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Objective Myocardial fibrosis is a potential mechanism of light-chain myocardial amyloidosis(AL-CA). This research aimed at exploring the correlation between multiparameter cardiac magnetic resonance (CMR) and myocardial fibrosis by relating the CMR myocardial tissue characteristics, the morphological and the functional parameters with gallium-68-labeledfibroblast activation protein inhibitor 04 positron emission tomography (68Ga-FAPI PET). Methods We gave the patients diagnosed with AL-CA in Peking Union Medical College Hospital from August to December 2021 the examinations of CMR and 68Ga-FAPI PET/CT. We recorded and analyzed the information on clinical manifestations and examinations of the patients. Results A total of 23 patients with AL-CA were included, 15 (65.2%)of which were male and the mean age was 58.3±6.5 years. Patients with high 68Ga-FAPI-04 uptake had shown growth in myocardial extracellular volume (ECV), significantly higher than those in the negative group (P=0.047). In addition, patients' myocardial ECV was positively correlated with myocardial FAPI uptake (r=0.628, P=0.001;r=0.727, P < 0.001;r=0.661, P=0.001). Patients in the positive group showd reduced left ventricular (LV) ejection fraction (EF)(P < 0.001).LVEF (r=-0.798, P < 0.001;r=-0.794, P < 0.001; r=-0.795, P < 0.001) and right ventricular (RV)EF (r=-0.735, P < 0.001;r=-0.739, P < 0.001;r=- 0.684, P < 0.001) showd negatively correlated with myocardial FAPI uptake, LV circumferential strain (r=0.668, P < 0.001;r=0.708, P < 0.001;r=0.705, P < 0.001), LV longitudinal strain (r=0.629, P=0.001;r=0.635, P=0.001; r=0.597, P=0.003), and RV longitudinal strain (r=0.575, P=0.004; r=0.792, P < 0.001;r=0.673, P < 0.001) were negatively correlated with myocardial FAPI uptake. Conclusions FAPI-related fibroblast activation is concurrent with CMR-related abnormal myocardial interstitial characteristics that leads to the decreased function of the myocardial movement. Patients with increased FAPI uptake present with increased ECV, decreased EF, and decreased strain with morphological abnormalities.
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Blau syndrome is a rare genetic disorder characterized by the a mix of granulomatous arthritis, uveitis, and dermatitis. Patients typically manifest multisystem involvement, including ocular, skin, and skeletal abnormalities. Blau syndrome is extremely rare, with a global incidence of less than one in a million among children. In this multidisciplinary consultation, we present a case of a 21-year-old young female patient having multisystemic involvement since early childhood. She was presented with multiple joint swelling, skin lesions, increased eye discharge, and accompanied by hypertension and arterial abnormalities, and received a diagnosis of uveitis. The patient had been receiving steroid treatment since the age of 6 and has tried various medications, with some improvement in joint swelling and ocular symptoms. Through this rare disease multidisciplinary consultation, we aim to provide guidance in the molecular diagnosis of the patient, multisystem assessment, and the selection and formulation of treatment plans. Additionally, we hope that by reporting this case, clinical physicians can gain a better understanding of the diagnosis and comprehensive treatment strategies for Blau syndrome, thereby improving the management and treatment of rare diseases.
