Hepatic Cavernous Hemangioma Mimicking Malignancy on 18 F-FDG PET/CT Imaging.

ABSTRACT: A 65-year-old woman was referred to our hospital because of a liver lesion revealed by ultrasound and CT in an outside institution. 18 F-FDG PET/CT images revealed an FDG-avid lesion in the left lateral lobe of the liver. Malignancy cannot be excluded. A subsequent resection was performed to remove the lesion. Postoperative pathology was hepatic cavernous hemangioma. This case suggests that PET/CT findings of FDG-avid hepatic cavernous hemangioma could mimic malignancy.

Dynamic PET/CT scan of 68Ga-FAPI-04 for the optimal acquisition time in suspected malignant hepatic cancer patients.

PURPOSE: Dynamic PET/CT scan of 68Ga-FAPI-04 in patients with suspected malignant hepatic lesions were retrospectively analyzed to find the optimal acquisition time with better lesion detection rate. METHODS: Twenty-two patients with lesions confirmed by CT or MRI were performed with dynamic 68Ga-FAPI-04 PET/CT scan. Tracer uptake of lesions and normal organs at different time points were analyzed. Standardized uptake value (SUV) and tumor-to-background (TBR) were calculated based on the quantification of images. RESULTS: SUV of normal organs decreased rapidly from 10 to 30 min and decreased gradually from 30 to 60 min. Besides, the uterus showed a particularly high uptake in all patients (12.62 ± 4.58 at 10 min p.i., 12.04 ± 3.99 at 30 min p.i., 10.92 ± 2.38 at 60 min p.i.). SUV of lesions decreased gradually, while TBR increased from 10- to 60-min post-injection. Visual analysis verified a comparable lesion detectability of 30 min and 60 min with images of 10 min showing a decreased lesion detection number. CONCLUSION: This study revealed that similar detection rates were achieved at both 30 and 60 min, suggesting a static scan at 30 min to be appropriate in the clinic. Besides, although with high lesion uptake, early 68Ga-FAPI-04 PET imaging at 10 min after tracer injection could cause missed lesion detection.

Characterization of myocardial oxidative metabolism and myocardial external efficiency in high-risk alcohol cardiotoxicity and alcoholic cardiomyopathy via dynamic 11C-Acetate positron emission tomography.

INTRODUCTION: The purpose of this study was to evaluate subjects with high-risk alcohol cardiotoxicity and patients with alcoholic cardiomyopathy (ACM) via dynamic 11C-Acetate positron emission tomography (PET) imaging as a myocardial oxidative metabolic probe. METHODS AND RESULTS: We recruited 37 subjects with chronic alcohol consumption [18 with moderate consumption (MC), 19 with heavy consumption (HC)], 5 ACM patients, and 12 healthy controls to receive dynamic 11C-Acetate PET scans. PET imaging data were analyzed to calculate kinetic parameters (e.g., Kmono, K1 and k2) based on the mono-exponential and one-tissue compartmental models. Myocardial oxygen consumption (MVO2) and myocardial external efficiency (MEE) were then derived from these kinetic parameters. MVO2 was significantly lowered in the HC group and in ACM patients (0.121± 0.018 and 0.111 ± 0.017 mL·g-1·min-1, respectively) compared with those in healthy controls and MC subjects (0.144 ± 0.023 and 0.146 ± 0.027 mL·g-1·min-1, respectively; P < .01). MEE was significantly reduced in ACM patients (13.0% ± 4.3%) compared with those of healthy controls (22.4% ± 4.6%, P < .01), MC subjects (20.1% ± 4.5%, P < .05), and HC subjects (22.3% ± 4.5%, P < .001). CONCLUSION: Functional assessment via dynamic 11C-Acetate PET imaging may represent a clinically feasible probe for identifying cohorts with high-risk cardiotoxicity due to addictive alcohol consumption and ACM.

Feasibility of In Vivo Imaging of Fibroblast Activation Protein in Human Arterial Walls.

