• Clinical and Experimental Pediatrics
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• 제57권6호
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• pp.278-286
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• 2014

Purpose: To evaluate the potential utility of $^{123}I$-metaiodobenzylguanine ($^{123}I$-MIBG) scintigraphy and $^{18}F$-fluorodeoxyglucose ($^{18}F$-FDG) positron emission tomography (PET) for the detection of primary and metastatic lesions in pediatric neuroblastoma (NBL) patients, and to determine whether $^{18}F$-FDG PET is as beneficial as $^{123}I$-MIBG imaging. Methods: We selected 8 NBL patients with significant residual mass after operation and who had paired $^{123}I$-MIBG and $^{18}F$-FDG PET images that were obtained during the follow-up. We retrospectively reviewed the clinical charts and the findings of 45 paired scans. Results: Both scans correlated relatively well with the disease status as determined by standard imaging modalities during follow-up; the overall concordance rates were 32/45 (71.1%) for primary tumor sites and 33/45 (73.3%) for bone-bone marrow (BM) metastatic sites. In detecting primary tumor sites, $^{123}I$-MIBG might be superior to $^{18}F$-FDG PET. The sensitivity of $^{123}I$-MIBG and $^{18}F$-FDG PET were 96.7% and 70.9%, respectively, and their specificity were 85.7% and 92.8%, respectively. $^{18}F$-FDG PET failed to detect 9 true NBL lesions in 45 follow-up scans (false negative rate, 29%) with positive $^{123}I$-MIBG. For bone-BM metastatic sites, the sensitivity of $^{123}I$-MIBG and $^{18}F$-FDG PET were 72.7% and 81.8%, respectively, and the specificity were 79.1% and 100%, respectively. $^{123}I$-MIBG scan showed higher false positivity (20.8%) than $^{18}F$-FDG PET (0%). Conclusion: $^{123}I$-MIBG is superior for delineating primary tumor sites, and $^{18}F$-FDG PET could aid in discriminating inconclusive findings on bony metastatic NBL. Both scans can be complementarily used to clearly determine discrepancies or inconclusive findings on primary or bone-BM metastatic NBL during follow-up.

• International Journal of Stem Cells
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• 제16권4호
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• pp.363-375
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• 2023

Stem cells are the foundational cells for every organ and tissue in our body. Cell-based therapeutics using stem cells in regenerative medicine have received attracting attention as a possible treatment for various diseases caused by congenital defects. Stem cells such as induced pluripotent stem cells (iPSCs) as well as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), and neuroprogenitors stem cells (NSCs) have recently been studied in various ways as a cell-based therapeutic agent. When various stem cells are transplanted into a living body, they can differentiate and perform complex functions. For stem cell transplantation, it is essential to determine the suitability of the stem cell-based treatment by evaluating the origin of stem, the route of administration, in vivo bio-distribution, transplanted cell survival, function, and mobility. Currently, these various stem cells are being imaged in vivo through various molecular imaging methods. Various imaging modalities such as optical imaging, magnetic resonance imaging (MRI), ultrasound (US), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) have been introduced for the application of various stem cell imaging. In this review, we discuss the principles and recent advances of in vivo molecular imaging for application of stem cell research.

• Nuclear Medicine and Molecular Imaging
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• 제42권2호
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• pp.137-144
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• 2008

Positron emission tomography-computed tomography (PET/CT) provides both functional and anatomical images of high quality non-invasively with better precision in localization than PET alone. Increase in the use of PET/CT, coupled with increasing concerns about the quality of medical services accrued the demands for accurate evaluation of system performance and quality assurance. Thus, well designed programs for performance evaluation and quality assurance are needed. Widely used protocols for performance evaluation of PET are the methods proposed by National Electrical Manufacturers Association (NEMA) in 1994 and 2001. In addition, in order to maintain high quality of PET/CT images, quality assurance programs including periodic (daily, monthly, and yearly). Therefore, in this article, the methods and present state of performance evaluation and quality assurance of PET/CT are reviewed.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5599-5605
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• 2015