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Objective:To evaluate the ability of 68Ga-Pentixafor (nuclide ligand imaging agents for chemokine receptor 4) PET/CT to differentiate between aldosterone-producing adenoma (APA) and adrenal nonfunctional adenoma (NFA), and to assess how well this imaging method correlates with clinical features and postoperative outcomes. Methods:This was a cross-sectional study involving 73 APA and 12 NFA patients who received 68Ga-Pentixafor PET/CT imaging at Peking Union Medical College Hospital from August 2018 to October 2021. The receiver operating characteristic (ROC) curve was used to evaluate the differential value of visual analysis and the maximum standard uptake value (SUV max) of the focus on APA and NFA. The related factors of SUV max, and its predictive effect on postoperative outcomes were analyzed using Pearson or Spearman analysis and χ2 text. Results:68Ga-Pentixafor PET/CT imaging was positive in 64 APA patients (sensitivity=87.7%) and negative in all 12 NFA patients (specificity=100%). The area under the ROC curve with SUV max differentiating APA and NFA was 0.932 ( P<0.001). When the SUV max cut-off point was 6.23, the sensitivity was 80.8% and the specificity was 100%. The SUV max correlated positively with lesion size ( r=0.598) and aldosterone/renin activity ratio ( r=0.313) and correlated negatively with potassium level ( r=-0.286), renin activity ( r=-0.240) and age of diagnosis ( r=-0.273) (all P<0.05). Of the patients who underwent adrenalectomy and received more than 6 months of post-surgical follow-up, the clinical complete remission rate was higher for 68Ga-Pentixafor PET/CT imaging-positive patients than imaging-negative patients (24/39 vs. 0/4, P=0.031). Conclusions:68Ga-Pentixafor PET/CT is effective at differentiating between APA and NFA. The SUV max of 68Ga-Pentixafor PET/CT correlates with age at onset, lesion size, and the severity of clinical manifestations, and is able to predict postoperative outcomes.
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Objective: A method for the determination of acetochlor and its metabolites in urine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was established. Methods: After cleaned-up by a HLB extraction cartridges, the urine was eluted with 1% acetic acid acetonitrile solution. The target compounds were separated by ACQUITY UPLC®HSS T3 Column (2.1 mm×100 mm×1.8 μm) by using 1% formic acid solution and acetonitrile as mobile phase with gradient elution program, and analyzed in positive electrospray ionization mode by liquid chromatography tandem mass spectrometry. Results: All the target compounds showed good linear relationships in the range of 1-50 μg/L, and the correlation coefficients (r) were higher than 0.997. The recoveries rates at three different spiked levels for all target compounds in blank matrices were 107.6%-129.1%, and the relative standard deviations (RSD) were 1.5%-9.9% (n=6) . The limits of detection and quantitation of the method were 0.04-0.11 μg/L and 0.15-0.42 μg/L, respectively, and target substances were detected in all urine samples from occupational exposure workers to acetochlor. Conclusion: This method is suitable for rapid screening and analysis of acetochlor and metabolites in urine with the advantages of accuracy, rapidity, simplicity, high sensitivity and good specificity.
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Humans , Acetonitriles , Chromatography, High Pressure Liquid , Chromatography, Liquid , Solid Phase Extraction , Tandem Mass Spectrometry , ToluidinesABSTRACT
Objective:To investigate the capability of 18F-FDG PET/CT imaging in monitoring combined immunotherapy response and detecting immune related adverse events (irAEs) in patients with advanced hepatobiliary carcinoma. Methods:From August 2018 to July 2019, 21 patients (14 males, 7 females, age (58.5±10.0) years) with advanced hepatobiliary carcinoma routinely underwent 66 18F-FDG PET/CT examinations in Peking Union Medical College Hospital. SUV max, the occurrence time and symptoms of irAEs were obtained and analyzed. Therapy response (complete metabolic response (CMR), partial metabolic response (PMR), stable metabolic disease (SMD), progressive metabolic disease (PMD)) was evaluated according to PET response criteria in solid tumors (PERCIST). Results:(1) Clinical results. Twenty-two irAEs occurred in 16 patients, while were not found in 5 patients. Six organs were involved, including thyroiditis(8), colitis(5), pneumonitis(4), rash(2), hepatitis(2), myositis and fasciitis(1). The appearance time of each irAEs were (103.0±58.0), (141.6±103.5), 34.0(6.0, 308.8), 9 and 117, 62 and 67, and 87 d after therapy, respectively. PET/CT detected all pneumonitis and myositis and fasciitis, but no rash and hepatitis were found. For colitis and thyroiditis, PET/CT detected 4 and 6 times respectively. (2) PET/CT signs of irAEs. Except thyroiditis, all irAEs lesions exhibited exudative changes in CT and high-avidity in PET. SUV max of the lesions were 9.0(7.9, 17.6) (colitis), 7.1±3.2 (thyroiditis), 5.3 and 8.6 (pneumonitis), 4.1 (myositis and fasciitis), respectively. (3) Therapy assessment. Among 21 patients, there were 7 for PMR, 9 for SMD, 5 for PMD, which were 7, 8, 1 in patients with irAEs and 0, 1, 4 in patients without irAEs. Conclusions:Patients with advanced hepatobiliary carcinoma can benefit from combined immunotherapy. 18F-FDG PET/CT can be used to evaluate the efficacy of immunotherapy by detecting the changes of tumor lesions and the occurrence of irAEs simultaneously. However, it is necessary to use CT to distinguish tumor progression from irAEs.
