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1.
Cancer Res Commun ; 3(12): 2483-2496, 2023 12 07.
Article in English | MEDLINE | ID: mdl-38009896

ABSTRACT

Medulloblastoma is one of the most prevalent solid tumors found in children, occurring in the brain's posterior fossa. The standard treatment protocol involves maximal resection surgery followed by craniospinal irradiation and chemotherapy. Despite a long-term survival rate of 70%, wide disparities among patients have been observed. The identification of pertinent targets for both initial and recurrent medulloblastoma cases is imperative. Both primary and recurrent medulloblastoma are marked by their aggressive infiltration into surrounding brain tissue, robust angiogenesis, and resistance to radiotherapy. While the significant role of integrin-αvß3 in driving these characteristics has been extensively documented in glioblastoma, its impact in the context of medulloblastoma remains largely unexplored. Integrin-αvß3 was found to be expressed in a subset of patients with medulloblastoma. We investigated the role of integrin-αvß3 using medulloblastoma-derived cell lines with ß3-subunit depletion or overexpression both in vitro and in vivo settings. By generating radioresistant medulloblastoma cell lines, we uncovered an increased integrin-αvß3 expression, which correlated with increased susceptibility to pharmacologic integrin-αvß3 inhibition with cilengitide, a competitive ligand mimetic. Finally, we conducted single-photon emission computed tomography (SPECT)/MRI studies on orthotopic models using a radiolabeled integrin-αvß3 ligand (99mTc-RAFT-RGD). This innovative approach presents the potential for a novel predictive imaging technique in the realm of medulloblastoma. Altogether, our findings lay the foundation for employing SPECT/MRI to identify a specific subset of patients with medulloblastoma eligible for integrin-αvß3-directed therapies. This breakthrough offers a pathway toward more targeted and effective interventions in the treatment of medulloblastoma. SIGNIFICANCE: This study demonstrates integrin-αvß3's fundamental role in medulloblastoma tumorigenicity and radioresistance and the effect of its expression on cilengitide functional activity.


Subject(s)
Brain Neoplasms , Cerebellar Neoplasms , Medulloblastoma , Child , Humans , Brain Neoplasms/drug therapy , Cerebellar Neoplasms/drug therapy , Integrin alphaVbeta3/genetics , Ligands , Medulloblastoma/drug therapy , Tomography, Emission-Computed, Single-Photon/methods
2.
Cancers (Basel) ; 15(19)2023 Oct 03.
Article in English | MEDLINE | ID: mdl-37835533

ABSTRACT

The theranostic approach in oncology holds significant importance in personalized medicine and stands as an exciting field of molecular medicine. Significant achievements have been made in this field in recent decades, particularly in treating neuroendocrine tumors using 177-Lu-radiolabeled somatostatin analogs and, more recently, in addressing prostate cancer through prostate-specific-membrane-antigen targeted radionuclide therapy. The promising clinical results obtained in these indications paved the way for the further development of this approach. With the continuous discovery of new molecular players in tumorigenesis, the development of novel radiopharmaceuticals, and the potential combination of theranostics agents with immunotherapy, nuclear medicine is poised for significant advancements. The strategy of theranostics in oncology can be categorized into (1) repurposing nuclear medicine agents for other indications, (2) improving existing radiopharmaceuticals, and (3) developing new theranostics agents for tumor-specific antigens. In this review, we provide an overview of theranostic development and shed light on its potential integration into combined treatment strategies.

