To evaluate the novel SPECT tracer 99mTc-CN7DG in a first-in-human clinical trial and assess its diagnostic value for central nervous system (CNS) tumors. Five Healthy volunteers were enrolled to assess the safety, biodistribution, and dosimetry of 99mTc-CN7DG. Subsequently, we prospectively enrolled 20 patients suspected a CNS tumor underwent MR, 18F-FDG PET/CT, and 99mTc-CN7DG quantitative SPECT/CT. The number of lesions and semi-quantitative parameters including the SUVmax, SUVmean, SUVmin, and lesion-to-background ratio (LBR) were measured. No adverse reactions were observed in any volunteers or patients after the injection of 99mTc-CN7DG. The mean whole-body effective dose estimated was 5.24 × 10⁻³ mSv/MBq. A total of 45 lesions were analyzed. Based on patient analysis, the detection rate was 90.0

BACKGROUND:With a 3D model reconstructed from coronary angiography, intracoronary blood flow can be calculated using a computational fluid dynamics (CFD) model with fractional flow reserve (FFR) measured pressure as boundary conditions. AIMS:The aim of this study is to investigate the clinical feasibility of this method by evaluating its ability to identify myocardial ischemia diagnosed by SPECT myocardial perfusion imaging (MPI). METHODS:Patients who underwent both SPECT-MPI and coronary angiography with FFR within 1 week were enrolled. Based on the summed stress score (SSS) and summed difference score (SDS) of SPECT MPI, myocardial ischemia in individual coronary territories was identified. Mean flow rate (Q), total flow resistance (TFR), absolute microvascular resistance (AMR) and their corresponding resting state indices were computed using the novel CFD model. RESULTS:A total of 52 patients with 53 vessels were investigated. Based on SPECT MPI, 23 patients (43.4%) were associated with abnormal MPI. Q was significant higher in normal MPI group compared with abnormal MPI group (59.68 ± 40.33 mL/min vs. 25.67 ± 21.55 mL/min, p < 0.001). The TFR were significantly lower in normal MPI group (TFR: 1898.25 ± 951.55 mmHg min/L vs. 4786.31 ± 3056.18 mmHg min/L, p < 0.001). The ROC-AUC of Q and TFR for discriminating normal and abnormal MPI were 0.876 (95% CI: 0.783-0.970, p < 0.001) and 0.854 (95% CI: 0.745-0.963, p < 0.001). CONCLUSIONS:Intracoronary flow assessed by the novel CFD based method has shown promise in accurately identifying patients with abnormal SPECT MPI, offering a convenient and quantitative approach for assessing coronary physiology.

To assess myocardial injury using rest single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients with COVID-19 and to evaluate whether myocardial injury detected by rest MPI predict the prognosis of symptoms after 6 months follow-up. Patients suspected of myocarditis between December 2022 and March 2023, after the lifting of COVID-19 pandemic restrictions, and between December 2018 and March 2019, prior to the pandemic, were referred to our study. All patients underwent rest MPI. One hundred and sixty four patients with COVID-19 infection after the lifting of pandemic restrictions and 101 patients before the pandemic were included as the study and control groups, respectively. One hundred and fifty three patients of the study group and 83 of the control group presented symptoms when they initially visit to our department. Compare the parameters of myocardial injury detected by rest SPECT MPI between the two groups and then investigate the association between myocardial injury and symptom prognosis in symptomatic patients of both groups. Total perfusion defect (TPD) (4.2