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In this paper, the domestic and international demand and development trend of clinical diagnostic radionuclides are analyzed, and the medium and high-energy cyclotrons, adequate and systematic facilities, and preparation techniques required for the production of medical radionuclides based on solid targets are introduced. This paper focuses on the research and development carried out by some important medical institutions and scientific research institutes in China over the years in the aspects of medium and high-energy cyclotrons, beam transmission lines, high-power irradiation target stations and new medical isotope production processes etc. It also looks forward to some new directions for the development of medical radionuclides in China during the 14th Five-Year Plan period.
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Objective:To explore the relation of the radiochemical purity and in vivo imaging effect of 68Ga-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA)- D-phe1-Tyr3-Thr8-octreotide (TATE) injection. Methods:High performance liquid chromatography (HPLC) and thin-layer chromatography (TLC) methods were established to determine 68Ga-DOTATATE, 68Ga 3+ , 68Ga in colloidal form and 68Ga-DOTA- D-Phe1-Tyr3-Thr8-dethreonine-octreotide (heptapeptide) and to study the influence of precursor purity on radiochemical purity of labelled products. The uptake of 68Ga-DOTATATE injection with different radiochemical purities was investigated in nude mice bearing AR42J cells by microPET imaging and the tumor target/non-target (T/NT) value was calculated. One-way analysis of variance and Pearson correlation analysis were used to analyze the data. Results:The contents of 68Ga 3+ and 68Ga in colloidal form were not related with precursor purity ( r values: 0.385, 0.497, P values: 0.306, 0.137), while the content of 68Ga-DOTA-heptapeptide was positively related with the purity of DOTA-heptapeptide ( r=0.957, P<0.001). The radiochemical purities of 68Ga-DOTATATE injection were (87.0±2.3)%, (86.8±0.8)% and (94.0±3.1)% when the DOTATATE purities were 90.9%, 91.6% and 99.2%, respectively. The results of microPET imaging showed that the tumor uptake was positively related with the radiochemical purity of 68Ga-DOTATATE injection ( r=0.828, P<0.001), and the T/NT values of 68Ga-DOTATATE injection with radiochemical purities of 95.7%, 85.8%, 84.5% and 79.9% were 21.25±8.84, 8.50±1.51, 11.38±1.65 and 6.01±0.99, respectively ( F=11.48, P=0.001). Conclusion:The radiochemical purity of 68Ga-DOTATATE injection is impacted by the purity of labelled precursor and manufacturing processes and is related with the imaging effect in vivo.
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Systematic light chain (AL) amyloidosis is the most common forms of amyloidosis, which manifests as multiple organ system involvement, rapid progress, dire prognosis, difficult therapy and high mortality. Many patients may miss the optimal treatment as a result of not being diagnosed timely. Therefore, early diagnosis and assessment of involved extent of AL are clinical focuses. Related clinical studies have demonstrated that nuclear medicine imaging can be non-invasive in detecting amyloid deposits. It can not only early assess the extent and distribution of amyloid deposits in systemic AL amyloidosis, but also offer the indications for risk stratification, treatment response monitoring and prognosis assessment of the patients, especially for positron amyloidosis-specific tracers, which may have great prospects in the future. This review summarizes the application of nuclear medicine imaging in the systematic AL amyloidosis.