3.
EJNMMI Phys ; 10(1): 45, 2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37522931

ABSTRACT

PURPOSE: The main objective of this study was to evaluate the ability of a large field Cadmium Zinc Telluride (CZT) camera to estimate thyroid uptake (TU) on single photon emission computed tomography (SPECT) images with and without attenuation correction (Tomo-AC and Tomo-NoAC) compared with Planar acquisition in a series of 23 consecutive patients. The secondary objective was to determine radiation doses for the tracer administration and for the additional Computed Tomography (CT) scan. METHODS: Cross-calibration factors were determined using a thyroid phantom, for Planar, Tomo-AC and Tomo-NoAC images. Then Planar and SPECT/CT acquisitions centered on the thyroid were performed on 5 anthropomorphic phantoms with activity ranging from 0.4 to 10 MBq, and 23 patients after administration of 79.2 ± 3.7 MBq of [99mTc]-pertechnetate. We estimated the absolute thyroid activity (AThA) for the anthropomorphic phantoms and the TU for the patients. Radiation dose was also determined using International Commission on Radiological Protection (ICRP) reports and VirtualDoseTMCT software. RESULTS: Cross-calibration factors were 66.2 ± 4.9, 60.7 ± 0.7 and 26.5 ± 0.3 counts/(MBq s), respectively, for Planar, Tomo-AC and Tomo-NoAC images. Theoretical and estimated AThA for Planar, Tomo-AC and Tomo-NoAC images were statistically highly correlated (r < 0.99; P < 10-4) and the average of the relative percentage difference between theoretical and estimated AThA were (8.6 ± 17.8), (- 1.3 ± 5.2) and (12.8 ± 5.7) %, respectively. Comparisons between TU based on different pairs of images (Planar vs Tomo-AC, Planar vs Tomo-NoAC and Tomo-AC vs Tomo-NoAC) showed statistically significant correlation (r = 0.972, 0.961 and 0.935, respectively; P < 10-3). Effective and thyroid absorbed doses were, respectively (0.34CT + 0.95NM) mSv, and (3.88CT + 1.74NM) mGy. CONCLUSION: AThA estimation using Planar and SPECT/CT acquisitions on a new generation of CZT large-field cameras is feasible. In addition, TU on SPECT/CT was as accurate as conventional planar acquisition, but the CT induced additional thyroid exposure. Trial registration Name of the registry: Thyroid Uptake Quantification on a New Generation of Gamma Camera (QUANTHYC). TRIAL NUMBER: NCT05049551. Registered September 20, 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/record/NCT05049551?cntry=MC&draw=2&rank=4 .

4.
Eur J Emerg Med ; 29(6): 417-420, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-35762442

ABSTRACT

Chest CT-scan (CT) exceeds chest X-ray (CXR) to diagnose community-acquired pneumonia (CAP) but actual use and results remain unclear. We examine whether CT performed at ED visit improved ED diagnosis of CAP as compared to a final diagnosis of CAP at hospital discharge (gold standard diagnosis for the study), and how it impacts relevant clinical outcomes. This retrospective monocenter observational study was based on the analysis of the hospital database. Patients with a diagnosis of CAP in the ED (ICD-10 codes: J110, J111, from J12- to J18-, J440, J690, U0710, and U0711) were included. We compared ED patients who were diagnosed with CAP using CXR and CT. We measured diagnostic consistency, duration of ED visit, percentage of CXR and CT during hospital stay, hospital length-of-stay, ICU admission, and in-hospital mortality. Multivariate analysis was adjusted for CRB65 score by multiple logistic regression analysis for binary outcomes and by multivariate analysis of variance for continuous outcomes. We included 994 ED patients with an initial diagnosis of CAP (751 receiving CXR, 243 receiving CT). CT prescription in the ED increased over time ( P < 0.001). In patients admitted after ED, CT improved diagnosis consistency for CAP [88.2% vs. 80.9%; difference 7.3% (95% confidence interval 1.2-13.3%)] with a trend for lower hospital length-of-stay [10.2 vs. 12.2 days; difference -2.0 (95% confidence interval -3.9 to -0.1)], but not ICU admission ( P = 0.09) and in-hospital mortality ( P = 0.056). Diagnosis of patients admitted with CAP improved when CT was obtained at ED visit. These results should be reproduced at a larger scale to test whether early CT conserves healthcare resources.


Subject(s)
Community-Acquired Infections , Pneumonia , Humans , Retrospective Studies , Emergency Service, Hospital , Community-Acquired Infections/diagnostic imaging , Pneumonia/diagnostic imaging , Tomography, X-Ray Computed/methods
5.
Pharmaceutics ; 14(5)2022 May 13.
Article in English | MEDLINE | ID: mdl-35631639

ABSTRACT

Glioblastoma (GBM), the most common primary malignant brain tumor, is associated with a dismal prognosis. Standard therapies including maximal surgical resection, radiotherapy, and temozolomide chemotherapy remain poorly efficient. Improving GBM treatment modalities is, therefore, a paramount challenge for researchers and clinicians. GBMs exhibit the hallmark feature of aggressive invasion into the surrounding tissue. Among cell surface receptors involved in this process, members of the integrin family are known to be key actors of GBM invasion. Upregulation of integrins was reported in both tumor and stromal cells, making them a suitable target for innovative therapies targeting integrins in GBM patients, as their impairment disrupts tumor cell proliferation and invasive capacities. Among them, integrin-αvß3 expression correlates with high-grade GBM. Driven by a plethora of preclinical biological studies, antagonists of αvß3 rapidly became attractive therapeutic candidates to impair GBM tumorigenesis. In this perspective, the advent of nuclear medicine is currently one of the greatest components of the theranostic concept in both preclinical and clinical research fields. In this review, we provided an overview of αvß3 expression in GBM to emphasize the therapeutic agents developed. Advanced current and future developments in the theranostic field targeting αvß3 are finally discussed.

