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Paul B Shyn - One of the best experts on this subject based on the ideXlab platform.
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Liver Tumor f 18 fdg pet before and immediately after microwave ablation enables imaging and quantification of Tumor tissue contraction
European Journal of Nuclear Medicine and Molecular Imaging, 2021Co-Authors: Zihao Yan, Paul B Shyn, Ramin Khorasani, Vincent M. Levesque, Victor H. GerbaudoAbstract:Poor Liver Tumor visibility after microwave ablation (MWA) limits direct Tumor ablation margin assessments using contrast-enhanced CT or ultrasound (US). Positron emission tomography (PET) or PET/CT may offer improved intraprocedural assessment of Liver Tumor ablation margins versus current imaging techniques, as 18F-fluorodeoxyglucose (18F-FDG)-avid Tumors remain visible on PET immediately following ablation. The purpose of this study was to assess intraprocedural 18F-FDG PET scans before and immediately after PET/CT-guided MWA for visualization and quantification of metabolic Liver Tumor tissue contraction resulting from MWA. This retrospective study, conducted at a large academic medical center after Institutional Review Board approval, included 36 patients (20 men; mean age 63 [range 37–85]) who underwent PET/CT-guided MWA of 42 18F-FDG-avid Liver Tumors from May 2013 to March 2018. Tumor metabolic diameters (short/long axes) were measured for each Tumor on pre- and post-ablation PET images. Tumor metabolic volumes were calculated using Tumor diameter measurements and compared with automated volumes using an SUV threshold algorithm. A two-tailed paired t test was used for the analyses. Comparing intraprocedural pre- and post-ablation PET images, mean metabolic Tumor short- and long-axis diameters decreased from 21.4 to 14.9 mm [− 29%, p < 0.001, standard deviation (SD) 18%] and from 24.0 to 18.0 mm (− 24%, p < 0.001, SD 16%), respectively. The mean calculated Tumor metabolic volume decreased from 10.5 to 4.6 mm3 (− 55%, p < 0.001, SD 26%). The mean automated Tumor metabolic volume decreased from 10.6 to 5.8 mm3 (− 45%, p < 0.001, SD 30%). Intraprocedural PET images of 18F-FDG-avid Liver Tumors allow visualization and quantification of MWA-induced metabolic Tumor tissue contraction during 18F-FDG PET/CT-guided procedures. The ability to visualize contracted Tumor immediately post-MWA may facilitate emerging intraprocedural PET and PET/CT imaging techniques that address a clinical gap in directly assessing the ablation margin.
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f 18 fdg perfusion pet intraprocedural assessment of the Liver Tumor ablation margin
Abdominal Radiology, 2021Co-Authors: Paul B Shyn, Alan J Cubre, Paul J Catalano, Leslie K Lee, Hyewon Hyun, Kemal TuncaliAbstract:To evaluate 18F-fluorodeoxyglucose (FDG) perfusion PET during FDG PET/CT-guided Liver Tumor microwave ablation procedures for assessing the ablation margin and correlating minimum margin measurements with local progression. This IRB-approved, HIPAA-compliant study included 20 adult patients (11 M, 9 F; mean age 65) undergoing FDG PET/CT-guided Liver microwave ablation to treat 31 FDG-avid Tumors. Intraprocedural FDG perfusion PET was performed to assess the ablation margin. Intraprocedural decisions regarding overlapping ablations were recorded. Two readers retrospectively interpreted intraprocedural perfusion PET and postprocedural contrast-enhanced MRI. Assessability of the ablation margin and minimum margin measurements were recorded. Imaging follow-up for local progression ranged from 30 to 574 days (mean 310). Regression modeling of minimum margin measurements was performed. Hazard ratios were calculated to correlate an ablation margin threshold of 5 mm with outcomes. Intraprocedural perfusion PET prompted additional overlapping ablations of two Tumors, neither of which progressed. Incomplete ablation or local progression occurred in 8/31 (26%) Tumors. With repeat ablation, secondary efficacy was 26 (84%) of 31. Both study readers deemed ablation margins fully assessable more often using perfusion PET than MRI (OR 69.7; CI 6.0, 806.6; p = 0.001). Minimum ablation margins ≥ 5 mm on perfusion PET correlated with a low risk of incomplete ablation/local progression by both study readers (HR 0.08 and 0.02, p < 0.001). Intraprocedural FDG perfusion PET consistently enabled complete Liver Tumor microwave ablation margin assessments, and the perfusion PET minimum ablation margin measurements correlated well with local outcomes. Clinical trial registration clinicaltrials.gov (NCT02018107).