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Objective:To analyze 18F-FDG PET/CT imaging features of non-functional pancreatic neuroendocrine neoplasms (NF-pNENs) and investigate its correlation with pathology and prognosis. Methods:A total of 35 cases (17 males, 18 females; age (51±12) years) of pathologically confirmed NF-pNENs who underwent pretherapeutic 18F-FDG PET/CT from January 2011 to July 2017 in Peking Union Medical College Hospital were retrospectively enrolled. Clinical data were collected and patients were followed up. PET/CT parameters including number and maximum diameter of lesions, SUV max and pancreatic tumor-to-liver ratio (T/L) were measured. Mann-Whitney U test and Kruskal-Wallis rank sum test, Spearman correlation analysis were used to analyze the data. Results:Among the included 35 NF-pNENs patients (G1, n=6; G2, n=21; G3, n=8) with maximum diameter of 3.0(2.1, 6.1) cm and SUV max of 5.5(4.0, 8.9), 32 were positive in PET/CT. There were 1 patient with cystic, 2 with calcification and 3 with dilatation of pancreaticobiliary duct. Among 10 patients with metastases, 8 revealed multiple liver metastases. There was statistical difference of T/L among G1-G3 tumor (1.23(0.60, 2.00), 3.05(1.80, 4.00), 3.90(1.90, 7.60); H=8.29, P=0.016), but there were no statistical differences of SUV max or maximum diameter among G1-G3 tumor ( H values: 4.34, 3.37, P values: 0.114, 0.186). There was a significant correlation between T/L (2.78(1.48, 3.94)) and Ki-67 index (8.0(3.0, 20.0); rs=0.631, P<0.001). Among 27 patients with available follow-up results, T/L in patients with complete remission or stable disease ( n=20) was statistically lower than that in patients with progressive disease or death ( n=7) (2.1(1.2, 3.2) vs 7.5(3.4, 13.4); z=-3.37, P=0.001). Conclusions:18F-FDG PET/CT can detect primary and metastatic lesions of NF-pNENs. T/L can better reflect the proliferative activity based on Ki-67 index than SUV max and it may be favorable on prognostic value.
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Immune checkpoint inhibitors (ICIs) have shown significant efficacy in clinical trials and applications of various malignant tumors, and have been approved for clinical application in China. ICIs can cause immune-related adverse events (irAEs), which may affect any organs. Early identification and appropriate treatment can improve patient outcome. 18F-FDG PET/CT is capable of early detection of irAEs and provides effective clinical guidance. This article reviews the clinical application of 18F-FDG PET/CT in detecting irAEs, including typical imaging findings and research progress.
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Objective:To investigate the application of different imaging methods of 99Tc m-pyrophosphate (PYP) in the diagnosis and pathological classification of cardiac amyloidosis (CA). Methods:A total of 31 patients (22 males, 9 females, age 21-81(57.2±13.4) years) with suspected CA who underwent 99Tc m-PYP dual-phase scintigraphy (early-phase: 1 h, delay-phase: 2-3 h) and SPECT/CT (1 h) between December 2018 and December 2019 in Peking Union Medical College Hospital were retrospectively included. Taking clinical diagnosis as the standard, the results of visual score (≥2, positive) and semi-quantitative values (heart to contralateral lung (H/CL)≥1.5, positive) of 99Tc m-PYP uptake in dual-phase scintigraphy and SPECT/CT imaging were analyzed. One-way analysis of variance and Bonferroni test were used to analyze the data. Results:Among 31 patients with suspected CA, 15 were clinically diagnosed as CA (5 patients with transthyretin-related CA (ATTR-CA) and 10 patients with light chain CA (AL-CA)) and 16 were diagnosed as non-CA. All 5 patients with ATTR-CA had positive dual-phase scintigraphy and SPECT/CT imaging results. Three out of 10 patients with AL-CA had positive early-phase scintigraphy whereas negative delay-phase scintigraphy and SPECT/CT imaging results. Sixteen patients who were clinically diagnosed as non-CA had negative dual-phase scintigraphy and SPECT/CT imaging results. The sensitivity (5/5), specificity (10/10), positive predictive value (5/5), negative predictive value (10/10) and accuracy (15/15) of delay-phase scintigraphy and SPECT/CT imaging were the same. Among 31 patients, 16 patients carried transthyretin-related (TTR) gene mutation, and 4 of them who clinically diagnosed as variant ATTR (ATTRv) had positive image findings while 12 of them who not clinically diagnosed as CA had negative image findings. There were significant differences in H/CL between ATTR-CA group and AL-CA group in early-phase (2.11±0.24 vs 1.31±0.07) and delay-phase (2.02±0.19 vs 1.30±0.05; F values: 75.41 and 87.15, Bonferroni test, both P<0.01). Conclusions:99Tc m-PYP delay-phase scintigraphy and SPECT/CT have high diagnostic efficiencies in ATTR-CA, helping to determine the pathological classification of CA; while early-phase scintigraphy has false positive results. Moreover, 99Tc m-PYP imaging is helpful to detect CA in patients with TTR gene mutation.