Background A novel computational fluid dynamics (CFD) based method was proposed for the measurement of intracoronary mean flow rate ( Q ) and absolute microvascular resistance ( AMR ) by combining coronary angiography and routine fractional flow reserve (FFR) measurement. The aim of this study is to explore the potential of the proposed method to assess the presence of coronary microvascular dysfunction (CMD). Methods Patients without hemodynamically significant coronary artery stenosis or those after a successful PCI were enrolled. Rest SPECT myocardial perfusion imaging (MPI) was employed as evidence for assessing the presence of CMD. Based on the sum rest score of target vessel ( SRSTV ), patients were divided into normal MPI group ( SRSTV ≤ 1) and abnormal MPI group ( SRSTV > 1). Q and AMR were obtained with a CFD based method during rest and hyperemia condition, and receiver operating characteristic (ROC) curve analyses were performed for discriminating patients with normal MPI and with abnormal MPI. Results A total of 57 patients with 61 target vessels were investigated. Based on SRSTV , 22 patients (38.6%) with 23 target vessels (37.7%) were associated with abnormal MPI. Compared with abnormal MPI group, the AMR was significantly lower in normal MPI group (1.97 ± 1.50 mmHg·s/ml vs 3.41 ± 2.30 mmHg·s/ml, p = 0.011), and the Q was significant higher in normal MPI group (0.94 ± 70 mmHg·s/ml vs 0.56 ± 0.50 mmHg·s/ml, p = 0.025). According to ROC curve analysis, the ROC-AUC of Q and AMR for discriminating normal MPI and abnormal MPI was 0.720(95% CI: 0.591–0.828, p = 0.001) and 0.731(95% CI: 0.602–0.836, p = 0.001). Conclusions The new CFD based method provides an easy and accurate way to measure the intracoronary flow rate and absolute microvascular resistance, and constitutes a new opportunity for assessing the presence of CMD.

ObjectiveThere is currently no non-invasive examination that can fully determine the diagnosis of osteomyelitis. SPECT/CT tomographic fusion imaging can provide both local metabolic activity and anatomical information to determine the condition and location. This study evaluates the diagnostic efficacy of 99mTc-MDP SPECT/CT in bone infections, compared to MRI.MethodsIn this multicenter retrospective study, 363 patients with suspected bone and joint infections or osteomyelitis were included. Participants underwent 99mTc-MDP SPECT/CT and/or MRI examinations, supplemented by pathogenic bacterial cultures and histopathological analysis.ResultsOnly SPECT/CT was tested in 169 patients, and only MRI was used in 116. 78 people have implemented both inspections and have detailed information. The diagnostic sensitivity and specificity of SPECT/CT for infection were 96% and 92% respectively, with an accuracy of 96%. For MRI, these figures were 88%, 84%, and 87% respectively.ConclusionThis represents the largest global study to date evaluating osteomyelitis and bone infection diagnosis using 99mTc-MDP SPECT/CT tomographic fusion imaging. The findings indicate that 99mTc-MDP SPECT/CT fusion imaging offers superior diagnostic accuracy compared to MRI. This is particularly evident in cases involving metallic implants and chronic infections. 99mTc-MDP SPECT/CT fusion imaging emerges as a highly suitable non-invasive diagnostic modality, facilitating enhanced clinical follow-up and treatment.

Over the past decade, [68Ga]Ga-FAPI-04 positron emission tomography (PET)/CT imaging has been widely used for the treatment of various tumors. However, the application of 99mTC-labeled fibroblast activation protein inhibitors in tumors has been less studied. Our team previously demonstrated the safe biological distribution of [99mTc]Tc-DP-FAPI in the human body. Based on this, this study reports the accuracy of [99mTc]Tc-DP-FAPI in the imaging diagnosis of gastrointestinal tumors and compares it with that of [68Ga]Ga-FAPI-04 to evaluate the differences. A total of 24 patients with clinically diagnosed gastrointestinal tumors were prospectively included. All patients received [99mTc]Tc-DP-FAPI quantitative SPECT/CT imaging on the first day and [68Ga]Ga-FAPI-04 PET/CT imaging on the second day. And the effectiveness of the two imaging probes in detecting suspicious lesions was analyzed and compared. The primary tumors of all 24 patients were well detected by two imaging probes, and the sensitivity of [99mTc]Tc-DP-FAPI and [68Ga]Ga-FAPI-04 to the primary lesions was 100%. [99mTc]Tc-DP-FAPI examined 21 lymph nodes with a sensitivity and specificity of 32.8% and 10.9%, and [68Ga]Ga-FAPI-04 detected 57 lymph nodes with a sensitivity and specificity of 89.1% and 67.2%, respectively. Three distant metastases were detected by [99mTc]Tc-DP-FAPI and nine metastases by [68Ga]Ga-FAPI-04. The study showed that [99mTc]Tc-DP-FAPI is highly sensitive to detecting primary lesions of gastrointestinal tumors. Compared with [68Ga]Ga-FAPI-04, [99mTc]Tc-DP-FAPI has the same sensitivity in detecting primary tumors but has certain limitations in detecting metastases. [99mTc]Tc-DP-FAPI is of great value for preliminary screening of tumor lesions and early diagnosis of disease in patients who are suspected of having gastrointestinal tumors.