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Liver Tumor F-18 FDG-PET before and immediately after microwave ablation enables imaging and quantification of Tumor tissue contraction
European Journal of Nuclear Medicine and Molecular Imaging, 2020Co-Authors: Zihao Yan, Ramin Khorasani, Vincent M. Levesque, Victor H. Gerbaudo, Paul B ShynAbstract:Purpose Poor Liver Tumor visibility after microwave ablation (MWA) limits direct Tumor ablation margin assessments using contrast-enhanced CT or ultrasound (US). Positron emission tomography (PET) or PET/CT may offer improved intraprocedural assessment of Liver Tumor ablation margins versus current imaging techniques, as ^18F-fluorodeoxyglucose (^18F-FDG)-avid Tumors remain visible on PET immediately following ablation. The purpose of this study was to assess intraprocedural ^18F-FDG PET scans before and immediately after PET/CT-guided MWA for visualization and quantification of metabolic Liver Tumor tissue contraction resulting from MWA. Methods This retrospective study, conducted at a large academic medical center after Institutional Review Board approval, included 36 patients (20 men; mean age 63 [range 37–85]) who underwent PET/CT-guided MWA of 42 ^18F-FDG-avid Liver Tumors from May 2013 to March 2018. Tumor metabolic diameters (short/long axes) were measured for each Tumor on pre- and post-ablation PET images. Tumor metabolic volumes were calculated using Tumor diameter measurements and compared with automated volumes using an SUV threshold algorithm. A two-tailed paired t test was used for the analyses. Results Comparing intraprocedural pre- and post-ablation PET images, mean metabolic Tumor short- and long-axis diameters decreased from 21.4 to 14.9 mm [− 29%, p < 0.001, standard deviation (SD) 18%] and from 24.0 to 18.0 mm (− 24%, p < 0.001, SD 16%), respectively. The mean calculated Tumor metabolic volume decreased from 10.5 to 4.6 mm^3 (− 55%, p < 0.001, SD 26%). The mean automated Tumor metabolic volume decreased from 10.6 to 5.8 mm^3 (− 45%, p < 0.001, SD 30%). Conclusion Intraprocedural PET images of ^18F-FDG-avid Liver Tumors allow visualization and quantification of MWA-induced metabolic Tumor tissue contraction during ^18F-FDG PET/CT-guided procedures. The ability to visualize contracted Tumor immediately post-MWA may facilitate emerging intraprocedural PET and PET/CT imaging techniques that address a clinical gap in directly assessing the ablation margin.
Chang Chun Ling - One of the best experts on this subject based on the ideXlab platform.
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cxcl10 cxcr3 signaling mobilized regulatory t cells promote Liver Tumor recurrence after transplantation
Journal of Hepatology, 2016Co-Authors: Chang Chun Ling, Yan Shao, Hui Liu, Xiao Bing Liu, Yuen Yuen, Jiang Liu, Oscar W H Yeung, Xin Xiang YangAbstract:Background & Aims Liver graft injury and Tumor recurrence are the major challenges of Liver transplantation for the patients with hepatocellular carcinoma (HCC). Here, we aimed to explore the role and mechanism of Liver graft injury mobilizing regulatory T cells (Tregs), which lead to late phase Tumor recurrence after Liver transplantation. Methods The correlation among Tumor recurrence, Liver graft injury and Tregs mobilization were studied in 257 Liver transplant recipients with HCC and orthotopic rat Liver transplantation models. The direct roles of CXCL10/CXCR3 signaling on Tregs mobilization and Tumor recurrence were investigated in CXCL10 −/− and CXCR3 −/− mice models with hepatic IR injury. Results Clinically, patients received the graft with graft weight ratio (GWR) + cells and expressions of TLR4, CXCL10, TGFβ, CTLA-4 and CD274 were increased in rat Liver Tumor tissues from small-for-size graft group. In mouse model, the mobilization and recruitment of Tregs were decreased in TLR4 −/− , CXCL10 −/− and CXCR3 −/− mice compared to wild-type mice. Moreover, less CXCR3 + Tregs were recruited into Liver in CXCL10 −/− mice after hepatic IR injury. The knockout of CXCL10 and depletion of Tregs inhibited Tumor recurrence after hepatic IR injury. Conclusion CXCL10/CXCR3 signaling upregulated at Liver graft injury directly induced the mobilization and intragraft recruitment of Tregs, which further promoted HCC recurrence after transplantation. Lay summary There were positive correlation among Tumor recurrence, circulating Tregs and Liver graft injury after human transplantation for HCC patients. The knockout of CXCL10 decreased hepatic recruitment of CXCR3 + Tregs and late phase Tumor recurrence after hepatic IR injury.