In oncology various imaging modalities play a crucial role in diagnosis, staging, restaging, treatment monitoring and follow up of various cancers. Stand-alone morphological imaging like computerized tomography (CT) and magnetic resonance imaging (MRI) provide a high magnitude of anatomical details about the tumor but are relatively dumb about tumor physiology. Stand-alone functional imaging like positron emission tomography (PET) and single photon emission tomography (SPECT) are rich in functional information but provide little insight into tumor morphology. Introduction of first hybrid modality PET/CT is the one of the most successful stories of current century which has revolutionized patient care in oncology due to its high diagnostic accuracy. Spurred on by this success, more hybrid imaging modalities like SPECT/CT and PET/MR were introduced. It is the time to explore the potential applications of the existing hybrid modalities, developing and implementing standardized imaging protocols and train users in nuclear medicine and radiology. In this review we discuss three existing hybrid modalities with emphasis on their technical aspects and clinical applications in oncology.

• Nuclear Medicine and Molecular Imaging
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• 제41권2호
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• pp.97-101
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• 2007

Correct localization of epileptogenic zone is important for the successful epilepsy surgery. Both ictal perfusion single photon emission computed tomography (SPECT) and interictal F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) can provide useful information in the presurgical localization of intractable partial epilepsy. These imaging modalities have excellent diagnostic sensitivity in medial temporal lobe epilepsy and provide good presurgical information in neocortical epilepsy. Also provide functional information about cellular functions to better understand the neurobiology of epilepsy and to better define the ictal onset zone, symptomatogenic zone, propagation pathways, functional deficit zone and surround inhibition zones. Multimodality imaging and developments in analysis methods of ictal perfusion SPECT and new PET ligand other than FDG help to better define the localization.

• Radiation Oncology Journal
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• 제36권2호
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• pp.95-102
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• 2018

Purpose: To evaluate the prognostic value of $^{18}F$-fluorodeoxyglucose positron-emission tomography (FDG PET) with computed tomography (CT) before and during radiotherapy (RT) in patients with head and neck cancer. Methods: Twenty patients with primary head and neck squamous cell carcinoma were enrolled in this study, of whom 6 had oropharyngeal cancer, 10 had hypopharyngeal cancer, and 4 had laryngeal cancer. Fifteen patients received concurrent cisplatin and 2 received concurrent cetuximab chemotherapy. FDG PET/CT was performed before RT and in the 4th week of RT. The parameters of maximum standardized uptake value, metabolic tumor volume, and total lesion glycolysis (TLG) of the primary tumor were measured, and the prognostic significance of each was analyzed with the Cox proportional hazards model. Results: Higher TLG (>19.0) on FDG PET/CT during RT was a poor prognostic factor for overall survival (OS) (p = 0.001) and progression-free survival (PFS) (p = 0.007). In the multivariate analysis, TLG during RT as a continuous variable was significantly associated with OS and PFS rate (p = 0.023 and p = 0.016, respectively). Tumor response worse than partial remission at 1 month after RT was another independent prognostic factor for PFS (p = 0.024). Conclusions: Higher TLG of the primary tumor on FDG PET/CT during RT was a poor prognostic factor for OS and PFS in patients with head and neck cancer.

• Radiation Oncology Journal
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• 제37권1호
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• pp.30-36
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• 2019

