, diarrhoea and social functioning. The median time to deterioration for the global health status was 3.9 months (95% confidence interval [CI] 3.7–4.3) versus 2.6 months (95% CI 2.0–3.0) in the TARE and sorafenib groups, respectively. Conclusions HRQoL was preserved longer with TARE than with sorafenib in locally advanced HCC. These data could be used to optimise management of patients with advanced or inoperable HCC.

Purpose For differentiating tumor from inflammation and normal tissues, fluorodeoxyglucose ([18F]FDG) dual time point PET could be helpful. Albeit [18F]FLT is more specific for tumors than [18F]FDG; we explored the role of dual time point [18F]FLT-PET for discriminating benign from malignant tissues. Methods Before any treatment, 85 womens with de novo unifocal breast cancer underwent three PET acquisitions at 33.94 ± 8.01 min (PET30), 61.45 ± 8.30 min (PET60), and 81.06 ± 12.12 min (PET80) after [18F]FLT injection. Semiquantitative analyses of [18F]FLT uptake (SUV) were carried out on tumors, liver, bone marrow (4th thoracic vertebra (T4) and humeral head), descending thoracic aorta, muscle (deltoid), and contralateral normal breast. Repeated measures ANOVA tests and Tukey’s posttests were used to compare SUVmax of each site at the three time points. Results There was a significant increase in SUVmax over time for breast lesions (5.58 ± 3.80; 5.97 ± 4.56; 6.19 ± 4.42; p < 0.0001) (m ± SD for PET30, PET60, and PET80, respectively), and bone marrow (for T4, 8.21 ± 3.17, 9.64 ± 3.66, 10.85 ± 3.63, p < 0.0001; for humeral head, 3.36 ± 1.79, 3.87 ± 1.89, 4.39 ± 2.00, p < 0.0001). A significant decrease in SUVmax over time was observed for liver (6.79 ± 2.03; 6.24 ± 1.99; 5.57 ± 1.74; p < 0.0001), muscle (0.95 ± 0.28; 0.93 ± 0.29; 0.86 ± 0.20; p < 0.027), and aorta (1.18 ± 0.34; 1.01 ± 0.32; 0.97 ± 0.30; p < 0.0001). No significant difference was observed for SUVmax in contralateral breast (0.8364 ± 0.40; 0.78 ± 0.38; 0.80 ± 0.35). Conclusion [18F]FLT-SUVmax increased between 30 and 80 min only in proliferating tissues. This could be helpful for discriminating between residual tumor and scar tissue.

Purpose For differentiating tumor from inflammation and normal tissues, fluorodeoxyglucose ([18F]FDG) dual time point PET could be helpful. Albeit [18F]FLT is more specific for tumors than [18F]FDG; we explored the role of dual time point [18F]FLT-PET for discriminating benign from malignant tissues. Methods Before any treatment, 85 womens with de novo unifocal breast cancer underwent three PET acquisitions at 33.94 ± 8.01 min (PET30), 61.45 ± 8.30 min (PET60), and 81.06 ± 12.12 min (PET80) after [18F]FLT injection. Semiquantitative analyses of [18F]FLT uptake (SUV) were carried out on tumors, liver, bone marrow (4th thoracic vertebra (T4) and humeral head), descending thoracic aorta, muscle (deltoid), and contralateral normal breast. Repeated measures ANOVA tests and Tukey’s posttests were used to compare SUVmax of each site at the three time points. Results There was a significant increase in SUVmax over time for breast lesions (5.58 ± 3.80; 5.97 ± 4.56; 6.19 ± 4.42; p < 0.0001) (m ± SD for PET30, PET60, and PET80, respectively), and bone marrow (for T4, 8.21 ± 3.17, 9.64 ± 3.66, 10.85 ± 3.63, p < 0.0001; for humeral head, 3.36 ± 1.79, 3.87 ± 1.89, 4.39 ± 2.00, p < 0.0001). A significant decrease in SUVmax over time was observed for liver (6.79 ± 2.03; 6.24 ± 1.99; 5.57 ± 1.74; p < 0.0001), muscle (0.95 ± 0.28; 0.93 ± 0.29; 0.86 ± 0.20; p < 0.027), and aorta (1.18 ± 0.34; 1.01 ± 0.32; 0.97 ± 0.30; p < 0.0001). No significant difference was observed for SUVmax in contralateral breast (0.8364 ± 0.40; 0.78 ± 0.38; 0.80 ± 0.35). Conclusion [18F]FLT-SUVmax increased between 30 and 80 min only in proliferating tissues. This could be helpful for discriminating between residual tumor and scar tissue.