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post transplant endothelial progenitor cell mobilization via cxcl10 cxcr3 signaling promotes Liver Tumor growth
Journal of Hepatology, 2014Co-Authors: Chang Chun Ling, Yan Shao, Wei Geng, Jiangwei Xiao, Hui Liu, Xiao Bing Liu, Yuen Yuen, Waiho Yeung, Nathalie Wong, Yuan ZhaiAbstract:Background & Aims Patients with hepatocellular carcinoma (HCC) receiving living donor Liver transplantation appear to possess significantly higher Tumor recurrence than the recipients receiving deceased donor Liver transplantation. The underlying mechanism for HCC recurrence after transplantation remains unclear. Here, we aim to investigate the impact of small-for-size Liver graft injury on HCC recurrence after transplantation. Methods The correlation between Tumor recurrence, Liver graft injury, CXCL10 expression and endothelial progenitor cell (EPC) mobilization was studied in 115 Liver transplant recipients and rat orthotopic Liver transplantation (OLT) models. The direct role of CXCL10/CXCR3 signaling on EPC mobilization was investigated in CXCL10 −/− mice and CXCR3 −/− mice. The role of EPCs on Tumor growth and angiogenesis was further investigated in an orthotopic Liver Tumor model. Results Clinically, patients with small-for-size Liver grafts ( p =0.04), accompanied by more circulating EPCs and higher early-phase intragraft and plasma CXCL10 levels, than the recipients with large grafts (⩾60% of SLW), which were further validated in rat OLT models. Circulatory EPC mobilization was reduced after Liver injury both in CXCL10 −/− mice and CXCR3 −/− mice in comparison to wild-type controls. CXCL10 recruited EPCs in dose-dependent and CXCR3-dependent manners in vitro . Early-phase EPC/CXCL10 injection enhanced orthotopic Liver Tumor growth, angiogenesis and metastasis in nude mice. Conclusions Post-transplant enhanced CXCL10/CXCR3 signaling in small-for-size Liver grafts directly induced EPC mobilization, differentiation and neovessel formation, which further promotes Tumor growth. Targeting CXCL10/CXCR3 signaling may attenuate early-phase Liver graft injury and prevent late-phase Tumor recurrence/metastasis after transplantation.
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FTY720 Suppresses Liver Tumor Metastasis by Reducing the Population of Circulating Endothelial Progenitor
2012Co-Authors: Yan Shao, Chang Chun Ling, Wei Geng, Xiao Bing Liu, Yuen Yuen, Sheung Tat Fan, Kwan ManAbstract:Background: Surgical procedures such as Liver resection and Liver transplantation are the first-line treatments for hepatocellular carcinoma (HCC) patients. However, the high incidence of Tumor recurrence and metastasis after Liver surgery remains a major problem. Recent studies have shown that hepatic ischemia-reperfusion (I/R) injury and endothelial progenitor cells (EPCs) contribute to Tumor growth and metastasis. We aim to investigate the mechanism of FTY720, which was originally applied as an immunomodulator, on suppression of Liver Tumor metastasis after Liver resection and partial hepatic I/R injury. Methodology/Principal Findings: An orthotopic Liver Tumor model in Buffalo rat was established using the hepatocellular carcinoma cell line McA-RH7777. Two weeks after orthotopic Liver Tumor implantation, the rats underwent Liver resection for Tumor-bearing lobe and partial hepatic I/R injury. FTY720 (2 mg/kg) was administered through the inferior caval vein before and after I/R injury. Blood samples were taken at days 0, 1, 3, 7, 14, 21 and 28 for detection of circulating EPCs (CD133+CD34+). Our results showed that intrahepatic and lung metastases were significantly inhibited together with less Tumor angiogenesis by FTY720 treatment. The number of circulating EPCs was also significantly decreased by FTY720 treatment from day 7 to day 28. Hepatic gene expressions of CXCL10, VEGF, CXCR3, CXCR4 induced by hepatic I/R injury were down-regulated in the treatment group
Hans Meine - One of the best experts on this subject based on the ideXlab platform.