Increased expression of fibroblast-activating protein (FAP) in fibrous caps may contribute to progression of atherosclerotic plaques. Methods: Forty-one patients who underwent 68Ga-conjugated quinoline-based FAP inhibitor (68Ga-FAPI-04) PET/CT for noncardiovascular indications were retrospectively analyzed. Correlations were assessed between the uptake of 68Ga-FAPI-04 in large arterial walls (SUVmax and target-to-background ratio, TBR) and degree of calcification and cardiovascular risk factors. Results: Focal arterial uptake of 68Ga-FAPI-04 or calcification was detected in 1,177 arterial segments in all 41 patients. TBR was negatively correlated with the degree of calcification (Hounsfield units) (r = -0.27, P < 0.01). Mean TBR in higher-risk patients was greater than in lower-risk patients (2.2 ± 0.3 vs. 1.8 ± 0.3, P < 0.01). Immunohistochemical labeling of carotid plaques exhibited prominent FAP expression in a thin fibrous cap and moderate FAP expression in a thick cap. Conclusion:68Ga-FAPI-04 PET/CT might have potential for imaging fibroblastic activation in the arterial wall.

A methodological investigation of healthy tissue, hepatocellular carcinoma, and other lesions with dynamic 68Ga-FAPI-04 PET/CT imaging.

BACKGROUND: The study aimed to establish a 68Ga-FAPI-04 kinetic model in hepatic lesions, to determine the potential role of kinetic parameters in the differentiation of hepatocellular carcinoma (HCC) from non-HCC lesions. MATERIAL AND METHODS: Time activity curves (TACs) were extracted from seven HCC lesions and five non-HCC lesions obtained from 68Ga-FAPI-04 dynamic positron emission tomography (PET) scans of eight patients. Three kinetic models were applied to the TACs, using image-derived hepatic artery and/or portal vein as input functions. The maximum standardized uptake value (SUVmax) was taken for the lesions, the hepatic artery, and for the portal veins-the mean SUV for all healthy regions. The optimum model was chosen after applying the Schwartz information criteria to the TACs, differences in model parameters between HCC, non-HCC lesions, and healthy tissue were evaluated with the ANOVA test. RESULTS: A reversible two-tissue compartment model using both the arterial as well as venous input function was most preferred and showed significant differences in the kinetic parameters VND, VT, and BPND between HCC, non-HCC lesions, and healthy regions (p < 0.01). CONCLUSION: Several model parameters derived from a two-tissue compartment kinetic model with two image-derived input function from vein and aorta and using SUVmax allow a differentiation between HCC and non-HCC lesions, obtained from dynamically performed PET scans using FAPI.

Scintigraphic Imaging of Neovascularization With 99mTc-3PRGD2 for Evaluating Early Response to Endostar Involved Therapies on Pancreatic Cancer Xenografts In Vivo.

Background: Molecular imaging targeting angiogenesis can specifically monitor the early therapeutic effect of antiangiogenesis therapy. We explore the predictive values of an integrin αvß3-targeted tracer, 99mTc-PEG4-E[PEG4-c(RGDfK)]2 (99mTc-3PRGD2), for monitoring the efficacy of Endostar antiangiogenic therapy and chemotherapy in animal models. Methods: The pancreatic cancer xenograft mice were randomly divided into four groups, with seven animals in each group and treated in different groups with 10 mg/kg/day of Endostar, 10 mg/kg/day of gemcitabine, 10 mg/kg/day of Endostar +10 mg/kg/day of gemcitabine at the same time, and the control group with 0.9% saline (0.1 ml/day). 99mTc-3PRGD2 scintigraphic imaging was carried out to monitor therapeutic effects. Microvessel density (MVD) was measured using immunohistochemical staining of the tumor tissues. The region of interest (ROI) of tumor (T) and contralateral corresponding site (NT) was delineated, and the ratio of radioactivity (T/NT) was calculated. Two-way repeated-measure analysis of variance (ANOVA) was used to assess differences between treatment groups. Results: Tumor growth was significantly lower in treatment groups than that in the control group (p < 0.05), and the differences were noted on day 28 posttreatment. The differences of 99mTc-3PRGD2 uptakes were observed between the control group and Endostar group (p = 0.033) and the combined treatment group (p < 0.01) on day 7 posttreatment and on day 14 posttreatment between the control group and gemcitabine group (p < 0.01). The accumulation of 99mTc-3PRGD2 was significantly correlated with MVD (r = 0.998, p = 0.002). Conclusion: With 99mTc-3PRGD2 scintigraphic imaging, the tumor response to antiangiogenic therapy, chemotherapy, and the combined treatment can be observed at an early stage of the treatments, much earlier than the tumor volume change. It provides new opportunities for developing individualized therapies and dose optimization.