International audience; Internal radiation strategies hold great promise for glioblastoma (GB) therapy. We previously developed a nanovectorized radiotherapy that consists of lipid nanocapsules loaded with a lipophilic complex of Rhenium-188 (LNC(188)Re-SSS). This approach resulted in an 83 % cure rate in the 9L rat glioma model, showing great promise. The efficacy of LNC(188)Re-SSS treatment was optimized through the induction of a T-cell immune response in this model, as it is highly immunogenic. However, this is not representative of the human situation where T-cell suppression is usually encountered in GB patients. Thus, in this study, we investigated the efficacy of LNC(188)Re-SSS in a human GB model implanted in T-cell deficient nude mice. We also analyzed the distribution and tissue retention of LNC(188)Re-SSS. We observed that intratumoral infusion of LNCs by CED led to their complete distribution throughout the tumor and peritumoral space without leakage into the contralateral hemisphere except when large volumes were used. Seventy percent of the (188)Re-SSS activity was present in the tumor region 24 h after LNC(188)Re-SSS injection and no toxicity was observed in the healthy brain. Double fractionated internal radiotherapy with LNC(188)Re-SSS triggered survival responses in the immunocompromised human GB model with a cure rate of 50 %, which was not observed with external radiotherapy. In conclusion, LNC(188)Re-SSS can induce long-term survival in an immunosuppressive environment, highlighting its potential for GB therapy.

Introduction La medecine nucleaire (MN) fait l’objet d’un critere dedie a l’organisation des secteurs d’activite a risque majeur (26.b) dans la certification V2014. Le 26 juillet 2016, l’Agence de surete nucleaire a publie une lettre circulaire rappelant ses « Recommandations concernant l’activite de manipulation des medicaments radiopharmaceutiques (MRP) et l’activite d’administration des MRP ». C’est dans ce contexte reglementaire que s’inscrit ce travail. L’objectif est d’ameliorer la qualite des soins en MN et d’elaborer un plan d’action de maitrise des risques suite notamment a la survenue de deux evenements indesirables en secteur cardiologie, au cours de l’annee 2016. Materiels et methode Un groupe de travail pluridisciplinaire medical et paramedical a ete constitue. La methode de l’analyse preliminaire des risques (APR) a ete choisie pour identifier et gerer les risques principaux a travers une vision globale du processus. Resultats Huit reunions pluridisciplinaires ont ete necessaires de janvier a aout 2017. Une analyse fonctionnelle du processus de « Realisation de la scintigraphie myocardique en secteur cardiologie » nous a permis de decouper celui-ci en 77 etapes. Une cartographie des dangers a ete etablie avec 4 dangers generiques : facteurs humains, management, realisation des soins et environnement. Trois cent onze situations dangereuses ont ete identifiees, pouvant entrainer 78 scenarios a risque dont 40 scenarios de criticite 2 (51 %) et 4 scenarios de criticite 3 (5 %). La fonction « Assurer la prise en charge du patient » ressort comme etant la plus critique. Les dangers generiques lies aux « Facteurs humains » et au « Management » sont les plus incrimines par les risques. Notre APR nous a permis d’elaborer un plan d’action avec 22 actions de maitrise des risques a mettre en place sur du court et moyen termes (21 actions preventives et 1 action de protection). Discussion et conclusion La methode de l’APR nous a permis de construire un travail pluridisciplinaire, complet et precis. Nous avons pu identifier et gerer les risques principaux a travers une vision globale du processus. Cette methode reste chronophage. La mise en place de mesures correctives est en cours. Pour maintenir la motivation du personnel nous devrons montrer l’efficacite des premieres actions en caracterisant les risques residuels.