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A 15-year-old female was referred to the hospital with intermittent fever, where multiple systemic abnormalities were found, such as splenomegaly, secondary hypersplenism, retinitis pigmentosa, and ectodermal dysplasia. Medical history revealed that she had suffered recurrent respiratory infections, blurred vision at night, and dysplasia of teeth and nail beds since childhood. Then she was suspected to be experiencing ROSAH syndrome, a rare disease newly recognized in recent years, which was finally confirmed by gene sequencing results. During a course of treatment with tumor necrosis factor inhibitors, recurrent fever with elevated inflammatory markers reappeared, and the child developed headaches. To guide the comprehensive treatment and improve the patient's quality of life, the multidisciplinary team in Peking Union Medical College Hospital discussed together and directed the following treatment.
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Transthyretin-related amyloid cardiomyopathy (ATTR-CM) is a disease caused by the depo-sition of insoluble amyloid fibers formed by the misfolding of transthyretin precursor protein in the intercellular space of cardiomyocytes. This lesion may lead to myocardial dysfunction, cogestive heart failure, and death.When diagnosed earlier, the patient can be treated with drugs as soon as possible to intervene in the progress of the disease, so as to effectively improve the patient's prognosis.99mtechnetium-pyrophosphate (99Tcm-PYP)single-photon emission computed tomography (SPECT) has been widely used in the imaging examination of cardiac amyloidosis (CA) in recent years. While achieving early non-invasive diagnosis, accurate pathological classification can be obtained through Perugini visual score analysis, semi-quantitative analysis of heart to contralateral lung (H/CL) ratio, and SPECT image analysis. This article presents the application, methods, and the precautions of 99Tcm-PYPSPECT in the diagnosis of ATTR-CM, aiming to provide clinical reference for the application of this technology.
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Objective:To explore the clinical value of 68Ga-pentixafor PET/CT targeting for CXCR4 in the diagnosis and prognosis evaluation of primary aldosteronism (PA). Methods:Retrospective analysis was performed on information of 72 patients diagnosed with PA who received operations according to the results of 68Ga-pentixafor PET/CT in our hospital. There were 37 males and 35 females, with the average age of (48.3±9.5) years old. The average lesion diameter was (1.60 ± 0.54)cm. The preoperative systolic and diastolic blood pressure were (177.3 ± 23.9)mmHg and (107.6 ± 13.2)mmHg, respectively. The average preoperative potassium level was (2.62 ± 0.56)mmol/L. The average aldosterone concentration was (17.98 ± 4.66)ng/dl, and the median plasma renin activity was 0.01 (0.01, 0.09) ng/(ml·h). All patients underwent 68Ga-pentixafor PET/CT examination, which lead to the decision of surgical strategies. For those patients with single lesion, multiple lesions in one side or positive lesion in one side but negative in the opposite side, surgical resection of the positive side lesion or total adrenalectomy was considered. For those patients with bilateral positive lesions, surgical resection of the side with more significant positive lesions or total adrenalectomy was considered. For those with negative multiple lesions, the surgical strategy was designed according to the results of CT examination or AVS. The positive rate of 68Ga-pentixafor PET/CT and its relationship with the clinical characteristics and prognosis of patients were analyzed. Results:The results of 68Ga-pentixafor PET/CT were positive in 62 of 72 patients diagnosed with PA (86.1%), and the median SUVmax value was 11.1 (7.1, 16.2). The SUVmax value was positively correlated with the maximum diameter of adrenal lesion ( r=0.468) and negatively correlated with blood potassium levels ( r=-0.437), while not significantly correlated with other clinical characteristics. The positive rate of adenoma by 68Ga-pentixafor PET/CT was higher than that of nodular hyperplasia [90.5%(57/63) vs. 55.6%(5/9), P=0.018], and the SUVmax value in adenoma was also higher than that in nodular hyperplasia [11.9(7.8, 16.2) vs. 4.3(3.4, 11.3), P=0.022]. 32 cases were cured after operations, and 37 cases were improved. And 3 cases were not cured. The SUVmax value of lesions in the cured patients was higher than that in the improved patients [15.4(8.1, 22.7) vs. 10.1(6.8, 13.3), P=0.013]. Among 59 cases of PA patients with single adrenal lesions, 50 cases represented positive results of 68Ga-pentixafor PET/CT. 23 cases in 50 positive cases were cured and 27 cases were improved after resection of positive lesions. In the 13 PA patients with multiple adrenal lesions who underwent surgery according to the results of 68Ga-pentixafor PET/CT, 12 patients (92.3%) showed postoperative prognosis in line with preoperative expectations. Conclusions:68Ga-pentixafor PET/CT showed high positive rate in the diagnosis of PA, especially for adenoma.The SUVmax value of the adrenal lesion was correlated with the blood potassium level, the size of the lesion and the postoperative prognosis. In addition, 68Ga-pentixafor PET/CT could effectively guide the surgical decision of PA.