Fibroblast imaging of hepatic carcinoma with 68Ga-FAPI-04 PET/CT: a pilot study in patients with suspected hepatic nodules.

PURPOSE: 68Ga-FAPI-04 is a rapidly evolving PET tracer for whole-body imaging in a variety of cancers. We aimed to evaluate the diagnostic performance of 68Ga-FAPI-04 for detecting and characterizing hepatic nodules in patients with suspected carcinoma. METHODS: Twenty-five patients showing suspicious hepatic lesions for malignancy underwent 68Ga-FAPI-04 PET. The maximum and mean standardised uptake values (SUVmax, SUVmean) were measured for all detected lesions and normal hepatic tissues, respectively. The target-to-background ratio (TBR) was calculated by dividing the lesion SUVmax with the SUVmean of non-tumour liver tissue. Lesion uptake value was correlated with the in vitro hepatic FAP expression determined by immunohistochemistry (IHC). RESULTS: In total, 17 patients who underwent surgery or biopsy were recruited for the final analysis. A total of 28 intrahepatic malignant lesions were detected in 16 patients; the mean SUVmax was 8.36 ± 4.21 (range 2.21 to 15.86), and mean TBR was 13.15 ± 9.48 (range 2.79 to 38.12) in all detected lesions (n = 28). One benign patient showed negligible hepatic uptake (SUVmax = 0.47), whereas 75% of the primary intrahepatic hepatocellular carcinoma (HCC) lesions (n = 6) showed prominent FAP expression, 12.5% of the lesions (n = 1) showed moderate expression in stromal cells, and one showed negligible expression. CONCLUSIONS: 68Ga-FAPI-04 showed high sensitivity in detecting hepatic malignancies, particularly in poorly differentiated forms with concordantly elevated FAP expression.

Comparison of PET imaging of activated fibroblasts and 18F-FDG for diagnosis of primary hepatic tumours: a prospective pilot study.

PURPOSE: This study aimed to compare the performance of 68Ga-labelled fibroblast activating protein inhibitor (FAPI) PET and 18F-FDG PET for imaging of hepatic tumours. METHODS: We prospectively assessed 20 patients with suspected intrahepatic lesions. Tumour radiological features, pathology, or follow-up examinations were assessed as ground truth in correlation with PET scans. Semiquantitative analysis was additionally performed by measuring the standardised uptake value (SUV). Tumour-to-liver background ratios (TBR) were calculated and compared between 68Ga-FAPI PET and 18F-FDG PET. FAPI expression was assessed by immunochemistry in samples obtained from 7 patients with hepatocellular carcinomas (HCC)/intrahepatic cholangiocarcinoma (ICC) or granulomas. RESULTS: Primary intrahepatic tumours, including 16 HCC in 14 patients and 4 ICC in 3 patients with extrahepatic metastases, were determined by histology (n = 14) and clinical examinations (n = 3). Based on visual analysis, 17 patients presented elevated 68Ga-FAPI uptake (sensitivity: 100%, specificity: 100%), while 7 patients presented 18F-FDG avid tumours (sensitivity: 58.8%, specificity: 100%). 68Ga-FAPI PET/CT identified 17 extrahepatic metastases vs. 13 in 18F-FDG PET/CT in 2 ICC patients. Three benign liver nodules in three patients showed negligible uptake in dual-PET scans. The SUVmax_HCC = 8.47 ± 4.06 and TBRmax_HCC = 7.13 ± 5.52, and SUVmax_ICC = 14.14 ± 2.20 TBRmax_ICC = 26.46 ± 4.94 in 68Ga-FAPI-04 PET/CT were significantly higher than the 18F-FDG uptake presenting SUVmax_HCC = 4.86 ± 3.58 and TBRmax_HCC = 2.39 ± 2.21, and SUVmax_ICC = 9.19 ± 3.60 and TBRmax_ICC = 2.39 ± 2.21 (all p values < 0.05). ICC patients showed higher levels of FAPI uptake in the primary hepatic lesions compared to extrahepatic metastases, TBRmax_ICC = 15.18 ± 5.80 (p = 0.04). CONCLUSIONS: 68Ga-FAPI PET-CT has superior potential in the detection of primary hepatic malignancy compared to 18F-FDG.