Internal radiation strategies hold great promise for glioblastoma (GB) therapy. We previously developed a nanovectorized radiotherapy that consists of lipid nanocapsules loaded with a lipophilic complex of Rhenium-188 (LNC

Background This study is an assessment of the impact of acquisition times on SUV with [18F]FDG-PET/CT on healthy livers (reference organ with stable uptake over time) and on tumors. Methods One hundred six [18F]FDG-PET/CT were acquired in list mode over a single-bed position (livers (n = 48) or on tumors (n = 58)). Six independent datasets of different durations were reconstructed (from 1.5 to 10 min). SUVmax (hottest voxel), SUVpeak (maximum average SUV within a 1-cm3 spherical volume), and SUVaverage were measured within a 3-cm-diameter volume of interest (VOI) in the right lobe of the liver. For [18F]FDG avid tumors (SUVmax ≥ 5), the SUVmax, SUVpeak, and SUV41% (isocontour threshold method) were computed. Results For tumors, SUVpeak values did not vary with acquisition time. SUVmax displayed significant differences between 1.5- and 5–10-min reconstruction times. SUV41% was the most time-dependent parameter. For the liver, the SUVaverage was the sole parameter that did not vary over time. Conclusions For [18F]FDG avid tumors, with short acquisition times, i.e., with new generations of PET systems, the SUVpeak may be more robust than the SUVmax. The SUVaverage over a 3-cm-diameter VOI in the right lobe of the liver appears to be a good method for a robust and reproducible assessment of the hepatic metabolism.

Tests were performed on austenitic stainless steels. In order to investigate thermal fatigue resistance of quasi-structural specimens, test facilities enforcing temperature variations similar to those found under the operative conditions have been developed. Multiple cracking networks similar to those detected during in-service inspections have been reproduced. Experiments and simulations deal with crack initiation and crack growth. In the case of multiple cracking simulation, a Skelton's modelling has been used. A shielding effect between cracks is evidenced. It leads to a dramatic reduction of crack growth rate. Such effect is also crucial for the crack network stability under additional loading.

Objectif Actuellement, l’evaluation de la reponse therapeutique des DLBCL se fait a partir des criteres de Deauville (analyse visuelle). L’imagerie fonctionnelle permet une approche quantitative, a l’aide de differentes metriques semi-quantitatives telles que le standard uptake value (SUV) : les deltaSUVmax dans l’evaluation therapeutique des DLBC sont notamment en cours d’etude, le metabolic tumor volume (MTV) et le total lesion glycolysis (TLG = MTV × SUV moyen), ces deux dernieres metriques necessitent une segmentation du volume a l’aide d’une region d’interet. Il n’existe cependant aucun consensus pour definir ces parametres de seuillage. Nous avons donc evalue la faisabilite, la reproductibilite intra-observateur et la pertinence clinique de determiner des volumes metaboliques tumoraux (MTV) selon differentes methodes de seuillage dans les DLBCL. Methode Il s’agit d’une etude monocentrique retrospective sur 19 patients dont on a evalue les MTV initiaux (MTV0) et a 4 cures a partir de 4 seuillages : 1,4 × SUVmax hepatique(A), Iso25 % de la SUVmax(B),(1,5 × SUVmoy hepatique) + 2DS(C) et Iso41 % de la SUV max(D). L’analyse statistique a ete realisee a l’aide de graphiques de Bland et Altman, tests-t de Student sur donnees appariees et de courbes ROC a partir du logiciel XLSTAT. Resultats Le MTV0 median etait, respectivement, de 183,12 cm3(A), 178,23 cm3(B), 219,44 cm3(C) et 124,04 cm3(D). Le seuillage D (iso41 %) etait le seuillage le plus reproductible (moyenne des differences, 0,747) et le meilleur visuellement. En comparant les MTV et les deltaMTV (initial et 4 cures), seuillage D vs B : MTV0 differents (p = 0,0003) mais deltaMTV non different, A vs C : absence de difference des MTAV0 (p = 0,06) et des deltaMTV, C vs D : MTV0 differents (p = 0,003) et deltaMTV non different. Le seuil de MTV0 a 387,5 cm3 (seuillage D) est retenu comme meilleur seuil predictif du MTV0 sur la bonne reponse therapeutique a 4 cures (Se = 100 % et Sp = 87,5 % p = 0,0001). Discussion Quelle que soit la technique de seuillage utilisee, les volumes sont differents mais nous n’avons pas mis en evidence de difference significative de variation de volume entre le MTV0 et l’evaluation de la reponse therapeutique a 4 cures. Quel que soit le seuillage, les patients etaient donc bien classes en repondeur partiel ou complet (criteres de Deauville actuellement utilises). Enfin le seuillage iso41 % de la SUV max semble etre le meilleur tant visuellement que sur la reproductibilite intra-observateur.