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automatic Liver Tumor segmentation in ct with fully convolutional neural networks and object based postprocessing
Scientific Reports, 2018Co-Authors: Grzegorz Chlebus, Andrea Schenk, Jan Hendrik Moltz, Bram Van Ginneken, Horst K Hahn, Hans MeineAbstract:Automatic Liver Tumor segmentation would have a big impact on Liver therapy planning procedures and follow-up assessment, thanks to standardization and incorporation of full volumetric information. In this work, we develop a fully automatic method for Liver Tumor segmentation in CT images based on a 2D fully convolutional neural network with an object-based postprocessing step. We describe our experiments on the LiTS challenge training data set and evaluate segmentation and detection performance. Our proposed design cascading two models working on voxel- and object-level allowed for a significant reduction of false positive findings by 85% when compared with the raw neural network output. In comparison with the human performance, our approach achieves a similar segmentation quality for detected Tumors (mean Dice 0.69 vs. 0.72), but is inferior in the detection performance (recall 63% vs. 92%). Finally, we describe how we participated in the LiTS challenge and achieved state-of-the-art performance.
Hirota Fujiki - One of the best experts on this subject based on the ideXlab platform.
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Expression of the Tumor necrosis factor α gene and early response genes by nodularin, a Liver Tumor promoter, in primary cultured rat hepatocytes
Journal of cancer research and clinical oncology, 1997Co-Authors: Eisaburo Sueoka, Tetsuya Ohta, Masami Suganuma, Atsumasa Komori, Naoko Sueoka, Sachiko Okabe, Tomoko Kozu, S. J. Kim, In Kyoung Lim, Hirota FujikiAbstract:Nodularin is a new Liver carcinogen possessing a potent Tumor-promoting activity in rat Liver, mediated through inhibition of protein phosphatases 1 and 2A, and a weak initiating activity. Since we previously reported evidence that nodularin up-regulated expression of the Tumor necrosis factor α gene (TNFα) and early-response genes in rat Liver after its i.p. administration, and since TNFα had Tumor-promoting activity in vitro, it is possible that TNFα itself is involved in Liver Tumor promotion. We investigated whether hepatocytes themselves induce expression of theTNFα gene and early-response genes in primary cultured rat hepatocytes treated with nodularin. Like nodularin, microcystin-LR, which is another Liver Tumor promoter belonging to the okadaic acid class, strongly inducedTNFα gene expression in rat hepatocytes, as well as TNFα release from those cells into the medium. On the other hand, 12-O-tetradecanoylphorbol-13-acetate, which has been reported to induce no Tumor promotion in rat Liver, induced no apparent expression of theTNFα gene in primary cultured rat hepatocytes. As for the expression of early-response genes, 1 μM nodularin or microcystin-LR induced expression of the c-jun, jun B,jun D, c-fos, fos B andfra-1 genes in the hepatocytes, and the expression of these genes was prolonged up to 24 h, suggesting mRNA stabilization induced by inhibition of protein phosphatases 1 and 2A. This paper presents new evidence that theTNFα gene and early-response genes were expressed in hepatocytes treated with a Liver Tumor promoter.
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expression of the Tumor necrosis factor alpha gene and early response genes by nodularin a Liver Tumor promoter in primary cultured rat hepatocytes
Journal of Cancer Research and Clinical Oncology, 1997Co-Authors: Eisaburo Sueoka, Tetsuya Ohta, Masami Suganuma, Atsumasa Komori, Naoko Sueoka, Sachiko Okabe, Tomoko Kozu, S. J. Kim, In Kyoung Lim, Hirota FujikiAbstract:Nodularin is a new Liver carcinogen possessing a potent Tumor-promoting activity in rat Liver, mediated through inhibition of protein phosphatases 1 and 2A, and a weak initiating activity. Since we previously reported evidence that nodularin up-regulated expression of the Tumor necrosis factor α gene (TNFα) and early-response genes in rat Liver after its i.p. administration, and since TNFα had Tumor-promoting activity in vitro, it is possible that TNFα itself is involved in Liver Tumor promotion. We investigated whether hepatocytes themselves induce expression of theTNFα gene and early-response genes in primary cultured rat hepatocytes treated with nodularin. Like nodularin, microcystin-LR, which is another Liver Tumor promoter belonging to the okadaic acid class, strongly inducedTNFα gene expression in rat hepatocytes, as well as TNFα release from those cells into the medium. On the other hand, 12-O-tetradecanoylphorbol-13-acetate, which has been reported to induce no Tumor promotion in rat Liver, induced no apparent expression of theTNFα gene in primary cultured rat hepatocytes. As for the expression of early-response genes, 1 μM nodularin or microcystin-LR induced expression of the c-jun, jun B,jun D, c-fos, fos B andfra-1 genes in the hepatocytes, and the expression of these genes was prolonged up to 24 h, suggesting mRNA stabilization induced by inhibition of protein phosphatases 1 and 2A. This paper presents new evidence that theTNFα gene and early-response genes were expressed in hepatocytes treated with a Liver Tumor promoter.
