Hepatocellular Carcinoma and the Function involving Liver Transplantation An overview

Postradioembolization lung absorbed dose verification was historically problematic and impractical in clinical practice. We devised an indirect method using 90Y PET/CT. Methods Conceptually, true lung activity is simply the difference between the total prepared activity minus all activity below the diaphragm and residual activity within delivery apparatus. Patient-specific lung mass is measured by CT densitovolumetry. True lung mean absorbed dose is calculated by MIRD macrodosimetry. Results Proof of concept is shown in a hepatocellular carcinoma patient with a high lung shunt fraction of 26%, where evidence of technically successful hepatic vein balloon occlusion for radioembolization lung protection was required. Indirect lung activity quantification showed the postradioembolization lung shunt fraction to be reduced to approximately 1% with a true lung mean absorbed dose of approximately 1 Gy, suggesting complete lung protection by hepatic vein balloon occlusion. Conclusion We discuss possible clinical applications such as lung absorbed dose verification, refining the limits of lung tolerance, and the concept of massive activity radioembolization.Development and spread of cancer is a multi-step and complex process which involves number of alterations, interactions and molecular networks. PET imaging is closely related with biology of cancer as it detects the cancer based on biological and pathological changes in tumor cells and tumor microenvironment. In this review article, biology of development and spread of cancer and role of PET imaging in Oncology was summarized and supported with various PET images demonstrating cancer spread patterns.18F-FDG PET/CT quantification of whole-body tumor burden in lymphoma is not routinely performed because of the lack of fast methods. Although the semiautomatic method is fast, it is not fast enough to quantify tumor burden in daily clinical practice. Our purpose was to evaluate the performance of convolutional neural network (CNN) software in localizing neoplastic lesions in whole-body 18F-FDG PET/CT images of pediatric lymphoma patients. Methods The retrospective image dataset, derived from the data pool of the International Atomic Energy Agency (coordinated research project E12017), included 102 baseline staging 18F-FDG PET/CT studies of pediatric lymphoma patients (mean age, 11 y). The images were quantified to determine the whole-body tumor burden (whole-body metabolic tumor volume [wbMTV] and whole-body total lesion glycolysis [wbTLG]) using semiautomatic software and CNN-based software. Both were displayed as semiautomatic wbMTV and wbTLG and as CNN wbMTV and wbTLG. The intraclass correlation coefficient (ICC) was applied to evaluate concordance between the CNN-based software and the semiautomatic software. Results Twenty-six patients were excluded from the analysis because the software was unable to perform calculations for them. In the remaining 76 patients, CNN and semiautomatic wbMTV tumor burden metrics correlated strongly (ICC, 0.993; 95% CI, 0.989 - 0.996; P less then 0.0001), as did CNN and semiautomatic wbTLG (ICC, 0.999; 95% CI, 0.998-0.999; P less then 0.0001). However, the time spent calculating these metrics was significantly ( less then 0.0001) less by CNN (mean, 19 s; range, 11-50 s) than by the semiautomatic method (mean, 21.6 min; range, 3.2-62.1 min), especially in patients with advanced disease. Conclusion Determining whole-body tumor burden in pediatric lymphoma patients using CNN is fast and feasible in clinical practice.This study measured the typical emitted radiation rate from the urinary bladder of PET patients after their scan and investigated simple methods for reducing the emitted radiation before discharge. Methods The study included 83 patients (63 18F-FDG and 20 18F-NaF patients). Emitted radiation from the patients' urinary bladder was measured with an ionization survey meter at a 1-m distance, presuming the urinary bladder to be the primary source of radiation. The measurements were taken at different time points after PET image acquisition immediate (prevoid 1), voided (postvoid 1), after waiting 30 min in the uptake room while drinking 500 mL of water (prevoid 2), and voided again (postvoid 2). Results For 18F-FDG patients, the reduction of emitted radiation due to drinking water and voiding alone from prevoid 1 to decay-corrected postvoid 2 was an average of 22.49% ± 7.48% (13.65 ± 3.42 μSv/h to 10.48 ± 2.37 μSv/h, P less then 0.001). For 18F-NaF patients, the reduction was an average of 25.80% ± 10.03% (9.83 ± 2.01 μSv/h to 7.23 ± 1.49 μSv/h, P less then 0.001). Conclusion In addition to the physical decay of the radiotracers, using the biologic clearance properties resulted in a significant decrease of the emitted radiation in this study. Implementing additional water consumption to facilitate voiding with 30 min of wait time before discharging certain 18F-FDG and 18F-NaF patients who need to be in close contact with others, such as elderly, caregivers, and inpatients, might facilitate lowering their emitted radiation by an average of 22%-25% due to voiding, not counting in the physical decay that should add an additional 17% reduction.This study investigated the spatial resolution and image quality of the continuous bed motion (CBM) method in a sensitive silicon photomultiplier (SiPM)-based positron emission tomography (PET)/computed tomography (CT) system compared with the traditional step-and-shoot (SS) method. Methods Siemens Biograph Vision was used in this study. Data acquisition using the SS method was performed for 3 min per bed. In the CBM method, the bed speed ranged from 0.5 to 3.3 mm/s. The acquisition time equivalent to the SS method was 1.1 mm/s for 2-bed ranges and 0.8 mm/s for seven-bed ranges. The spatial resolution was