International audience; ObjectifsLa tomographie par émission de positons (TEP) à la 16α-[18F]fluoro-17β-œstradiol ([18F]FES) permet d’évaluer in vivo la densité tissulaire en récepteurs aux œstrogènes (RE). Cet article rapporte les premiers cas dans le diagnostic de l’endométriose.Patientes et méthodesDans le cadre de la mise en place du PHRC ENDOTEP, quatre patientes présentant des signes cliniques et morphologiques (échographie pelvienne ± IRM) suspects d’endométriose ont bénéficié d’une TEP-[18F]FES avant cœlioscopie (analyse macroscopique et analyse histologique et immunohistochimique de l’expression en RE des lésions prélevées).RésultatsChez les quatre patientes, le diagnostic d’endométriose a été retenu macroscopiquement et après analyse histologique d’au moins une lésion. Aucune captation de [18F]FES par les lésions d’endométriose n’a été observée chez les trois premières patientes sous traitement œstroprogestatif. La quatrième patiente non traitée et en première partie de cycle menstruel lors de la réalisation de la TEP-[18F]FES présentait en revanche une hyperfixation d’une lésion d’endométriose confirmée en cœlioscopie.ConclusionNous rapportons le premier cas de fixation de [18F]FES par une lésion d’endométriose. À travers le projet ENDOTEP, les performances de la TEP-[18F]FES pour le diagnostic d’endométriose seront évaluées chez des patientes ne recevant pas de traitement hormonal.; ObjectifsLa tomographie par émission de positons (TEP) à la 16α-[18F]fluoro-17β-œstradiol ([18F]FES) permet d’évaluer in vivo la densité tissulaire en récepteurs aux œstrogènes (RE). Cet article rapporte les premiers cas dans le diagnostic de l’endométriose.Patientes et méthodesDans le cadre de la mise en place du PHRC ENDOTEP, quatre patientes présentant des signes cliniques et morphologiques (échographie pelvienne ± IRM) suspects d’endométriose ont bénéficié d’une TEP-[18F]FES avant cœlioscopie (analyse macroscopique et analyse histologique et immunohistochimique de l’expression en RE des lésions prélevées).RésultatsChez les quatre patientes, le diagnostic d’endométriose a été retenu macroscopiquement et après analyse histologique d’au moins une lésion. Aucune captation de [18F]FES par les lésions d’endométriose n’a été observée chez les trois premières patientes sous traitement œstroprogestatif. La quatrième patiente non traitée et en première partie de cycle menstruel lors de la réalisation de la TEP-[18F]FES présentait en revanche une hyperfixation d’une lésion d’endométriose confirmée en cœlioscopie.ConclusionNous rapportons le premier cas de fixation de [18F]FES par une lésion d’endométriose. À travers le projet ENDOTEP, les performances de la TEP-[18F]FES pour le diagnostic d’endométriose seront évaluées chez des patientes ne recevant pas de traitement hormonal.

International audience; The visualization of symmetric structure by [18F]-FluoroDeoxyGlucose-Positron Emission Tomography (FDG-PET), corresponding to adipose density in computed tomography (CT), has led to the idea that Brown Adipose Tissue (BAT) could be present in adult human.This article studies the FDG uptake in a mice model deficient on Uncoupling Protein 1 (UCP1), in a simple thermal activation protocol.Methods:FDG were injected in mice, control and knock out (K.O.) for the UCP1. Before imaging mice were placed either in cold or warm environment. BAT uptake was evaluated by ratio named RISC.Results:In warm condition, mean value of the Ratio of Inter-Scapular uptake (RISC) was 1.34 +/﹣0.27. After cold exposure, RISC increased 2 fold for control mice, male K.O. did not increase their RISC, female K.O. increased their RISC up to 2.45.Conclusion:Our study brought a further confirmation that FDG-PET visualised activated Brown Adipose Tissue. It gives a direct proof of the role of UCP1 in this process. The FDG uptake by cold female K.O.mice was unexpected.