Fibroblast activation protein (FAP) is a potential target for tumor diagnosis and treatment because it is selectively expressed on the cell membrane of cancer-associated fibroblasts in most solid tumor stroma. The aim of this study was to develop a 99mTc-labeled fibroblast activation protein inhibitor (FAPI) tracer, evaluate its imaging efficacy in nude mice, and further explore its biodistribution in healthy volunteers and uptake in tumor patients. An FAPI-derived ligand (DP-FAPI) containing d-proline was designed and synthesized as a linker, and a stable hydrophilic 99mTc-labeled complex ([99mTc]Tc-DP-FAPI) was obtained by kit formulation. In vitro cellular uptake and saturation binding assays were performed in FAP-transfected HT-1080 cells (FAP-HT-1080). The biodistribution was characterized, and micro-single-photon emission computed tomography (SPECT) imaging was performed in BALB/c nude mice bearing U87 MG tumors. Furthermore, a first-in-man application was performed in four healthy volunteers and three patients with gastrointestinal tumors. In vitro, the nanomolar Kd values of [99mTc]Tc-DP-FAPI indicated that it had significantly high target affinity for FAP. Biodistribution and micro-SPECT imaging studies showed that [99mTc]Tc-DP-FAPI exhibited high uptake and high tumor-to-nontargeted ratios. The calculated effective dose for [99mTc]Tc-DP-FAPI was approximately <5 mSv in four healthy volunteers. In three patients with gastrointestinal tumors, [99mTc]Tc-DP-FAPI quantitative SPECT/CT revealed high and reliable uptake. [99mTc]Tc-DP-FAPI exhibited high selectivity and affinity for FAP in vitro. The safety and effectiveness of [99mTc]Tc-DP-FAPI in primary tumor imaging have been confirmed by animal and clinical studies, revealing the potential clinical application value of this tracer.

Coronavirus disease 2019 (COVID-19) is a serious threat to public health and is in urgent need of specific drugs. Meplazumab, a humanized monoclonal antibody targeting CD147, was confirmed to competitively block the binding between the spike of syndrome coronavirus 2 (SARS-CoV-2) and CD147, making meplazumab a promising candidate drug for COVID-19. In this study, biodistribution and dosimetry of 131I-labeled meplazumab were performed to further evaluate its potential as a therapeutic drug for COVID-19. 131I-meplazumab was both safe and tolerant in mice and healthy volunteers. A biodistribution study was performed in normal mice, and blood samples were used for pharmacokinetic analysis. Three healthy volunteers were included and subjected to single-photon-emission computed tomography (SPECT) imaging of 131I-meplazumab within 2 weeks. The distribution in mice and humans was consistent with the in vivo distribution of CD147. Biodistribution and SPECT imaging results exhibited that the liver was the organ with the highest uptake for both mice and humans. Deiodination of 131I-meplazumab can be observed in vivo, and taking Lugol’s solution can protect the thyroid gland effectively. The pharmacokinetic characteristics of 131I-meplazumab in mice and humans best fit the two-compartment model. The clearance half-life (T 1/2β) in mice and humans was 117.4 and 223.5 h, respectively. The results indicated that its pharmacokinetic properties in vivo were ideal. The effective dose calculated from healthy volunteers was 0.811 ± 0.260 mSv·MBq–1, which was twice the value calculated from mice. It was safe and feasible to perform human clinical imaging experiments using a diagnostic dose of 131I-meplazumab after thyroid closure by Lugol’s solution. This study will provide more experimental basis for advancing the clinical translation of meplazumab and will be valuable in evaluating therapeutic interventions for patients with COVID-19, as well as providing a reference for clinical translation studies of other antibody drugs.