6.
Ther Adv Respir Dis ; 16: 17534666221096040, 2022.
Article in English | MEDLINE | ID: mdl-35485327

ABSTRACT

PURPOSE: We aimed to better understand the pathophysiology of SARS-CoV-2 pneumonia in non-critically ill hospitalized patients secondarily presenting with clinical deterioration and increase in oxygen requirement without any identified worsening factors. METHODS: We consecutively enrolled patients without clinical or biological evidence for superinfection, without left ventricular dysfunction and for whom a pulmonary embolism was discarded by computed tomography (CT) pulmonary angiography. We investigated lung ventilation and perfusion (LVP) by LVP scintigraphy, and, 24 h later, left and right ventricular function by Tc-99m-labeled albumin-gated blood-pool scintigraphy with late (60 mn) tomographic albumin images on the lungs to evaluate lung albumin retention that could indicate microvascular injuries with secondary edema. RESULTS: We included 20 patients with confirmed SARS-CoV-2 pneumonia. All had CT evidence of organizing pneumonia and normal left ventricular ejection fraction. No patient demonstrated preserved ventilation with perfusion defect (mismatch), which may discard a distal lung thrombosis. Patterns of ventilation and perfusion were heterogeneous in seven patients (35%) with healthy lung segments presenting a relative paradoxical hypoperfusion and hypoventilation compared with segments with organizing pneumonia presenting a relative enhancement in perfusion and preserved ventilation. Lung albumin retention in area of organizing pneumonia was observed in 12 patients (60%), indicating microvascular injuries, increase in vessel permeability, and secondary edema. CONCLUSION: In hospitalized non-critically ill patients without evidence of superinfection, pulmonary embolism, or cardiac dysfunction, various types of damage may contribute to clinical deterioration including microvascular injuries and secondary edema, inconsistencies in lung segments vascularization suggesting a dysregulation of the balance in perfusion between segments affected by COVID-19 and others. SUMMARY STATEMENT: Microvascular injuries and dysregulation of the balance in perfusion between segments affected by COVID-19 and others are present in non-critically ill patients without other known aggravating factors. KEY RESULTS: In non-critically ill patients without evidence of superinfection, pulmonary embolism, macroscopic distal thrombosis or cardiac dysfunction, various types of damage may contribute to clinical deterioration including 1/ microvascular injuries and secondary edema, 2/ inconsistencies in lung segments vascularization with hypervascularization of consolidated segments contrasting with hypoperfusion of not affected segments, suggesting a dysregulation of the balance in perfusion between segments affected by COVID-19 and others.


Subject(s)
COVID-19 , Clinical Deterioration , Heart Diseases , Pulmonary Embolism , Superinfection , Albumins , Critical Illness , Edema/diagnostic imaging , Edema/etiology , Humans , Lung/diagnostic imaging , Neovascularization, Pathologic , SARS-CoV-2 , Stroke Volume , Ventricular Function, Left
7.
Biochem Biophys Rep ; 27: 101098, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34430714

ABSTRACT

The chemokine receptors CXCR1/2 play a key role in the aggressiveness of several types of cancers including head and neck squamous cell carcinomas (HNSCCs). In HNSCCs, CXCR1/2 signaling promotes cell proliferation and angiogenesis leading to tumor growth and metastasis. The competitive inhibitor of CXCR1/2, C29, inhibits the growth of experimental HNSCCs in mice. However, a non-invasive tool to monitor treatment response is essential to implement the use of C29 in clinical practices. 18F-FDG PET/CT is a gold-standard tool for the staging and the post-therapy follow-up of HNSCCs patients. Our study aimed to perform the first in vivo monitoring of C29 efficacy by non-invasive 18F-FDG PET/CT imaging. Mice bearing experimental HNSCCs (CAL33) were injected with 18F-FDG (T0) and thereafter treated (n = 7 mice, 9 tumors, 50 mg/kg by gavage) or not (n = 7 mice, 10 tumors) with C29 for 4 consecutive days. Final 18F-FDG-tumor uptake was determined at day 4 (TF). The average relative change (TF-T0) in 18F-FDG tumor uptake was +25.85 ± 10.93 % in the control group vs -5.72 ± 10.07 % in the C29-treated group (p < 0.01). These results were consistent with the decrease of the tumor burden and with the decrease of tumor proliferating Ki67+ cells. These results paved the way for the use of 18F-FDG to monitor tumor response following C29 treatment.