investigated using 18F point sources and evaluated using the full width at half maximum. Image quality was investigated using a National Electrical Manufacturers Association International Electrotechnical Commission body phantom with six spheres 10-, 13-, 17-, 22-, 28-, and 37-mm inner diameters. The radioactivity concentration ratio of the 18F solution in all spheres and the background was approximately 41.solution and image quality in whole body PET images with same acquisition time using the SS method.Total-body PET/CT allows simultaneous acquisition of all the body parts in a single bed position during the radiotracer uptake phase. Dynamic imaging protocols employing total-body PET could demonstrate findings that may not have been previously visualized or described using conventional PET/CT scanners. We examined the characteristics of blanching defects, areas of markedly reduced (partial defect) or absent (complete defect) radiotracer uptake seen at the skin/subcutaneous tissues opposite the bony prominences at pressure points. Methods In this observational study, 77 participants underwent dynamic total-body PET/CT imaging using 18F-FDG (Group 1, N = 47, 60-min dynamic, arms-down, divided into 3 subgroups according to the injected dose) or 18F-fluciclovine (Group 2, N = 30, 25-min dynamic, arms above the head). 40 out of 47 participants in Group 1 were re-imaged at 90 min after being allowed off the scanning table. Blanching defects, partial or complete, were characterized opposite the bony prominences at are common on dynamic total-body PET/CT images using different radiopharmaceuticals and injection doses. Their appearance should not be immediately interpreted as an abnormality. The current findings warrant further exploration in a prospective setting and may be utilized to study various mechano-pathologic conditions, such as pressure ulcers.Dual tracer PET/CT examinations (18F-FDG/68Ga-DOTATATE) have become an established practice in management of metastatic Neuroendocrine neoplasms (NENs) and demonstrates the advantages of deciphering the molecular PET characteristics of the tumor in patient management. Etomoxir Judicious elucidation of the findings is important, especially in scenarios of discordance with reported histopathology; this can lead to unsuspected diagnosis such as second primary malignancies (SPMs). Such diagnosis established in early disease course and mostly in an asymptomatic stage, provides patient a lead time for timely appropriate management. This concept is elaborated with a case-example of incidentally detected 18F-FDG avid metachronous adenocarcinoma lung in a patient of metastatic well-differentiated gastric NEN, wherein dual tracer PET/CT assessment had demonstrated FDG avid but non-68Ga-DOTATATE avid lung opacity.Polycomb repressive complex 2 (PRC2) is involved in maintaining transcriptionally silent chromatin states through methylating lysine 27 of histone H3 by the catalytic subunit enhancer of zeste [E(z)]. Here, we report the diversity of PRC2 core subunit proteins in different eukaryotic supergroups with emphasis on the early-diverged lineages and explore the molecular evolution of PRC2 subunits by phylogenetics. For the first time, we identify the putative ortholog of E(z) in Discoba, a lineage hypothetically proximal to the eukaryotic root, strongly supporting emergence of PRC2 before the diversification of eukaryotes. Analyzing 283 species, we robustly detect a common presence of E(z) and ESC, indicating a conserved functional core. Full-length Su(z)12 orthologs were identified in some lineages and species only, indicating, nonexclusively, high divergence of VEFS-Box-containing Su(z)12-like proteins, functional convergence of sequence-unrelated proteins, or Su(z)12 dispensability. Our results trace E(z) evolution within the SET-domain protein family, proposing a substrate specificity shift during E(z) evolution based on SET-domain and H3 histone interaction prediction.
Colchicine has been proposed as a COVID-19 treatment.
To determine whether colchicine reduces time to recovery and COVID-19-related admissions to hospital and/or deaths among people in the community.
Prospective, multicentre, open-label, multi-arm, randomised, controlled, adaptive platform trial (PRINCIPLE).
Adults aged ≥65 years or ≥18 years with comorbidities or shortness of breath, and unwell for ≤14 days with suspected COVID-19 in the community, were randomised to usual care, usual care plus colchicine (500 µg daily for 14 days), or usual care plus other interventions. The co-primary endpoints were time to first self-reported recovery and admission to hospital/death related to COVID-19, within 28 days, analysed using Bayesian models.
The trial opened on 2 April 2020. Randomisation to colchicine started on 4 March 2021 and stopped on 26 May 2021 because the prespecified time to recovery futility criterion was met. The primary analysis model included 2755 participants who were SARS-CoV-2 positive, randomised to colchicine (
= 156), usual care (
= 1145), and other treatments (
= 1454). Time to first self-reported recovery was similar in the colchicine group compared with usual care with an estimated hazard ratio of 0.92 (95% credible interval (CrI) = 0.72 to 1.16) and an estimated increase of 1.4 days in median time to self-reported recovery for colchicine versus usual care. The probability of meaningful benefit in time to recovery was very low at 1.8%. COVID-19-related admissions to hospital/deaths were similar in the colchicine group versus usual care, with an estimated odds ratio of 0.76 (95% CrI = 0.28 to 1.89) and an estimated difference of -0.4% (95% CrI = -2.7 to 2.4).
Colchicine did not improve time to recovery in people at higher risk of complications with COVID-19 in the community.
Colchicine did not improve time to recovery in people at higher risk of complications with COVID-19 in the community.