Myocardial tissue and metabolism characterization in men with alcohol consumption by cardiovascular magnetic resonance and 11C-acetate PET/CT.

BACKGROUND: Chronic alcohol consumption initially leads to asymptomatic left ventricular dysfunction, but can result in myocardial impairment and heart failure if ongoing. This study sought to characterize myocardial tissues and oxidative metabolism in asymptomatic subjects with chronic alcohol consumption by quantitative cardiovascular magnetic resonance (CMR) and 11C-acetate positron emission tomography (PET)/computed tomography (CT). METHODS: Thirty-four male subjects (48.8 ± 9.1 years) with alcohol consumption > 28 g/day for > 10 years and 35 age-matched healthy male subjects (49.5 ± 9.7 years) underwent CMR and 11C-acetate PET/CT. Native and post T1 values and extracellular volume (ECV) from CMR and Kmono and K1 from PET imaging were measured. Quantitative measurements by CMR and PET imaging were compared between subjects with moderate to heavy alcohol consumption and healthy controls, and their correlations were also analyzed. RESULTS: Compared to healthy controls, subjects with alcohol consumption showed significantly shorter native T1 (1133 ± 65 ms vs. 1186 ± 31 ms, p < 0.001) and post T1 (477 ± 42 ms vs. 501 ± 38 ms, p = 0.008) values, greater ECV (28.2 ± 2.2% vs. 26.9 ± 1.3%, p = 0.003), marginally lower Kmono (57.6 ± 12.1 min- 1 × 10- 3 vs. 63.0 ± 11.7 min- 1 × 10- 3, p = 0.055), and similar K1 (0.82 ± 0.13 min- 1 vs. 0.83 ± 0.15 min- 1, p = 0.548) after adjusting for confounding factors. There were no significant differences in CMR measurements and K1 between subjects with heavy and moderate alcohol consumption (all p > 0.05). In contrast, subjects with heavy alcohol consumption showed significantly lower Kmono values compared to those with moderate alcohol consumption (52.9 ± 12.1 min- 1 × 10- 3 vs. 63.7 ± 9.2 min- 1 × 10- 3, p = 0.012). Strong and moderate correlations were found between K1 and ECV in healthy controls (r = 0.689, p = 0.013) and subjects with moderate alcohol consumption (r = 0.518, p = 0.048), respectively. CONCLUSION: Asymptomatic men with heavy alcohol consumption have detectable structural and metabolic changes in myocardium on CMR and 11C-acetate PET/CT. Compared with quantitative CMR, 11C-acetate PET/CT imaging may be more sensitive for detecting differences in myocardial damage among subjects with moderate to heavy alcohol consumption.

Three patterns of osteoarticular involvement in SAPHO syndrome: a cluster analysis based on whole body bone scintigraphy of 157 patients.

OBJECTIVES: To explore the patterns of osteoarticular involvement in SAPHO syndrome. METHODS: Baseline clinical characteristics and imaging data of 99mTc-MDP whole-body bone scintigraphy (WBBS) were collected from 157 out of 164 patients diagnosed with SAPHO syndrome. The twelve most frequently involved osteoarticular sites were analysed by hierarchical cluster analysis with the Ward minimum-variance method. RESULTS: Three distinctive patterns of osteoarticular involvement were identified: the spinal type (70 patients, 44.6%), with predominantly thoracic, lumbar or sacral vertebral lesions; the costal type (52 patients, 33.1%), with lesions of anterior ribs, particularly the first ribs; and the sternoclavicular type (35 patients, 22.3%), with predominantly sternal and bilateral sternoclavicular lesions, characterized by the typical bullhead sign. Notably, a total of 77 (49%) patients exhibited lesions of ribs on WBBS, of which 61.3% involved the first ribs. Interestingly, patients of spinal type were older at onset of cutaneous manifestations than those of sternoclavicular type (P = 0.036) and costal type (P = 0.035). The disease course was remarkably longer in sternoclavicular type than costal type (P = 0.001) and spinal type (P < 0.001). CONCLUSION: The osteoarticular involvement in SAPHO syndrome can be categorized as three distinct patterns with different corresponding clinical features. The costal involvement in SAPHO syndrome, which was under-recognized previously, may define a distinct sub-type of the disease.

99mTc-HYNIC-TOC in the Evaluation of Recurrent Tumor-Induced Osteomalacia.

