0000000000072081
AUTHOR
Jean-marc Vrigneaud
Application of the optically stimulated luminescence (OSL) technique for mouse dosimetry in micro-CT imaging
International audience; Purpose: Micro-CT is considered to be a powerful tool to investigate various models of disease on anesthetized animals. In longitudinal studies, the radiation dose delivered by the micro-CT to the same animal is a major concern as it could potentially induce spurious effects in experimental results. Optically stimulated luminescence dosimeters (OSLDs) are a relatively new kind of detector used in radiation dosimetry for medical applications. The aim of this work was to assess the dose delivered by the CT component of a micro-SPECT (single-photon emission computed tomography)/CT camera during a typical whole-body mouse study, using commercially available OSLDs based o…
DOTAGA-Trastuzumab. A New Antibody Conjugate Targeting HER2/Neu Antigen for Diagnostic Purposes.
International audience; Improved bifunctional chelating agents (BFC) are required for indium-111 radiolabeling of monoclonal antibodies (mAbs) under mild conditions to yield stable, target-specific agents. 2,2',2″-(10-(2,6-Dioxotetrahydro-2H-pyran-3-yl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid (DOTAGA-anhydride) was evaluated for mAb conjugation and labeling with indium-111. The DOTA analogue was synthesized and conjugated to trastuzumab-which targets the HER2/neu receptor-in mild conditions (PBS pH 7.4, 25 °C, 30 min) and gave a mean degree of conjugation of 2.6 macrocycle per antibody. Labeling of this immunoconjugate with indium-111 was performed in 75% yield after 1 h a…
Initial performance evaluation of a preclinical PETscanner available as a clippable assembly in a sequential PET/MRI system
International audience
Implementation of routine sequential PET/MR of the rat heart in an in-line preclinical scanner
International audience
18F-FDG PET-Derived Tumor Blood Flow Changes After 1 Cycle of Neoadjuvant Chemotherapy Predicts Outcome in Triple-Negative Breast Cancer
International audience; Previous studies have suggested that early changes in blood flow (BF) in response to neoadjuvant chemotherapy and evaluated with 150-water are a surrogate biomarker of outcome in women with breast cancer. This study investigates, in the triple-negative breast cancer subtype, the prognostic relevance of tumor BF changes (Delta BF) in response to chemotherapy, assessed using a short dynamic F-18-FDG PET acquisition. Methods: Forty-six consecutive women with triple-negative breast cancer and an indication for neoadjuvant chemotherapy were prospectively included. Women benefited from a baseline F-18-FDG PET examination with a 2-min chest-centered dynamic acquisition, sta…
Validation of SiPM-based PET imaging for left ventricular volumes measurements in preclinical imaging: comparison with simultaneously-acquired cardiac magnetic resonance at 7T.
International audience
Multi-modal image fusion for small animal studies in in-line PET /3T MRI
Congrès sous l’égide de la Société Française de Génie Biologique et Médical (SFGBM).; National audience; In the framework of small animal multi-modal imaging, the current progression of the IMAPPI project is illustrated by the design of an in-line PET/MRI prototype, coupled to a dedicated multi-resolution registration method allowing the robust fusion of data coming from both modalities. The first results show a good alignment of the data from tumor imaging at the level of the abdomen.