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Multi-centre clinical trials on PET/CT brain imaging are complex to organize and require careful co-ordination and management. This article describes considerations, which are necessary when designing and starting a multi-centre clinical trial on PET/CT brain imaging, based on guidelines and multi-center clinical brain imaging studies, providing references for further studies.
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Gaucher′s disease (GD) is a lysosomal storage disease, and the etiology of GD is the decreased activity of glucocerebrosidase, which leads to the accumulation of glucocerebroside in the lysosomes of macrophages. Because GD is rare and lacks specific clinical manifestations, it is easy to be misdiagnosed, which delays the best time for treatment. Early diagnosis, clinical evaluation, and regular monitoring of the disease have important clinical significance for enzyme replacement therapy in patients with GD. Recent studies have found that radionuclide imaging is playing an increasingly important role in the diagnosis and treatment of GD. This article introduces the application of radionuclide imaging in the diagnosis and management of GD.
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Objective:To investigate the segmentation methods of pancreatic ductal adenocarcinoma (PDAC) tumor regions in 18F-fluorodeoxyglucose (FDG) PET/CT images, as well as their impact on radiomic features-based pathological grade prediction. Methods:A total of 72 patients (46 males, 26 females, age range: 25-87 years) with pathologically confirmed PDAC and a preoperative 18F-FDG PET/CT scan in Peking Union Medical College Hospital between September 2010 and January 2016 were enrolled retrospectively. The cohort of patients was classified as well differentiated group and non-well differentiated group based on the pathological grade of PDAC, and patients were divided into training set and validation set in the ratio of 3∶1 randomly. Two physicians performed manual contours in the tumor region (referred as region of interest (ROI)_M1 and ROI_M2) and semi-automatic ROIs based on standardized uptake value (SUV) gradient edge search (referred as ROI_G) and 40% threshold applied to the maximum SUV (SUV max; referred as ROI_S) were drawn. The four types of segmentation results were compared in terms of volume and Dice similarity coefficient (DSC). Shape, first-order, and texture features were extracted from PET/CT original and preprocessed images, and the interclass correlation coefficient (ICC) was used to assess each feature′s consistency across all segmentations. Kruskal-Wallis rank sum test, independent-sample t test or z test were used to analyze the data. The area under the receiver operating characteristic curve was used to assess model accuracy, and cross validation was used to assess generalization ability. Results:There were 55 patients in the training set (14 well differentiated cases and 41 non-well differentiated cases) and 17 patients in the validation set (4 well differentiated cases and 13 non-well differentiated cases). A total of 44 selected features were predictive of the pathological grade of PDAC among 20 feature groups. There was significant difference among the volumes of ROI_M1, ROI_M2, ROI_G and ROI_S (10.29(4.01, 19.43), 9.34(4.26, 17.27), 11.86(5.52, 19.74) and 15.08(9.62, 27.44) cm 3; H=18.641, P<0.05). The degree of contour coincidence and feature consistency between ROI_M1 and ROI_M2 were both higher (DSC=0.86 (0.76, 0.90), ICC=0.86 (0.74, 0.94)). Compared to manual contours, the degree of contour coincidence and feature consistency of ROI_G (DSC: 0.86(0.75, 0.91), 0.91(0.85, 0.96); ICC: 0.87(0.72, 0.94), 0.94(0.88, 0.98)) were better. There was no statistically significant difference in model accuracy or generalization ability between ROI_M1 and ROI_G ( z=1.052, t=0.712, both P>0.05). The accuracy of ROI_M2 was better than ROI_G ( z=3.031, P=0.002), but the generalization ability of ROI_M2 was insufficient ( t=3.086, P=0.012). Conclusions:Although the manual contour prediction models are highly accurate, their performance are unstable. Semi-automatic contouring based on gradient can achieve comparable accuracy to manual contouring, and the model′s generalization ability is stronger.