Abstracts Recent evidence suggests that CD147 serves as a novel receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Blocking CD147 via anti-CD147 antibody could suppress the in vitro SARS-CoV-2 replication. Meplazumab is a humanized anti-CD147 IgG2 monoclonal antibody, which may effectively prevent SARS-CoV-2 infection in coronavirus disease 2019 (COVID-19) patients. Here, we conducted a randomized, double-blinded, placebo-controlled phase 1 trial to evaluate the safety, tolerability, and pharmacokinetics of meplazumab in healthy subjects, and an open-labeled, concurrent controlled add-on exploratory phase 2 study to determine the efficacy in COVID-19 patients. In phase 1 study, 59 subjects were enrolled and assigned to eight cohorts, and no serious treatment-emergent adverse event (TEAE) or TEAE grade ≥3 was observed. The serum and peripheral blood C max and area under the curve showed non-linear pharmacokinetic characteristics. No obvious relation between the incidence or titer of positive anti-drug antibody and dosage was observed in each cohort. The biodistribution study indicated that meplazumab reached lung tissue and maintained >14 days stable with the lung tissue/cardiac blood–pool ratio ranging from 0.41 to 0.32. In the exploratory phase 2 study, 17 COVID-19 patients were enrolled, and 11 hospitalized patients were involved as concurrent control. The meplazumab treatment significantly improved the discharged (P = 0.005) and case severity (P = 0.021), and reduced the time to virus negative (P = 0.045) in comparison to the control group. These results show a sound safety and tolerance of meplazumab in healthy volunteers and suggest that meplazumab could accelerate the recovery of patients from COVID-19 pneumonia with a favorable safety profile.

Objective:To explore the application value of radioisotope tracer technology in clinical research of biological drugs.Methods:The pharmacokinetic properties of mepuzumab in healthy volunteers were evaluated by measuring the radioactive concentrations of iodine in blood and urine samples of 3 healthy volunteers at different time points within 14 days after intravenous infusion of 131I-labeled international class I new drug mepuzumab (Trial 1). Positron emission computed tomography (PET/CT) was performed on 6 healthy volunteers after intravenous injection of 68Ga-labeled nucleic acid aptamer Sgc8, and the standard uptake values of 68Ga-Sgc8 in different organs were measured to evaluate its biodistribution in healthy humans (Trial 2). Nine patients with suspected neuroendocrine tumors underwent single photon emission and X-ray computed tomography (SPECT/CT) 4 hours after intravenous injection of 99mTc-labeled octreotide to determine the radioactive uptake level in the regions of interest; the affinity and targeting of 99mTc-labeled octreotide to somatostatin receptor subtype 2 (SSTR2) were evaluated in combination with the immunohistochemical staining results of SSTR2 in patients′ biopsy tissues (Trial 3). Results:The 3 healthy volunteers included in Trial 1 were male, aged 28, 45, and 25 years respectively; the injection doses of 131I-labeled mepuzumab were 21.0, 25.9, and 17.6 mg, and the injection doses of radioactivity were 364, 420, and 304 MBq, respectively. Among the 6 healthy volunteers included in Trial 2, 3 were male and 3 were female, with an age of (46±11) years, ranging from 35 to 63 years. The dose of radioactivity injected was (80±7) MBq, ranging from 69 to 87 MBq. Among the 9 patients included in Trial 3, 5 were male and 4 were female, with an age of (54±10) years, ranging from 39 to 69 years. The dose of radioactivity injected was (777±74) MBq, ranging from 740 to 925 MBq. After intravenous infusion of 131I-labeled mepuzumab, the blood radioactivity concentration reached the peak 1.5 hours later. 131I-labeled mepuzumab mainly bound to blood cells, and its whole-blood clearance half-life was 420 hours. The urine radioactivity concentration reached the peak 16-24 hours after administration and then gradually decreased after 24 hours of administration. After intravenous injection of 68Ga-labeled Sgc8, the organs with strong to weak radioactive signals were bladder, kidney, heart, uterus, liver, spleen, gallbladder, large intestine and lung. Within 3 hours after drug administration, the clearance rate was fastest in heart, followed by uterus, kidney, and liver; the clearance rate was slower in spleen and gallbladder and were slowest in large intestine and lung. All of the 9 patients had abnormal radioactivity accumulation 4 hours after intravenous injection of 99mTc-labeled octreotide and the immunohistochemical staining results of biopsy tissues showed strong positive expression of SSTR2, indicating that 99mTc-labeled octreotide had good affinity and targeting to SSTR2. The safety evaluation showed that in Trail 1, one subject developed iodine-related hyperthyroidism one month after intravenously infusion of 131I-labeled mepuzumab, which returned to normal after 8 months of continuous monitoring without intervention. No adverse reactions occurred in other subjects. Conclusions:Radioisotope tracer technology can noninvasively, dynamically, and visually evaluate the pharmacokinetics, biological distribution, and targeting of biological drugs in human body. It has good safety and great application value in the clinical evaluation of biological drugs.