International audience; UNLABELLED: A multi-centre trial using PET requires the analysis of images acquired on different systems We designed a multi-centre trial to estimate the value of 18F-FLT-PET to predict response to neoadjuvant chemotherapy in patients with newly diagnosed breast cancer. A calibration check of each PET-CT and of its peripheral devices was performed to evaluate the reliability of the results.MATERIAL AND METHODS: 11 centres were investigated. Dose calibrators were assessed by repeated measurements of a 68Ge certified source. The differences between the clocks associated with the dose calibrators and inherent to the PET systems were registered. The calibration of PET-CT was assessed with an homogeneous cylindrical phantom by comparing the activities per unit of volume calculated from the dose calibrator measurements with that measured on 15 Regions of Interest (ROIs) drawn on 15 consecutive slices of reconstructed filtered back-projection (FBP) images. Both repeatability of activity concentration based upon the 15 ROIs (ANOVA-test) and its accuracy were evaluated.RESULTS: There was no significant difference for dose calibrator measurements (median of difference -0.04%; min = -4.65%; max = +5.63%). Mismatches between the clocks were less than 2 min in all sites and thus did not require any correction, regarding the half life of 18F. For all the PET systems, ANOVA revealed no significant difference between the activity concentrations estimated from the 15 ROIs (median of difference -0.69%; min = -9.97%; max = +9.60%).CONCLUSION: No major difference between the 11 centres with respect to calibration and cross-calibration was observed. The reliability of our 18F-FLT multi-centre clinical trial was therefore confirmed from the physical point of view. This type of procedure may be useful for any clinical trial involving different PET systems.

International audience; Axillary lymph node and distant metastases are unfavourable prognostic factors in breast cancer. The aim of our study was to evaluate the performance of PET-FDG in the staging of locally advanced breast cancer (LABC) treated with neoadjuvant chemotherapy (NAC) and surgery, and to compare the findings of pretherapeutic PET to those of axillary nodal status obtained by surgery after NAC (Sataloff classification). This retrospective study involved 89 patients with LABC explored at presentation by PET in addition to conventional clinical and imaging staging (CS). Breast cancer excision and axillary dissection were performed after NAC. PET and CS found an axillary involvement in 58 patients (65%) and 39 patients (44%), respectively. Compared to the histology of post-NAC axillary dissection, PET had sensitivity and specificity of 80% and 63%, respectively. PET revealed an extra-axillary lymph node involvement, not suspected by the CS, in 25 patients (28%). Bone and lung metastases, not suspected by the CS were found in two and one patients, respectively. A case of false-positive PET in the liver was observed (adenomatosis). This study confirms the value of PET in the initial staging of LABC, especially in assessing extra-axillary nodal status. In the determination of axillary status, PET has a high positive predictive value, cases of doubtful interpretation suggesting to perform ultrasound-guided fine needle aspiration in addition.; L’atteinte ganglionnaire axillaire et la présence de métastases à distance sont des facteurs pronostiques majeurs dans la prise en charge du cancer du sein. L’objectif de notre travail a été d’évaluer les performances de la TEP-FDG dans le bilan initial de cancers du sein localement avancés (CSLA) traités par chimiothérapie néo-adjuvante (CNA) et chirurgie, et de comparer les données de la TEP préthérapeutique à celles de l’histologie du curage réalisé après CNA (classification de Sataloff). Cette étude rétrospective a concerné 89patientes porteuses d’un CSLA, explorées avant mise en route de la CNA par une TEP en complément du bilan d’extension standard (BS). Toutes les patientes ont bénéficié après CNA d’une tumorectomie/mastectomie et d’un curage axillaire. Une atteinte axillaire a été retrouvée chez 58patientes (65%) par la TEP et 39patientes (44%) par le BS. Comparées à l’histologie du curage axillaire post-CNA, les sensibilité et spécificité de la TEP ont été calculées à 80% et 63%. La TEP a révélé une atteinte ganglionnaire extra-axillaire, non suspectée par le BS, chez 25patientes (28%). Des lésions métastatiques méconnues par le BS ont été découvertes au niveau osseux chez deux patientes et pulmonaire chez une patiente. Un cas de faux-positif TEP hépatique a été observé (adénomatose). Cette étude confirme l’intérêt de la TEP dans le staging initial des CSLA, notamment au niveau ganglionnaire extra-axillaire. Au niveau axillaire, une TEP positive suggère fortement une atteinte métastatique; les cas d’interprétation douteuse incitant à réaliser en complément une cytoponction échoguidée.