8.
Int J Mol Sci ; 22(12)2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34203923

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC), accounting for 90-95% of all pancreatic tumors, is a highly devastating disease associated with poor prognosis. The lack of accurate diagnostic tests and failure of conventional therapies contribute to this pejorative issue. Over the last decade, the advent of theranostics in nuclear medicine has opened great opportunities for the diagnosis and treatment of several solid tumors. Several radiotracers dedicated to PDAC imaging or internal vectorized radiotherapy have been developed and some of them are currently under clinical consideration. The functional information provided by Positron Emission Tomography (PET) or Single Photon Emission Computed Tomography (SPECT) could indeed provide an additive diagnostic value and thus help in the selection of patients for targeted therapies. Moreover, the therapeutic potential of ß-- and α-emitter-radiolabeled agents could also overcome the resistance to conventional therapies. This review summarizes the current knowledge concerning the recent developments in the nuclear medicine field for the management of PDAC patients.


Subject(s)
Adenocarcinoma/pathology , Carcinoma, Pancreatic Ductal/pathology , Nuclear Medicine , Pancreatic Neoplasms/pathology , Adenocarcinoma/diagnosis , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/therapy , Animals , Carcinoma, Pancreatic Ductal/diagnosis , Carcinoma, Pancreatic Ductal/diagnostic imaging , Carcinoma, Pancreatic Ductal/therapy , Diagnostic Imaging , Humans , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/therapy , Radiopharmaceuticals/chemistry , Pancreatic Neoplasms
9.
Open Forum Infect Dis ; 8(4): ofab058, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33880387

ABSTRACT

The Dunning-Kruger premise assumes that unqualified people are unaware of their limited skills. We tested this hypothesis in the context of the coronavirus disease 2019 (COVID-19) pandemic. In this cross-sectional study, 2487 participants had to self-estimate their knowledge about COVID-19 in a questionnaire on the topic. Poor performers were more likely to use mass media and social networks as sources of information and had lower levels of education. The mean self-assessment (SD) was 6.88 (2.06) and was not linked to actual level of knowledge. This observation should prompt regulatory agencies and media to apply rules that limit dissemination of "infodemics" during global health crises.

10.
Clin Nucl Med ; 46(6): e317-e324, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33630808

ABSTRACT

PURPOSE: Physiological myocardial accumulation of FDG impairs the diagnosis of inflammatory/infectious or tumoral myocardial detection by FDG PET/CT. We prospectively evaluated the addition, 3 hours before imaging, of an intravenous 100-mL lipid emulsion infusion (Intralipid) to a high-fat, low-carbohydrate diet (HFLCD) for at least 2 meals followed by a fast of at least 6 to 12 hours in patients referred for the diagnosis of myocardial inflammation, endocarditis, cardiac or paracardiac masses, intracardiac device, or prosthetic valve infections. METHODS: Data of 58 patients consecutively included (28 Intralipid patients, 30 controls with HFLCD alone) were compared. FDG uptake in normal myocardium was scored from 0 (complete myocardial suppression) to 3 (high diffuse uptake). Myocardial maximal, peak, and mean SUV and the rate of interpretable images according to the clinical indication were measured. RESULTS: Compared with controls, Intralipid infusion significantly improved the rate of score 0 (89% vs 63%, P = 0.021), of interpretable images according to the clinical indication (100% vs 72%, P = 0.0047) and decreased all myocardial SUV values (eg, SUVmax median, 1.9 [interquartile range, 1.7-2.5] vs 3.1 [interquartile range, 2.3-4.1]; P < 0.001). CONCLUSIONS: A lipid emulsion infusion in addition to HFLCD better suppresses cardiac glucose metabolism than HFLCD alone.