An amendment to this paper has been published and can be accessed via the original article.

目的:探讨核素心肌灌注扫描和全身骨扫描,患者受检时的剂量当量,了解这两项检查在日常工作中对医务人员及周围环境辐射剂量率的影响.方法:选择2015年1月～2018年1月在本院接受治疗的40例患者作为研究对象,使用Rad-60个人报警剂量仪对其进行测量,其中心肌灌注扫描20例,全身骨扫描20例,采集的同时将数字化个人剂量仪分别放置于受检者胸口及肝脏处,进行近距离测量,并且在距离患者1m处放置数字化个人剂量仪两个分别对准胸口及肝脏位置进行5min的远距离测量.结果:20例心肌灌注扫描患者近距离测量胸口辐射7～8μSv/h,肝脏辐射10～18μSv/h,1m之外,胸口及肝脏测量结果均为0.20例全身骨扫描患者近距离测量胸口辐射4～7μSv/h,膀胱5～8μSv/h,1m之外,胸口和膀胱均为0.结论:心肌灌注扫描和全身骨扫描的患者对于病房的医护人员及周围的人员不存在辐射安全隐患,对近距离摆位的工作人员存在一定的放射性辐射.

Background Osteoblastoma (OB) is an intermediate lesion, which makes the accurate preoperative diagnosis very important. 99m Tc-methylene diphosphonate ( 99m Tc-MDP) bone scan and SPECT/CT imaging were evaluated for their diagnostic value in spinal OB. Methods This study was a retrospective analysis of patients with spinal OB lesions confirmed by pathology and diagnosed with bone scan and SPECT/CT for preoperative diagnosis from January 2008 to December 2018. The uptake levels of OB on planar bone scan were divided into low, medium, and high groups by visual assessment referring to the uptake of the normal rib, spine, and bladder. X-ray, CT, MRI, bone scan, and SPECT/CT imaging of the patients were analyzed for characteristics summary. Results Twenty-five patients were diagnosed for spinal OB (17 males and 8 females with a proportion of 2.1:1), and the average age was 26.8 ± 10.8 years (range 5~59). There were 8 lesions located in the cervical, 6 in the thoracic, and 11 in the lumbar vertebrae. Twenty-four lesions involved posterior elements, especially the pedicles (14/25). Symptoms were predominantly painful with a duration of 18.3 ± 13.9 months (range 0.5~60 months). The lesion size ranged from 9 to 35 mm. All the lesions were low to high uptake in the planar bone scan, and the percentages of low to high levels were 1 (4%), 8 (32%), and 16 (64%) cases. Conclusions Spinal OB mainly involved the posterior area, and elderly patients should be considered as well. SPECT/CT combined the characteristics of bone uptake and anatomical features of bone tumors, proving its one-in-all diagnostic value for spinal OB and other osteogenic tumors.