International audience; The aim of this work was to develop a new microparticulate system able to form a complex with radionuclides with a high yield of purity for diagnostic or therapeutic applications. Owing to its properties potato starch was chosen as starting material and modified by oxidization and coupling of a ligand (polyamine) enabling modified starch to chelate radionuclides. The choice of suitable experiments was based on a combination of a Rechtschaffner experimental design and a surface response design to determine the influence of experimental parameters and to optimize the final product. Starch-based microparticle formulations from the experimental plans were compared and characterized through particle size analysis, scanning electron microscopy, elemental analysis and, for the most promising formulations, by in vitro labeling stability studies and determination of free polyamine content or in vivo imaging studies. The mechanism of starch-based microparticle degradation was identified by means of size measurements. The results of the Rechtschaffner design showed the positive qualitative effect of the temperature and the duration of coupling reaction whereas surface response analysis clearly showed that, by increasing the oxidization level and starch concentration, the nitrogen content in the final product is increased. In vitro and in vivo characterization led to identification of the best formulation. With a size around 30 mum, high radiochemical purity (over 95%) and a high signal-to-noise ratio (over 600), the new starch-based microparticulate system could be prepared as ready-to-use kits and sterilized without modification of its characteristics, and thus meet the requirement for in vivo diagnostic and therapeutic applications.

International audience; BACKGROUND: In 2008, American consensus recommendations for performing gastric emptying (GE) scintigraphy were published. It was recommended that data are acquired only at 0, 1, 2, and 4 h and that the results are expressed as percentages of meal retention. Until now, it was established that the GE time-activity curves should have many points (every 10, 15, or 20 min) to reflect the GE process accurately and to be optimally adjusted by a mathematical model. In this study, we have evaluated the curve fitting using only a few points as proposed by the consensus protocol. MATERIALS AND METHODS: GE scintigraphy tests of 224 patients were retrospectively analyzed. Two curve fittings were done for each patient, either using data acquired every 20 min or using data acquired every hour. A comparison of these two methods was made based on the values of the computed GE parameters. RESULTS: We observed strong correlations between the two methods (r=0.81-0.99, P