PURPOSE: Tumor-induced osteomalacia (TIO) is rare paraneoplastic disorder generally caused by small benign neoplasm. Somatostatin receptor imaging has emerged as imaging of the choice in the localization of the causative tumors in new patients with clinical diagnosis of TIO. An accurate localization of the causative tumor using somatostatin receptor imaging followed by successful surgical removal offers cure of the disease. In small percentage of the patients, however, there can be recurrent disease after the surgery. In this retrospective investigation, we tried to assess whether somatostatin receptor imaging using Tc-HYNIC-TOC (Tc-hydrazinonicotinyl-Tyr3-octreotide) is also useful in patients with recurrent TIO after initial successful surgery. METHODS: The images of Tc-HYNIC-TOC images and clinical charts of total 18 patients with suspected recurrent TIO were retrospectively reviewed. The image findings were compared with the clinical chart, which include clinical follow-up and subsequent imaging and surgery. RESULTS: Among all 18 patients, Tc-HYNIC-TOC imaging results were negative in 5 of them. Among these 5 patients with negative imaging study, the causes of recurrent symptoms and hypophosphatemia in 3 patients were eventually found unrelated to TIO. Tc-HYNIC-TOC successfully identified either recurrent causative tumors in the same location (n = 10) or different causative tumor in other locations (n = 3) in 13 patients, which rendered a sensitivity of 86.7% (13 of 15). CONCLUSIONS: The efficacy of Tc-HYNIC-TOC imaging in the evaluation of patients with potential recurrent TIO is compatible to that with new patients who never received surgical resection for the culprit tumors. It can play an important role in known TIO patients who were suspected to have recurrent disease.

F-18 FDG PET/CT in 26 patients with SAPHO syndrome: a new vision of clinical and bone scintigraphy correlation.

BACKGROUNDS: Whole-body bone scintigraphy (WBBS) and MRI are widely used in assessment of patients with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome. However, the value of F-18 fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) in SAPHO syndrome was unclear. The aim of this study was to characterize the manifestation of SAPHO syndrome on 18F-FDG PET/CT and explore its relationship with clinical symptoms and WBBS. METHODS: Twenty-six patients who suffered from SAPHO syndrome and had undergone whole-body 18F-FDG PET/CT were recruited in Peking Union Medical College Hospital from 2004 to 2016. Clinical manifestations and laboratory findings were recorded for all patients. Imaging data on 18F-FDG PET/CT and WBBS were collected and analyzed retrospectively. RESULTS: All the 26 patients (20 females and 6 males) exhibited skeletal abnormalities on 18F-FDG PET/CT. Multiple skeletal lesions affecting the anterior chest wall or spine with low to moderate 18F-FDG uptake and coexistence of osteolysis and osteosclerosis presented as the typical features of SAPHO syndrome. Sixteen (61.5%) patients had abnormal 18F-FDG uptake outside the osteoarticular system. PET scan had moderate to substantial agreement with CT and WBBS in revealing lesions in the anterior chest wall and axial skeleton. Nonetheless, the correlation between increased 18F-FDG uptake and clinical symptoms was weak. CONCLUSIONS: SAPHO syndrome exhibits characteristic features on 18F-FDG PET/CT. It showed comparable capacity in revealing skeletal lesions with bone scintigraphy.

Comparison among Reconstruction Algorithms for Quantitative Analysis of 11C-Acetate Cardiac PET Imaging.