MCC950 is a novel NLRP3 inflammasome inhibitor that possesses potent anti-inflammatory properties in acute myocardial infarction (AMI). However, the lack of noninvasive monitoring methods limits its potential clinical translation. Thus, we sought to investigate whether 18F-FDG PET imaging can monitor the therapeutic effects of MCC950 in an AMI murine model. C57BL/6 mice were used to generate an AMI model. MCC950 or sterile saline was intraperitoneally administered 1 hour after surgery and then daily for 7 consecutive days. 18F-FDG PET (inflammation) imaging was used to monitor inflammatory changes on days 3 and 5. Immunohistochemistry and Western blot were used to detect inflammatory markers and to confirm the PET imaging results. 18F-FDG PET (viability) imaging was used to quantitate the viability defect expansion on days 7 and 28. Cardiac ultrasound and survival analyses were performed to evaluate the cardiac function and survival rate. Adverse remodeling was determined by Wheat Germ Agglutinin (WGA) and Masson trichrome staining. The FDG-PET (inflammation) imaging revealed that MCC950 treatment led to lower 18F-FDG inflammatory uptakes, at the infarct region, on days 3 and 5 when compared to the MI group. The decreased M1 macrophages and neutrophils infiltration and the remission of the NLRP3/IL-1β pathway, confirmed the FDG-PET (inflammation) imaging results. The FDG-PET (viability) imaging revealed that MCC950 significantly decreased the expansion of the viability defect, demonstrating its myocardial preservation effects. The acute FDG-PET (inflammation) signal positively correlated with the late viability defect and with the reduction in the left ventricular ejection fraction (LVEF). Additionally, the alleviated adverse remodeling and the improved survival rate further support the anti-inflammatory efficiency of MCC950 in AMI. Using 18F-FDG PET imaging, we noninvasively demonstrated the therapeutic effects of MCC950 in AMI and showed that 18F-FDG PET imaging holds promising application potentials in MCC950’s clinical translation.

PURPOSE:The high false positive rate (FPR) of 18F-FDG PET/CT in lung cancer screening represents a severe challenge for clinical decision-making. This study aimed to develop a clinical-translatable radiomics nomogram for reducing the FPR of PET/CT in lung cancer diagnosis, and to determine the impact of integrating manual diagnosis to the performance of the radiomics nomogram.METHODS:Among 3,947 18F-FDG PET/CT-screened patients with lung lesion, 157 malignant and 111 benign patients were retrospectively enrolled and divided into training and test cohorts. The data of manual diagnosis were recorded. A total of 4,338 features were extracted from CT, thin-section CT, PET and PET/CT, and the four radiomics signatures (RS) were then generated by LASSO method. Radiomics prediction nomogram integrating imaging-based RS and manual diagnosis was developed using multivariable logistic regression. The performances of RS and prediction nomograms were independently validated through key discrimination index and clinical benefit.RESULTS:The FPR of manual diagnosis was found to be 30.6%. Among the four RS, PET/CT RS exhibited the best performance. By integrating manual diagnosis, the hybrid nomogram integrating PET/CT RS and manual diagnosis demonstrated lowest FPR and highest area under curve (AUC) and Youden index (YI) in both training and test cohorts (FPR: 5.4% and 9.1%, AUC: 0.98 and 0.92, YI: 85.8% and 75.5%, respectively). This hybrid nomogram respectively corrected 78.6% and 37.5% among FPR cases produced by PET/CT RS, without significantly sacrificing its sensitivity. The net benefit of hybrid nomogram appeared highest at <85% threshold probability.CONCLUSION:The established hybrid nomogram integrating PET/CT RS and manual diagnosis can significantly reduce FPR, improve diagnostic accuracy and enhance clinical benefit compared to manual diagnosis. By integrating manual diagnosis, the performance of this hybrid nomogram is superior to PET/CT RS, indicating the importance of clinicians' judgement as an essential information source for improving radiomics diagnostic approaches.