Vascular prosthesis infection is an uncommon but life-threatening complication. Its diagnosis is difficult to establish especially due to the low specificity of computed tomography (CT). The aim of this preliminary study was to compare the diagnostic value of positron emission tomography with18FDG (18FDG-PET) and 99mTc-HMPAO-labeled leukocytes scintigraphy in this indication. 18FDG-PET/CT and 99mTc-HMPAO-labeled leukocytes scintigraphy (planar at 6th and 24th hours after injection + SPECT/CT at the 6th hour) were prospectively performed in 11 patients (total of 22 vascular prosthesis with 14 clinical suspicions of infection). Both scans were retrospectively and blindly assessed by two independent nuclear medicine physicians. Interpretation was based on visual analysis. The gold standard was bacteriology findings or clinical follow-up greater than 6 months. Eight prostheses were considered as infected. PET found eight true-positive and one false-positive. Scintigraphy found eight true-positive and no false-positive. A focal or heterogeneous FDG-uptake higher or equal than hepatic uptake was considered as positive in PET. A focal prosthetic activity, stable or increased at the 24th hour was considered as positive in labeled leukocyte scintigraphy. SPECT/CT gave accurate anatomic localization and differentiated clearly infections of soft tissues from those of prostheses. 18FDG-PET could be performed in first-line in suspicion of vascular prosthesis infection. In litigious cases, a99mTc-HMPAO-labeled leukocytes scintigraphy in association with SPECT/CT could bring additional arguments for infection diagnosis., L’infection de prothèse vasculaire est une complication rare, mais grave. Son diagnostic est difficile, notamment car l’imagerie conventionnelle est peu spécifique. Le but de cette étude préliminaire était de comparer l’apport diagnostique de la tomographie par émission de positons au 18FDG (TEP-18FDG) à celui de la scintigraphie aux leucocytes marqués à l’HMPAO-99mTc dans cette indication. Réalisation prospective d’une TEP-18FDG couplée au scanner et d’une scintigraphie aux leucocytes marqués (planaires à la sixième et 24e heures+tomographie par émission monophotonique couplée à la tomodensitométrie [TEMP-TDM] à la sixième heure) chez 11patients (22prothèses au total avec suspicion clinique d’infection pour 14d’entre elles). Relecture rétrospective, en aveugle, des examens par deux médecins nucléaires. Interprétation basée sur une analyse visuelle de l’intensité et de l’aspect de la fixation des prothèses. L’étalon de référence était la bactériologie ou un suivi supérieur à six mois. L’infection de prothèse était retenue dans huit cas. La TEP retrouvait huit vrais positifs et un faux positif et la scintigraphie, huit vrais positifs et aucun faux positif. Une hyperfixation focale ou hétérogène supérieure ou égale à la fixation hépatique était retenue comme positive en TEP. Une hyperfixation focale stable ou augmentée à 24heures était retenue comme positive pour la scintigraphie. La TEMP-TDM a permis de localiser avec précision les infections limitées aux tissus mous. La TEP-18FDG pourrait être effectuée en première intention dans les suspicions d’infection de prothèses vasculaires et complétée, en cas de doute, par une scintigraphie aux leucocytes avec TEMP-TDM.

Receptor targeting with radiolabeled peptides has become very important in nuclear oncology in the past few years. The most frequently used peptides in the clinic are analogs of somatostatin. However, other radiolabeled analogs have also been developed and assessed in vitro and in vivo and some of them are already in clinical use. For instance, radiolabeled analogs of alpha-melanocyte-stimulating hormone (alpha-MSH), neurotensin, vasoactive intestinal peptide (VIP), bombesin (BN), substance P (SP), cholecystokinin (CCK), integrins… This review focuses on gallium-68radiolabeled peptides developed for PET imaging, except for somatostatin analogs, which are discussed in another article., Le ciblage de récepteurs avec des peptides radiomarqués est devenu très important en oncologie nucléaire au cours de ces dernières années. Les peptides les plus fréquemment utilisés en clinique sont les analogues de la somatostatine. Cependant, d’autres analogues radiomarqués ont également été développés et évalués in vitro et in vivo et pour certains déjà en clinique. Il s’agit par exemple de l’alpha-melanocyte-stimulating hormone (alpha-MSH), de la neurotensine, du peptide intestinal vasoactif (VIP), de la bombésine, de la substance P (SP) et de la cholécystokinine (CCK), des intégrines… Cette revue se focalise sur les peptides radiomarqués au gallium-68, développés pour l’imagerie TEP, en dehors des analogues de la somatostatine, qui sont discutés dans un autre article.

International audience; PURPOSE:In order to avoid the microbiological risks linked to human serum albumin macroaggregates (MAA) used for lung perfusion scintigraphy, we developed a new starch-based Tc-99m potential radiopharmaceutical.METHODS:Microparticles were prepared from oxidised starch coupled to natural polyamine for Tc-99m complexation. Suspensions were formulated as ready-to-use kits for easy one-step labelling procedures.RESULTS:Particle-size analysis, electron microscopy, and confocal microscopy were performed for microparticle characterisation, and gave a typical size distribution ranging from 7 to 63 microm, with a homogenous population of spherical or oval-shaped microparticles. Radiochemical purity exceeded 95%, and was stable for at least 8 h. When challenged with histidine and human plasma, labelling was also stable. Dynamic scintigraphic acquisitions and biodistribution studies conducted on healthy Wistar rats showed a tracer accumulation with more than 80% of the ID in the lungs after 15 min.CONCLUSIONS:With clinically significant characteristics such as a lung half-life of 3 h, a lung-to-vascular ratio of 900, and a lung-to-liver ratio of 90, starch-based microparticles exhibit all the qualities for an effective new lung perfusion agent.

International audience

International audience