Purpose: This study aimed to identify the feasibility of the maximum standardized uptake value (SUVmax) on baseline 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) as a predictive factor for prognosis in early stage primary lung cancer treated with stereotactic body radiotherapy (SBRT). Materials and Methods: Twenty-seven T1-3N0M0 primary lung cancer patients treated with curative SBRT between 2010 and 2018 were retrospectively evaluated. Four patients (14.8%) treated with SBRT to address residual tumor after wedge resection and one patient (3.7%) with local recurrence after resection were included. The SUVmax at baseline PET/CT was assessed to determine its relationship with prognosis after SBRT. Patients were divided into two groups based on maximum SUVmax on pre-treatment FDG PET/CT, estimated by receiver operating characteristic curve. Results: The median follow-up period was 17.7 months (range, 2.3 to 60.0 months). The actuarial 2-year local control, progression-free survival (PFS), and overall survival were 80.4%, 66.0%, and 78.2%, respectively. With regard to failure patterns, 5 patients exhibited local failure (in-field failure, 18.5%), 1 (3.7%) experienced regional nodal relapse, and other 2 (7.4%) developed distant failure. SUVmax was significantly correlated with progression (p = 0.08, optimal cut-off point SUVmax > 5.1). PFS was significantly influenced by pretreatment SUVmax (SUVmax > 5.1 vs. SUVmax ≤ 5.1; p = 0.012) and T stage (T1 vs. T2-3; p = 0.012). Conclusion: SUVmax at pre-treatment FDG PET/CT demonstrated a predictive value for PFS after SBRT for lung cancer.

• Radiation Oncology Journal
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• 제31권3호
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• pp.111-117
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• 2013

Purpose: To determine whether the maximum standardized uptake value (SUV) of [$^{18}F$] fluorodeoxyglucose uptake by positron emission tomography (FDG PET) ratio of lymph node to primary tumor (mSUVR) could be a prognostic factor for node positive non-small cell lung cancer (NSCLC) patients treated with definitive radiotherapy (RT). Materials and Methods: A total of 68 NSCLC T1-4, N1-3, M0 patients underwent FDG PET before RT. Optimal cutoff values of mSUVR were chosen based on overall survival (OS). Independent prognosticators were identified by Cox regression analysis. Results: The most significant cutoff value for mSUVR was 0.9 with respect to OS. Two-year OS was 17% for patients with mSUVR > 0.9 and 49% for those with mSUVR ${\leq}0.9$ (p = 0.01). In a multivariate analysis, including age, performance status, stage, use of chemotherapy, and mSUVR, only performance status (p = 0.05) and mSUVR > 0.9 (p = 0.05) were significant predictors of OS. Two-year OS for patients with both good performance (Eastern Cooperative Oncology Group [ECOG] ${\leq}1$) and mSUVR ${\leq}0.9$ was significantly better than that for patients with either poor performance (ECOG > 1) or mSUVR > 0.9, 23% (71% vs. 23%, p = 0.04). Conclusion: Our results suggested that the mSUVR was a strong prognostic factor among patients with lymph node positive NSCLC following RT. Addition of mSUVR to performance status identifies a subgroup at highest risk for death after RT.

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2215-2217
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• 2015

Background: This systemic analysis was conducted to to evaluate the application value of positron emission tomography/computed tomography (PET/CT) in early diagnosis of lung cancer. Methods: Clinical studies evaluating the application value of PET/CT for patients underwent PET/CT imaging. The histological diagnosis served as the standard of truth. Results: Four clinical studies which including 1330 patients with pulmonary spaceoccupying lesions were considered eligible for inclusion. Systemic analysis suggested that, in all 1330 patients, pooled sensitivity was 98.7% (1313.2/1330) and specificity was 58.2%(276.85/476). Conclusion: This systemic analysis suggests that integrated PET/CT imaging provides high sensitivity, and reasonably high specificity, and could be applied for early diagnosis of lung cancer.

• Toxicological Research
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• 제29권1호
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• pp.1-6
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• 2013

The process of drug discovery and development requires substantial resources and time. The drug industry has tried to reduce costs by conducting appropriate animal studies together with molecular biological and genetic analyses. Basic science research has been limited to in vitro studies of cellular processes and ex vivo tissue examination using suitable animal models of disease. However, in the past two decades new technologies have been developed that permit the imaging of live animals using radiotracer emission, X-rays, magnetic resonance signals, fluorescence, and bioluminescence. The main objective of this review is to provide an overview of small animal molecular imaging, with a focus on nuclear imaging (single photon emission computed tomography and positron emission tomography). These technologies permit visualization of toxicodynamics as well as toxicity to specific organs by directly monitoring drug accumulation and assessing physiological and/or molecular alterations. Nuclear imaging technology has great potential for improving the efficiency of the drug development process.