Texture analysis of tumour metabolism and perfusion for newly diagnosed breast cancer using dynamic first-pass 18F-FDG PET/CT
International audience
MANOTA: a promising bifunctional chelating agent for copper-64 immunoPET
International audience; Improved bifunctional chelating agents (BFC) are required for copper-64 radiolabelling of monoclonal antibodies (mAbs) under mild conditions to yield stable, target-specific imaging agents. Four different bifunctional chelating agents (BFC) were evaluated for Fab (Fragment antigen binding) conjugation and radiolabelling with copper-64. Two DOTA- (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and two NOTA- (1,4,7-triazacyclononane-1,4,7-triacetic acid) derivatives bearing a p-benzyl-isothiocyanate group were conjugated to Fab-trastuzumab - which targets the HER2/neu receptor - and the average number of chelators attached ranged from 2.4 to 4.3 macrocycles …
Modular Assembly of Multimodal Imaging Agents through an Inverse Electron Demand Diels–Alder Reaction
International audience; The combination of two imaging probes on a same biomolecule gives access to targeted bimodal imaging agents that can provide more accurate diagnosis, complementary information, or that may be used in different applications, such as PET imaging and fluorescence imagingassisted surgery. In this study, we demonstrate that dichlorotetrazine, a small, commercially available compound, can be used as a modular platform to easily assemble various imaging probes. Doubly-labeled tetrazines can then be conjugated to a protein through a biorthogonal IEDDA reaction. A series of difunctionalized tetrazine compounds containing various chelating agents and fluorescent dyes was synth…
18F-Choline PET/CT and multiparametric MRI for the detection of local recurrence of prostate cancer initially treated by radiotherapy: comparison with systematic transperineal mapping biopsy
International audience
Phase 0/1 of Positron Emission Tomography (PET) imaging agent [18F]-ODS2004436 as a marker of EGFR mutation in patients with non-small cell lung cancer (NSCLC)
e24184Background: Multiple EGFR tyrosine kinase inhibitors (TKIs) are approved for treatment of NSCLC harboring EGFR activating mutations or secondary TKIs resistant mutation. We evaluate a new PET...
Integrated PET/MRI in preclinical studies State of the art
International audience; The exquisite tissue contrast of magnetic resonance imaging (MRI), the absence of ionising radiation and the opportunity to obtain new molecular and functional data have strengthened the enthusiasm for coupling MRI rather than computed tomography (CT) to positron emission tomography (PET). When reviewing the current literature one might be surprised by the almost unlimited diversity of what is placed under the name of PET/MRI in the articles. The magnetic field is varying from 0.3 Tesla (T) to 9.4 T, the size of the bore varies also from the wide bore of clinical scanners to volumes limited to a few tens of mL. Many preclinical studies are performed using separate PE…
Functionalization of theranostic AGuIX® nanoparticles for PET/MRI/optical imaging
International audience; A novel trifunctional imaging probe containing a chelator of radiometal for PET, a NIR heptamethine cyanine dye, and a bioconjugatable handle, has been grafted onto AGuIX® nanoparticles via a Michael addition reaction. The resulting functionalized nanoparticles have been fully characterized, radiolabelled with 64Cu, and evaluated in a mice TSA tumor model using multimodal (PET/MRI/optical) imaging.
Evaluation of breast tumor blood flow with dynamic first-pass 18F-FDG PET/CT: comparison with angiogenesis markers and prognostic factors
The purpose of this study was to prospectively evaluate the relationship between tumor blood flow and glucose metabolism as evaluated by dynamic first-pass (18)F-FDG PET and by proliferation and endothelial pathologic markers in the setting of newly diagnosed breast cancer.Forty patients were prospectively included. Biopsy samples of each tumor were used to assess the Ki67 index of proliferation and immunostaining for CD34 (a panendothelial cell marker) and CD105 (a proliferation-related endothelial cell marker). All patients underwent (18)F-FDG PET/CT at least 1 wk after sample biopsy and before any treatment. A dynamic 2-min acquisition was performed immediately after intravenous injectio…
Contribution of tumour blood-flow for prediction of response to neoadjuvant chemotherapy in breast cancer using 18F-FDG PET/CT
International audience
Influence of Software Tool and Methodological Aspects of Total Metabolic Tumor Volume Calculation on Baseline [18F]FDG PET to Predict Survival in Hodgkin Lymphoma
Aim To investigate the respective influence of software tool and total metabolic tumor volume (TMTV0) calculation method on prognostic stratification of baseline 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography ([18F]FDG-PET) in newly diagnosed Hodgkin lymphoma (HL). Methods 59 patients with newly diagnosed HL were retrospectively included. [18F]FDG-PET was performed before any treatment. Four sets of TMTV0 were calculated with Beth Israel (BI) software: based on an absolute threshold selecting voxel with standardized uptake value (SUV) >2.5 (TMTV02.5), applying a per-lesion threshold of 41% of the SUVmax (TMTV041) and using a per-patient adapted threshold based on SUVmax of the…