Subject(s)
Fat Emulsions, Intravenous/pharmacology , Fluorodeoxyglucose F18 , Glucose/metabolism , Heart/drug effects , Heart/diagnostic imaging , Myocardium/metabolism , Positron Emission Tomography Computed Tomography , Adult , Biological Transport/drug effects , Female , Fluorodeoxyglucose F18/metabolism , Humans , Male , Middle Aged
12.
Eur J Nucl Med Mol Imaging ; 48(1): 260-268, 2021 01.
Article in English | MEDLINE | ID: mdl-32712702

ABSTRACT

PURPOSE: [18F]-2-Fluoro-2-deoxy-D-glucose PET/CT (FDG PET/CT) is a sensitive and quantitative technic for detecting inflammatory process. Glucose uptake is correlated with an increased anaerobic glycolysis seen in activated inflammatory cells such as monocytes, lymphocytes, and granulocytes. The aim of the study was to assess the inflammatory status at the presumed peak of the inflammatory phase in non-critically ill patients requiring admission for COVID-19. METHODS: Patients admitted with COVID-19 were prospectively enrolled. FDG PET/CT was performed from day 6 to day 14 of the onset of symptoms. Depending on FDG PET/CT findings, patients' profiles were classified as "inflammatory" or "low inflammatory." FDG PET/CT data were compared with chest CT evolution and short-term clinical outcome. All inflammatory sites were reported to screen potential extra-pulmonary tropism. RESULTS: Thirteen patients were included. Maximum standardized uptake values ranged from 4.7 to 16.3 in lungs. All patients demonstrated increased mediastinal lymph nodes glucose uptake. Three patients (23%) presented mild nasopharyngeal, two patients (15%) bone marrow, and five patients (38%) splenic mild increase in glucose uptake. No patient had significant digestive focal or segmental glucose uptake. There was no significant physiological myocardial glucose uptake in all patients except one. There was no correlation between PET lung inflammatory status and chest CT evolution or short-term clinical outcome. CONCLUSION: Inflammatory process at the presumed peak of the inflammatory phase in COVID-19 patients is obvious in FDG PET/CT scans. Glucose uptake is heterogeneous and typically focused on lungs. TRIAL REGISTRATION: NCT04441489. Registered 22 June 2020 (retrospectively registered).


Subject(s)
COVID-19/diagnostic imaging , Fluorodeoxyglucose F18 , Positron Emission Tomography Computed Tomography , Radiopharmaceuticals , Aged , Aged, 80 and over , COVID-19/classification , COVID-19/therapy , Female , Heart/diagnostic imaging , Humans , Inflammation/diagnostic imaging , Lung/diagnostic imaging , Lymph Nodes/diagnostic imaging , Male , Middle Aged , Treatment Outcome
13.
Radiology ; 286(1): 260-270, 2018 01.
Article in English | MEDLINE | ID: mdl-29040022

ABSTRACT

Purpose To compare the accuracy of a single 20-second deep-inspiration breath hold (DIBH) in fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) to that with conventional free-breathing (FB) whole-body PET/CT for the assessment, characterization, and quantification of lung lesions in terms of the blurring effect of respiratory motion. Materials and Methods Institutional review board approval was obtained, and the requirement to obtain informed consent was waived. A preclinical study was performed in a test population of 19 patients to evaluate the feasibility and consistency of DIBH techniques compared with phase-based respiratory gating (PBRG). One hundred fifteen patients with lung lesions were then prospectively included and assessed with FB PET/CT followed by 20-second DIBH PET/CT. Maximum standardized uptake value (SUVmax), peak standardized uptake value (SUVpeak), and number and size of nodules were reported for each acquisition and then compared with findings from histopathologic examination and/or clinical-radiologic follow-up. Statistical analysis was performed with the t test, χ2 test, Pearson correlation coefficient, and receiver operating characteristic analysis. Results In the test population, data obtained with DIBH PET and PBRG PET showed close correlation (r = 0.94, P < .001 for SUVmax and r = 0.98, P < .001 for SUVpeak). In the clinical population, both SUVmax and SUVpeak were significantly increased with DIBH compared with FB (5.60 ± 4.20 vs 3.11 ± 1.80 and 2.25 ± 1.75 vs 1.71 ± 0.96, respectively; P < .001). A significantly greater number of lung lesions was detected with DIBH PET/CT compared with FB PET/CT (P < .001), with the detection of 70 additional nodules and more accurate coregistration of 84. According to the area under the receiver operating characteristic curve for SUVpeak, DIBH demonstrated a higher level of accuracy than did FB (P = .039). Conclusion The DIBH PET/CT technique is feasible in routine clinical practice and is more sensitive for quantitative measurements and lesion localization. This technique reduces the blurring effect of respiratory motion, thus improving the diagnostic accuracy for lung nodules. © RSNA, 2017.