Objective: Kinetic modeling of dynamic 11C-acetate PET imaging provides quantitative information for myocardium assessment. The quality and quantitation of PET images are known to be dependent on PET reconstruction methods. This study aims to investigate the impacts of reconstruction algorithms on the quantitative analysis of dynamic 11C-acetate cardiac PET imaging. Methods: Suspected alcoholic cardiomyopathy patients (N = 24) underwent 11C-acetate dynamic PET imaging after low dose CT scan. PET images were reconstructed using four algorithms: filtered backprojection (FBP), ordered subsets expectation maximization (OSEM), OSEM with time-of-flight (TOF), and OSEM with both time-of-flight and point-spread-function (TPSF). Standardized uptake values (SUVs) at different time points were compared among images reconstructed using the four algorithms. Time-activity curves (TACs) in myocardium and blood pools of ventricles were generated from the dynamic image series. Kinetic parameters K1 and k2 were derived using a 1-tissue-compartment model for kinetic modeling of cardiac flow from 11C-acetate PET images. Results: Significant image quality improvement was found in the images reconstructed using iterative OSEM-type algorithms (OSME, TOF, and TPSF) compared with FBP. However, no statistical differences in SUVs were observed among the four reconstruction methods at the selected time points. Kinetic parameters K1 and k2 also exhibited no statistical difference among the four reconstruction algorithms in terms of mean value and standard deviation. However, for the correlation analysis, OSEM reconstruction presented relatively higher residual in correlation with FBP reconstruction compared with TOF and TPSF reconstruction, and TOF and TPSF reconstruction were highly correlated with each other. Conclusion: All the tested reconstruction algorithms performed similarly for quantitative analysis of 11C-acetate cardiac PET imaging. TOF and TPSF yielded highly consistent kinetic parameter results with superior image quality compared with FBP. OSEM was relatively less reliable. Both TOF and TPSF were recommended for cardiac 11C-acetate kinetic analysis.

Primary Pericardial Angiosarcoma Shown on FDG PET/CT.

A 63-year-old woman had persistent bloody pericardial effusion. Tuberculous pericarditis was initially suspected, but empirical antituberculosis therapy was futile. FDG PET/CT study revealed abnormal FDG activity in multiple parts of the pericardium, especially along with aorta and main pulmonary artery, and in the left atrium. However, there was no abnormal activity in other parts of the body. Histopathologic examination revealed primary pericardial angiosarcoma.

Validation of glomerular filtration rate-estimating equations in Chinese children.

BACKGROUND: Glomerular filtration rate (GFR) is essential for renal function evaluation and classification of chronic kidney disease (CKD), while the reference method in children are cumbersome. In the Chinese children, there was no data about GFR measured through plasma or renal clearance of the exogenous markers, and therefore no validated GFR-estimating tools in this population. METHODS: We measured GFR with double-sample plasma clearance of 99mTc-DTPA (mGFR) in 87 hospitalized children with renal injury. Using mGFR as the golden standard, we evaluate the efficiency of four different GFR estimation equations (the original and update Schwartz equation, the Filler equation, the CKiD equation) by statistical parameters of correlation, precision and accuracy. RESULTS: In our population, mGFR was 97.0± 31.9 mL/min/1.73m2. The updated Schwartz equation, the Filler equation and the CKiD equation, produced eGFR with strong correlation with mGFR, strong explanation capacity of variance in mGFR, small bias, satisfactory performance in Bland-Altman analysis, high intra-class correlation coefficients, high ratio of eGFR within mGFR±10% and eGFR within mGFR±30%, good agreement in CKD staging between eGFR and mGFR. The original Schwartz equation produced eGFR with large bias, poor precision and accuracy. CONCLUSION: The validated equations to estimate GFR in our patients are the updated Schwartz equation, which is simple for bedside use, the Filler equation and the CKiD equation, which provide more accurate eGFR. The original Schwartz equation should not be applied to estimate GFR in Chinese children with kidney injuries.

Primary Neuroendocrine Carcinoma of the Kidney on FDG PET/CT.

A 28-year-old woman presented gradually worsening intermittent right groin pain for 10 months. FDG PET/CT was performed to evaluate the suspected renal malignancy. The images demonstrated a large hypermetabolic tumor occupying the entire right kidney. Pathological examination demonstrated a primary neuroendocrine carcinoma of the kidney.

Integrin Imaging with 99mTc-3PRGD2 SPECT/CT Shows High Specificity in the Diagnosis of Lymph Node Metastasis from Non-Small Cell Lung Cancer.