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Liver Tumor promotion by the cyanobacterial cyclic peptide toxin microcystin-LR
Journal of Cancer Research and Clinical Oncology, 1992Co-Authors: Rie Nishiwaki-matsushima, Tetsuya Ohta, Kiyomi Kohyama, Masami Suganuma, Takatoshi Ishikawa, Shinji Nishiwaki, Hirota FujikiAbstract:Certain waterblooms of toxic cyanobacteria (blue-green algae) are a health threat because of their production of toxic peptides, termed microcystins, which cause Liver damage in wild and domesticated animals. The most widely studied microcystin is microcystin-LR, a heptapeptide containing the two l -amino acids, leucine and arginine. The inhibition of protein phosphatase type 1 and type 2A activities by microcystin-LR is similar to that of the known protein phosphatase inhibitor and Tumor promoter okadaic acid. We show in this report that microcystin-LR, applied below the acute toxicity level, dose-dependently increases the number and percentage area of positive foci for the placental form of glutathione S -transferase in rat Liver, which was initiated with diethylnitrosamine. The result was obtained independently through two animal experiments. This observation indicates that microcystin-LR is a new Liver Tumor promoter mediated through inhibition of protein phosphatase type 1 and type 2A activities. This provides further evidence that the okadaic acid pathway is a general mechanism of Tumor promotion in various organs, such as mouse skin, rat glandular stomach and rat Liver.
Aboul Ella Hassenian - One of the best experts on this subject based on the ideXlab platform.
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ct Liver Tumor segmentation hybrid approach using neutrosophic sets fast fuzzy c means and adaptive watershed algorithm
Artificial Intelligence in Medicine, 2019Co-Authors: Ahmed M Anter, Aboul Ella HassenianAbstract:Liver Tumor segmentation from computed tomography (CT) images is a critical and challenging task. Due to the fuzziness in the Liver pixel range, the neighboring organs of the Liver with the same intensity, high noise and large variance of Tumors. The segmentation process is necessary for the detection, identification, and measurement of objects in CT images. We perform an extensive review of the CT Liver segmentation literature. Furthermore, in this paper, an improved segmentation approach based on watershed algorithm, neutrosophic sets (NS), and fast fuzzy c-mean clustering algorithm (FFCM) for CT Liver Tumor segmentation is proposed. To increase the contrast of the Liver CT images, the intensity values are adjusted and high frequencies are removed using histogram equalization and median filter approach. It is followed by transforming the CT image to NS domain, which is described using three subsets (percentage of truth T, the percentage of indeterminacy I, and percentage of falsity F). The obtained NS image is enhanced by adaptive threshold and morphological operators to focus on Liver parenchyma. The enhanced NS image passed to a watershed algorithm for post-segmentation process and Liver parenchyma is extracted using the connected component algorithm. Finally, the Liver Tumors are segmented from the segmented Liver using fast fuzzy c-mean (FFCM). A quantitative analysis is carried out to evaluate segmentation results using six different indices. The results show that the overall accuracy offered by the employed neutrosophic sets is accurate, less time consuming, less sensitive to noise and performs better on non-uniform CT images.
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computational intelligence optimization approach based on particle swarm optimizer and neutrosophic set for abdominal ct Liver Tumor segmentation
Journal of Computational Science, 2018Co-Authors: Ahmed M Anter, Aboul Ella HassenianAbstract:Abstract In this paper, an improved segmentation approach for abdominal CT Liver Tumor based on neutrosophic sets (NS), particle swarm optimization (PSO), and fast fuzzy C-mean algorithm (FFCM) is proposed. To increase the contrast of the CT Liver image, the intensity values and high frequencies of the original images were removed and adjusted firstly using median filter approach. It is followed by transforming the abdominal CT image to NS domain, which is described using three subsets namely; percentage of truth T, percentage of falsity F, and percentage of indeterminacy I. The entropy is used to evaluate indeterminacy in NS domain. Then, the NS image is passed to optimized FFCM using PSO to enhance, optimize clusters results and segment Liver from abdominal CT. Then, these segmented Livers passed to PSOFCM technique to cluster and segment Tumors. The experimental results obtained based on the analysis of variance (ANOVA) technique, Jaccard Index and Dice Coefficient measures show that, the overall accuracy offered by neutrosophic sets is accurate, less time consuming and less sensitive to noise and performs well on non-uniform CT images.