Subject(s)
Breath Holding , Image Interpretation, Computer-Assisted/methods , Lung Neoplasms/diagnostic imaging , Positron Emission Tomography Computed Tomography/methods , Adult , Aged , Feasibility Studies , Female , Humans , Male , Middle Aged , ROC Curve
14.
Radiat Oncol ; 9: 127, 2014 Jun 02.
Article in English | MEDLINE | ID: mdl-24885897

ABSTRACT

BACKGROUND: To assess the feasibility and benefit of integrating four-dimensional (4D) Positron Emission Tomography (PET) - computed tomography (CT) for liver stereotactic body radiation therapy (SBRT) planning. METHODS: 8 patients with 14 metastases were accrued in the study. They all underwent a non-gated PET and a 4D PET centered on the liver. The same CT scan was used for attenuation correction, registration, and considered the planning CT for SBRT planning. Six PET phases were reconstructed for each 4D PET. By applying an individualized threshold to the 4D PET, a Biological Internal Target Volume (BITV) was generated for each lesion. A gated Planning Target Volume (PTVg) was created by adding 3 mm to account for set-up margins. This volume was compared to a manual Planning Target Volume (PTV) delineated with the help of a semi-automatic Biological Target Volume (BTV) obtained from the non-gated exam. A 5 mm radial and a 10 mm craniocaudal margins were applied to account for tumor motion and set-up margins to create the PTV. RESULTS: One undiagnosed liver metastasis was discovered thanks to the 4D PET. The semi-automatic BTV were significantly smaller than the BITV (p = 0.0031). However, after applying adapted margins, 4D PET allowed a statistically significant decrease in the PTVg as compared to the PTV (p = 0.0052). CONCLUSIONS: In comparison to non-gated PET, 4D PET may better define the respiratory movements of liver targets and improve SBRT planning for liver metastases. Furthermore, non respiratory-gated PET exams can both misdiagnose liver metastases and underestimate the real internal target volumes.


Subject(s)
Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Neoplasms/pathology , Positron-Emission Tomography/methods , Radiosurgery , Radiotherapy Planning, Computer-Assisted , Respiratory-Gated Imaging Techniques/methods , Aged , Female , Follow-Up Studies , Humans , Imaging, Three-Dimensional , Liver Neoplasms/secondary , Male , Middle Aged , Neoplasm Staging , Neoplasms/therapy , Phantoms, Imaging , Pilot Projects , Prognosis , Prospective Studies , Radiotherapy Dosage , Radiotherapy, Intensity-Modulated , Tomography, X-Ray Computed , Tumor Burden
16.
Eur J Radiol ; 83(3): 509-15, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24332351

ABSTRACT

UNLABELLED: PET acquisition requires several minutes which can lead to respiratory motion blurring, to increase partial volume effect and SUV under-estimation. To avoid these artifacts, conventional 10-min phase-based respiratory gating (PBRG) can be performed but is time-consuming and difficult with a non-compliant patient. We evaluated an automatic amplitude-based gating method (AABG) which keeps 35% of the counts at the end of expiration to minimize respiratory motion. We estimated the impact of AABG on upper abdominal lesion detectability, quantification and patient management. METHODS: We consecutively included 31 patients (82 hepatic and 25 perihepatic known lesions). Each patient underwent 3 acquisitions on a Siemens Biograph mCT (4 rings and time-of-flight): a standard free-breathing whole-body (SWB, 5-7 steps/2.5 min per step, 3.3±0.4 MBq/kg of 18F-FDG), a 10-min PBRG with six bins and a 5-min AABG method. All gated acquisitions were performed with an ANZAI respiratory gating system. SUVmax and target to background ratio (TBR, defined as the maximum SUV of the lesion divided by the mean SUV of a region of interest drawn in healthy liver) were compared. RESULTS: All 94 lesions in SWB images were detected in the gated images. 10-min PBRG and 5-min AABG acquisitions respectively revealed 9 and 13 new lesions and relocated 7 and 8 lesions. Four lesions revealed by 5-min AABG were missed by 10-min PBRG in 3 non-compliant patients. Both gated methods failed to relocate 2 lesions seen on SWB acquisition. Compared to SWB, TBR increased significantly with 10-min PBRG and with 5-min AABG (respectively 41±59%, p=4.10-3 and 66±75%, p=6.10-5) whereas SUVmax did not (respectively 14±43%, p=0.29 with 10-min PBRG, and 24±46%, p=0.11 with 5-min AABG). CONCLUSION: The AABG is a fast and a user-friendly respiratory gating method to increase detectability and quantification of upper abdominal lesions compared to the conventional PBRG procedure and the SWB acquisition.