Purpose To evaluate an integrin imaging approach based on single photon emission computed tomography (SPECT)/computed tomography (CT) by using technetium 99m (99mTc)-dimeric cyclic arginine-glycine-aspartic acid (RGD) peptides with three polyethylene glycol spacers (3PRGD2) as the tracer to target the integrin αvß3 expression in lung cancer and lymph node metastasis. Materials and Methods With ethics committee approval and written informed consent, 65 patients (41 male, 24 female; mean age, 60 years ± 11 [standard deviation]) with suspicious lung lesions were recruited with informed consent. The patients underwent both 99mTc-3PRGD2 SPECT/CT and fluorine 18 (18F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT within 1 week. Finally, 65 lung lesions in 53 patients were pathologically diagnosed as non-small cell lung cancer (NSCLC) and 14 lung lesions in 12 patients were benign. Per-region analysis of lymph nodes included 248 regions with metastasis and 56 negative regions. Twenty specimens from the removed lung lesions or lymph nodes were stained with integrin αvß3, CD34, and Ki-67 to correlate with the image findings. Receiver operating characteristic curve, z statistics, McNemar test, and χ2 analysis were used to compare the diagnostic performance of the two imaging methods. Results 99mTc-3PRGD2 SPECT/CT was found to be more specific than 18F-FDG PET/CT in the per-region diagnosis of lymph node metastasis (specificity, 94.6% vs 75.0%; P = .008) when the sensitivity of the two methods was comparable (88.3% vs 90.7%; P = .557). There was no significant difference between the two methods in the per-lesion diagnosis of lung tumor (z = 0.82, P = .410). The accumulation level of 99mTc-3PRGD2 was found in positive correlation with the integrin αvß3 expression (r = 0.84, P = .001) and microvessel density (r = 0.63, P = .011) in the tumors. Conclusion 99mTc-3PRGD2 SPECT/CT shows high specificity in the diagnosis of lymph node metastasis from NSCLC, which may benefit surgical decision making for the patients. © RSNA, 2016.

Application of plasma clearance of iohexol in evaluating renal function in chinese children with chronic kidney disease.

OBJECTIVE: To evaluate the accuracy of plasma clearance of iohexol (PCio) for glomerular filtration rate (GFR) measurement in Chinese children with chronic kidney disease (CKD) and assess the feasibility of single-blood-sample method or dried capillary blood spots in determining the PCio. METHODS: Totally 45 CKD children were included,in whom the (99m) Technetium-diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) plasma clearance and iohexol plasma clearance were simultaneously determined. Blood samples were obtained 2,4,and 5 hours after injection. In addition, we also evaluated the efficacy of single blood sample method and dried blood spots method in iohexol plasma clearance. RESULTS: Forty-five CKD children completed the iohexol plasma clearance and thirty-six children completed the (99m)Tc-DTPA plasma clearance at the same time among them. Thirteen children finished the iohexol dried blood spot clearance. The correlation coefficient between (99m)Tc-DTPA plasma clearance and iohexol plasma clearance was 0.941 and the bias was (6.53 ± 11.6) ml/ (min·1.73 m²), and the intraclass correlation coefficient (ICC) was high (ICC=0.947). The correlation between iohexol single-sample plasma clearance and double samples was also strong (r=0.958), with the bias being (4.26 ± 9.06)ml/(min·1.73 m²) and the ICC being 0.970. The iohexol clearance by dried blood spots showed a good correlation with the serum iohexol clearance (r=0.950), with the bias still being small [(0.48 ± 10.89)ml/(min·1.73 m²)]. CONCLUSIONS: Iohexol plasma clearance has satisfactory agreement with (99m)Tc-DTPA plasma clearance and can be used as an ideal method to measure GFR in CKD children. The single-sample method and dried blood spots method make iohexol plasma clearance more convenient and practical.

Clinical applications of 18F-FDG PET/CT in monitoring anti-cancer therapies.

Cancer is becoming the largest threat to human health. Apart from classical anti-cancer therapies such as surgery, chemotherapies, and radiotherapy, many new therapies are being developed or translated into clinical use. These therapies include various neoadjuvant chemotherapies, minimally invasive treatments, and molecular-targeted therapies. However, none of these methods benefit all patients because treatment should be personalized according to the response of each patient. A futile therapy makes a patient miss the optimum time for treatment and increases the medical burden to the society. Thus, a great challenge is encountered in monitoring such therapies. Classical methods based on anatomical changes such as computed tomography (CT) and magnetic resonance imaging (MRI) have well-known limitations in early response evaluation. Positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) as tracer is a promising method especially when integrated with CT or MRI in one system. This article reviews the current status of monitoring anti-cancer therapies, including the evolution of evaluation criteria from the World Health Organization to the Response Evaluation Criteria in Solid Tumor and the PET Response Criteria in Solid Tumor. The advantages of 18F-FDG PET/CT for response evaluation are analyzed in various malignant tumors, and the pertinent weaknesses are discussed. Finally, several future directions in monitoring anti-cancer therapies are prospected.