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Objective:To investigate the radiation dosimetry and biodistribution of 68Ga-FAPI-04 PET/CT in patients with hepatobiliary tumor. Methods:A total of six patients with hepatic lesions who underwent PET/CT examination in Peking Union Medical College Hospital were enrolled. After intravenous injection of radiotracer 68Ga-FAPI-04 at (170.57 ± 14.43) MBq, whole-body imaging were performed at the time points of 3, 10, 15, 20, 30 and 60 min, respectively. Biodistribution pattern was observed. Regions of interest were manually delineated. Radiation dosimetry of all target organs were calculated by Olinda/EXM software. Results:The radioactive uptake dissipated gradually in liver whereas it was relatively stable in tumor lesions. The average SUV max of tumor lesions reached the maximum value (13.87± 2.55) at 20 min after injection. The target-to-background ratio increased with time, reaching the maximum value (10.09 ± 8.17) at 30 min after injection. The average effective dose in total body was (0.020 ± 0.002) mSv/MBq and organ with the highest effective dose was bladder wall at (0.146 ± 0.035) mSv/MBq. Conclusions:The effective dose in total body of 68Ga-FAPI-04 was similar to that of 18F-FDG. 68Ga-FAPI-04 is expected to be a PET/CT radiotracer for hepatobiliary tumors in consideration of rapid tumor uptake, low accumulation of liver background, and no influence of blood sugar levels.
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Pancreatic neuroendocrine neoplasms (pNENs) are highly heterogeneous, and the management of pNENs patients can be intractable. To address this challenge, an expert committee was established on behalf of the Chinese Pancreatic Surgery Association, Chinese Society of Surgery, Chinese Medical Association, which consisted of surgical oncologists, gastroenterologists, medical oncologists, endocrinologists, radiologists, pathologists, and nuclear medicine specialists. By reviewing the important issues regarding the diagnosis and treatment of pNENs, the committee concluded evidence-based statements and recommendations in this article, in order to further improve the management of pNENs patients in China.
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Objective To design a novel automatic dispensing and injecting system of positron radiopharmaceuticals,for precise dose dispensing,simplified operation,and reduction of occupational radiation exposure. Methods The automatic dispensing and injecting system was fabricated with tungsten alloy as the shielding material.The performance and radiation protection of the device were assessed. Results The total time of injection using the automatic dispensing and injecting system was about 60 s.The ratio of successful injection in stability test was 100%.The deviation of the dispensing dose with the system was ≤3%.With the tungsten alloy shield(40 mmPb of the cabinet,60 mmPb of the countertop,15 mmPb of the protective shield,and 50 mmPb of the inbuilt jar for radiopharmaceuticals),the average dose rate at 30 cm from the device was 1.44 μSv/h,and the radiation dose at the operator's extremity was reduced by 99%. Conclusions This automatic dispensing and injecting system of positron radiopharmaceuticals is easy to operate with precise dispensing dose.It is safe and meets the requirements of radiation protection.