Subject(s)
Abdomen/diagnostic imaging , Abdominal Neoplasms/diagnostic imaging , Artifacts , Positron-Emission Tomography/methods , Radiographic Image Enhancement/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Respiratory-Gated Imaging Techniques/methods , Adolescent , Adult , Aged , Aged, 80 and over , Algorithms , Female , Fluorodeoxyglucose F18 , Humans , Male , Middle Aged , Motion , Radiopharmaceuticals , Reproducibility of Results , Sensitivity and Specificity , Young Adult
17.
Oncologist ; 18(2): 174-9, 2013.
Article in English | MEDLINE | ID: mdl-23335621

ABSTRACT

OBJECTIVES: Pelvic lymphadenectomy is associated with a significant risk of lower-limb lymphedema. In this proof-of-concept study, we evaluated the feasibility of identifying the lower-limb drainage nodes (LLDNs) during pelvic lymphadenectomy for endometrial cancer. Secondary objectives were to map lower-limb drainage and to assess the diagnostic value of our mapping technique. METHODS: This prospective study included patients with endometrial cancer requiring pelvic lymphadenectomy, without neoadjuvant radiotherapy or chemotherapy and without history of lower-limb surgery. A radiopharmaceutical was injected into both feet on the day before surgery. LLDNs were identified using preoperative lymphoscintigraphy and intraoperative isotopic probe detection, then removed before complete pelvic lymphadenectomy. LLDNs and pelvic lymphadenectomy specimens underwent separate histological analysis. RESULTS: Of the 12 patients with early-stage endometrial cancer, 10 underwent preoperative lymphoscintigraphy, which consistently identified inguinal, femoral, and pelvic LLDNs (detection rate: 100%). The intraoperative detection rate was 83% (10/12). Median number of hot nodes per patient was 5 nodes (range: 3-7) on the right and 3 nodes (range: 2-6) on the left. Of 107 LLDNs, 106 were in the external iliac area, including 38 in the lateral group and 45 in the intermediate and medial groups. None of the patients had node metastases at any site. No early complications related to the technique occurred. CONCLUSION: Our mapping technique appears feasible, safe, and associated with a high LLDN identification rate. LLDN mapping may allow the preservation of LLDNs, thereby decreasing the risk of lower-limb lymphedema and improving quality of life.


Subject(s)
Endometrial Neoplasms/surgery , Leg/blood supply , Lymph Node Excision/methods , Lymphedema/therapy , Aged , Endometrial Neoplasms/pathology , Female , Humans , Leg/anatomy & histology , Leg/pathology , Lymphedema/diagnosis , Lymphedema/pathology , Lymphedema/prevention & control , Middle Aged , Pelvis/surgery , Pilot Projects , Prospective Studies , Risk Factors , Tomography, Emission-Computed, Single-Photon
18.
Eur J Nucl Med Mol Imaging ; 39(3): 474-80, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22109667

ABSTRACT

PURPOSE: To evaluate the prognostic significance of increased mediastinal (18)F-FDG uptake in PET/CT for the staging of advanced ovarian cancer. METHODS: We retrospectively evaluated patients managed for FIGO stage III/IV ovarian cancer between 1 January 2006 and 1 June 2009. Patients were included if they had undergone (18)F-FDG PET/CT and surgery for initial staging. Exclusion criteria were age younger than 18 years, inability to undergo general anaesthesia, recurrent ovarian cancer, and borderline or nonepithelial malignancy. Whole-body PET/CT was performed after intravenous (18)F-FDG injection. The location of abnormal hot spots and (18)F-FDG maximal standard uptake values (SUV(max)) were recorded. We compared the complete cytoreduction and survival rates in groups defined based on mediastinal (18)F-FDG uptake and SUV(max) values. Kaplan-Meier curves of overall survival and disease-free survival were compared using the log-rank test. Hazard ratios with their 95% confidence intervals were computed. Adjusted hazard ratios were obtained using a multivariate Cox model. RESULTS: We included 53 patients, of whom 17 (32%) had increased mediastinal (18)F-FDG uptake. Complete cytoreduction was achieved in 14 (87.5%) of the 16 patients managed with primary surgery and in 21 (75%) of the 28 patients managed with interval surgery. Complete cytoreduction was achieved significantly more often among patients without increased mediastinal (18)F-FDG uptake (80.6% vs. 35.3%; p = 0.001). Disease-free survival was comparable between the two groups. By univariate analysis, overall mortality was significantly higher among patients with increased mediastinal (18)F-FDG uptake (hazard ratio 5.70, 95% confidence interval 1.74-18.6). The only factor significantly associated with overall survival by multivariate analysis was complete cytoreduction (adjusted hazard ratio 0.24, 95% confidence interval 0.07-0.89). CONCLUSION: Increased mediastinal (18)F-FDG uptake was common in patients with advanced ovarian cancer. However, complete cytoreduction, which was significantly more frequent among patients without mediastinal (18)F-FDG uptake, was the only factor independently associated with survival.