Adenosine receptors (ARs) are a class of purinergic G-protein-coupled receptors (GPCRs). Extracellular adenosine is a pivotal regulation molecule that adjusts physiological function through the interaction with four ARs: A1R, A2AR, A2BR, and A3R. Alterations of ARs function and expression have been studied in neurological diseases (epilepsy, Alzheimer’s disease, and Parkinson’s disease), cardiovascular diseases, cancer, and inflammation and autoimmune diseases. A series of Positron Emission Tomography (PET) probes for imaging ARs have been developed. The PET imaging probes have provided valuable information for diagnosis and therapy of diseases related to alterations of ARs expression. This review presents a concise overview of various ARs-targeted radioligands for PET imaging in diseases. The most recent advances in PET imaging studies by using ARs-targeted probes are briefly summarized.

Objective To compare the diagnostic efficacy of 68Ga-prostate specific membrane antigen (PSMA)-617 PET/CT and multi-parameter MRI for primary prostate cancer.Methods From June 2017 to November 2017,24 patients (age (67.6±7.0) years) with suspected prostate cancer were prospectively enrolled.All patients underwent 68Ga-PSMA-617 PET/CT and multi-parameter MRI.Pathological diagnosis was considered as the gold standard.The diagnostic efficacy of the two methods was analyzed and the difference was evaluated by receiver operating characteristic (ROC) curve analysis(Z test).Results Based on the puncture biopsy and/or excision biopsy,18 patients were diagnosed as prostate cancer and 6 patients were diagnosed as benign diseases.According to the five-zone analysis for the prostate (24 patients with 120 zones),48 and 56 zones were detected accurately in prostate cancer patients by PET/CT and multi-parameter MRI respectively,which was 54 and 41 for benign patients.The cut-off value of maximum standardized uptake value (SUVmax) in 68Ga-PSMA-617 PET/CT for diagnosing prostate cancer was 4.85,the area under curve (AUC),sensitivity,specificity,positive predictive value,negative predictive value,accuracy and Youden index were 0.890,75.00％ (48/64),96.43％ (54/56),96.00％ (48/50),77.14％ (54/70),85.00％(102/120),71.43％ respectively for prostate cancer by PET/CT,and 0.837,87.50％(56/64),73.21％ (41/56),78.87％ (56/71),83.67％ (41/49),80.83％ (97/120) and 60.71％ respectively by multi-parameter MRI.The difference of AUC was statistically significant (Z=2.82,P＜0.01).Conclusions The diagnostic accuracy of 68Ga-PSMA-617 PET/CT imaging for prostate cancer is higher than that of multi-parameter MRI.Both modalities have high diagnostic efficiency and can be used scientifically as complementary.

The clinical applications of the quantitative single photon emission computed tomography (SPECT)/computed tomography (CT) are being expanded to a variety of fields of nuclear medicine. However, clinical application of quantitative SPECT/CT for the evaluation of Graves’ disease (GD) still needs further investigation. Our aim was to investigate the feasibility of standard uptake value (SUV) of the thyroid for the clinical diagnosis and evaluation of GD. In this prospective multicenter study, 116 patients diagnosed with GD (Graves group) and 74 healthy volunteers (control group) were enrolled from 8 different hospitals. All patients underwent technetium pertechnetate (TcO99m4-) SPECT/CT imaging with Q.Metrix quantitative software and 24-hour thyroid radioactive iodine uptake (24h-RAIU) test. The SUVmax and SUVmean in Graves group were significantly higher than those of control group (P<0.01). Cut-off values of SUVmax and SUVmean to predict GD were 231.425 and 116.66 by ROC curves, respectively. The SUVmax and SUVmean in Graves patients were significantly related to serum thyroxine level with correlation coefficient of 0.493 and 0.512 for FT3 and 0.449 and 0.464 for FT4, respectively (all P<0.01). Additionally, the SUVmax and SUVmean in GD positively correlated with 24h-RAIU with a coefficient of 0.832 and 0.830, respectively (P<0.01). The volumes determined by Q.Metrix (35.65 ± 20.56ml) of 72 subjects also positively correlated with that from ultrasound (36.67 ± 21.00ml) with a coefficient of 0.927 (P<0.01). SUV measurements derived from thyroid SPECT/CT may be useful for the clinical diagnosis and evaluation of GD.