Subject(s)
Fluorodeoxyglucose F18/metabolism , Mediastinum , Multimodal Imaging , Ovarian Neoplasms/diagnostic imaging , Ovarian Neoplasms/pathology , Positron-Emission Tomography , Tomography, X-Ray Computed , Biological Transport , Female , Humans , Middle Aged , Neoplasm Staging , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/surgery , Prognosis , Retrospective Studies , Survival Analysis
19.
Stud Health Technol Inform ; 169: 135-9, 2011.
Article in English | MEDLINE | ID: mdl-21893729

ABSTRACT

This study addresses the question of communication between medical wards and the nuclear medicine department for the realization of myocardial perfusion scintigraphy. It analyses the effects of a reminder for completing the content of an order form. It shows that the CDSS impacted ordering practices. It could be seen as a system enabling to structure the information and improve the quality of orders.


Subject(s)
Decision Support Systems, Clinical/organization & administration , Medical Informatics/methods , Myocardial Perfusion Imaging/methods , Access to Information , Communication , Computer Communication Networks , Computer Graphics , Computers , Hospitals , Humans , Medical Record Linkage , Myocardial Perfusion Imaging/instrumentation , Perfusion , Software , Task Performance and Analysis
20.
J Nucl Med ; 52(7): 1048-55, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21680694

ABSTRACT

UNLABELLED: The aims of this cohort study were to evaluate initial tumor hypoxia in metastatic renal cell carcinoma (mRCC) and its changes after sunitinib treatment, using (18)F-fluoromisonidazole PET/CT, and investigate the possible prognostic value of initial tumor hypoxia or its changes under sunitinib therapy. METHODS: Antiangiogenic-naive patients with mRCC were prospectively enrolled in this cohort study. Before initiation of sunitinib, CT defined up to 10 targets that were assessed at 1 and 6 mo according to the response evaluation criteria in solid tumors (RECIST). Pretreatment target uptake of (18)F-fluoromisonidazole was compared with uptake at 1 mo. Targets were considered hypoxic when their maximal standard uptake value was above mean blood value + 2 SDs. Hypoxic volumes were also computed. Relationships between initial hypoxia status, initial degree of hypoxia, its change at 1 mo, and overall or progression-free survival (OS and PFS, respectively) were assessed by survival analysis. RESULTS: Fifty-three patients were included. Median follow-up was 16.8 mo. (18)F-fluoromisonidazole uptake significantly decreased in initially hypoxic target metastases but did not change in others (-22%, P < 10(-4), vs. +1.5%, P = 0.77; P = 10(-3) between groups). Seventy-five percent of patients with hypoxic metastases were free of progressive disease at 4.8 mo (95% confidence interval, 2.99-11.83), compared with 11.3 mo (95% confidence interval, 3.08-36.9) for other patients (P = 0.02), whereas OS was not significantly different. Changes in tumor hypoxia were not related to PFS or OS. CONCLUSION: Sunitinib reduced hypoxia in initially hypoxic RECIST target metastases but did not induce significant hypoxia in nonhypoxic RECIST target metastases. Patients with initially hypoxic targets have shorter PFS than others.


Subject(s)
Carcinoma, Renal Cell/drug therapy , Indoles/therapeutic use , Kidney Neoplasms/drug therapy , Misonidazole/analogs & derivatives , Positron-Emission Tomography , Pyrroles/therapeutic use , Tomography, X-Ray Computed , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma, Renal Cell/diagnostic imaging , Carcinoma, Renal Cell/pathology , Cell Hypoxia/drug effects , Cohort Studies , Disease Progression , Humans , Indoles/pharmacology , Kidney Neoplasms/diagnostic imaging , Kidney Neoplasms/pathology , Middle Aged , Neoplasm Metastasis , Prognosis , Pyrroles/pharmacology , Sunitinib , Survival Analysis , Time Factors , Treatment Outcome , Young Adult
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