2-deoxyglucose Research Articles

Predictive value of 18F-FDG PET/CT related metabolic parameters for Kras mutation in colorectal cancer patients

Objective To explore the predictive value of 18F-fluorodeoxyglucose (FDG) PET/CT related metabolic parameters for Kras mutation in colorectal cancer (CRC) patients. Methods Retrospective analysis was conducted in 150 patients (105 males, 45 females, median age: 63 years) with CRC who underwent 18F-FDG PET/CT in Changhai Hospital of Navy Medical University between November 2011 and August 2017. The primary tumors were removed by surgery and patients received genetic testing within 1 month after PET/CT. 18F-FDG PET/CT related metabolic parameters were measured, including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV; including MTV2.5, MTV20%, MTV30%, MTV40%, MTV50%), total lesion glycolysis (TLG; including TLG2.5, TLG20%, TLG30%, TLG40%, TLG50%). Logistic regression analysis and receiver operating characteristic (ROC) curve analysis were used to analyze the data. Results There were 78 Kras-mutated type patients and 72 wild-type patients. Logistic regression analysis showed that SUVmax (odds ratio (OR)=1.176, 95% CI: 1.043-1.327) and MTV2.5 (OR=1.125, 95% CI: 1.002-1.263) were predictors of Kras mutation. With SUVmax=15.5 and MTV2.5=23.79 cm3 as the cut-off value, the prediction accuracies of Kras mutation were 67.33%(101/150) and 65.33%(98/150), respectively. The accuracies of SUVmax and MTV2.5 for predicting Kras mutation were higher in recta or sigmoid colon cancers (70.79%(63/89) and 68.54%(61/89)). Conclusion SUVmax and MTV2.5 can predict Kras mutation in CRC patients, but there is a significant gap of predictive efficiency between PET/CT and gene detection. Key words: Colorectal neoplasms; Oncogenes; Mutation; Positron-emission tomography; Deoxyglucose

Imaging features of pediatric rhabdomyosarcoma on 18F-FDG PET/CT

Objective To summarize the 18F-fluorodeoxyglucose (FDG) PET/CT findings of pediatric rhabdomyosarcoma (RMS), and to explore the value of PET/CT in the diagnosis of RMS. Methods PET/CT images and clinical data of 29 RMS patients (15 males, 14 females, age range: 1-14 years) histopathologically confirmed from July 2011 to September 2017 were evaluated retrospectively. The imaging features were analyzed, and the maximum standardized uptake value (SUVmax) ratios of tumors to the liver (TLR) in different pathological types of RMS were calculated and compared. Mann-Whitney u test was used to analyze the data. Results There were 19 patients with embryonic RMS, 7 with alveolar RMS, and 3 with unknown types. The median SUVmax of primary lesion was 6.8(4.3, 8.9). There were no statistically significant differences in SUVmax (6.2(4.3, 8.8) vs 5.3(4.0, 9.0)) and TLR (3.6(2.6, 8.1) vs 3.0(2.2, 6.3)) between embryonic RMS and alveolar RMS (u values: 60.00 and 48.50, both P>0.05). PET/CT detected lymph nodes lesions with increased metabolism in 15 patients, lung lesions in 6 patients, bone or bone marrow lesions in 4 patients and breast involvement in 2 patients. Conclusion 18F-FDG PET/CT can indicate the extent and metabolic activity of RMS, thus providing information for clinical practice. Key words: Rhabdomyosarcoma; Child; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Predicative value of radiomics nomogram based on 18F-FDG PET/CT for the prognosis of patients with postoperative gastric carcinoma

Objective To investigate the clinical value of radiomics nomogram, which is established by 18F-fluorodeoxyglucose (FDG) PET/CT radiomics signature combined with clinical-pathologic risk factors, in predicting the prognosis of patients with postoperative gastric carcinoma. Methods 18F-FDG PET/CT data of 207 patients (143 males, 64 females, age range: 20-85 years) with postoperative gastric carcinoma from January 2008 to August 2015 was reviewed retrospectively. Patients were divided into training group (n=104) and validation group (n=103), and the clinicopathologic information and disease-free survival (DFS) data were acquired. Significant textural features were selected from PET/CT images, and radiomics score (RS) for individual patient was calculated based on the radiomics signatures. The relationship between RS and DFS was analyzed. Cox regression analysis was performed to determine the risk factors of DFS. The radiomics nomogram, obtained from combination of RS with clinicopathologic risk factors, was established and further evaluated in predictive value for recurrence or metastasis of postoperative gastric carcinoma, and the concordance index (C-index) was calculated. Results Cox regression analysis demonstrated that RS, tumor location, depth of invasion, lymph node metastasis, and distant metastasis were the significant risk factors for DFS (hazard ratios: 2.148-2.828, all P<0.05). The radiomics nomogram combined with RS and 4 clinicopathologic risk factors had a better prediction for the estimated DFS, comparing to RS alone. C-index of radiomics nomogram and RS were 0.830 and 0.700 in training group, and 0.776 and 0.681 in validation group, respectively. Conclusion Radiomics nomogram which is established by radiomics signatures and clinicopathologic risk factors may be better for predicting DFS of patients with postoperative gastric carcinoma. Key words: Stomach neoplasms; Prognosis; Positron-emission tomography; Tomography, X-ray computed; Nomograms; Deoxyglucose

Application of 18F-FDG PET/CT in IgG4-related disease

Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a new multi-organ immune-mediated disease, which was characterized by multiple organs involvement, high serum IgG4 concentrations and IgG4+ plasma cells infiltration. Early diagnosis is helpful for the treatment and prognosis evaluation. Imaging can provide important diagnostic bases for IgG4-RD, but conventional imaging methods are difficult to determine the overall involvement of the patient. 18F-fluorodeoxyglucose (FDG) PET/CT can display the changes of morphology and metabolism in involved organs, and can be used in the diagnosis, guidance of biopsy, therapeutic response monitoring and recurrence of IgG4-RD. This review summarizes the applications of 18F-FDG PET/CT in patients with IgG4-RD. Key words: Autoimmune diseases; Immunoglobulin G; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose; Trends

Imaging analysis of 18F-FDG PET/CT in patients with multiple myeloma

Objective To analyze the imaging characteristics of 18F-fluorodeoxyglucose (FDG) PET/CT in patients with multiple myeloma (MM). Methods Sixty-eight patients (41 males, 27 females, age (61.5±17.2) years) with pathologically proven MM were retrospectively reviewed between January 2011 and August 2016. Imaging characteristics of 18F-FDG PET/CT in patients were analyzed. Maximum standardized uptake value (SUVmax), score of the bone involvement (bones of whole body were classified into 10 groups, and when 1 group was involved, the score was 1), the number of bone lesions and soft tissue swelling around bone lesions were investigated. Results A total of 1 310 lesions were detected in 68 MM patients. The SUVmax varied widely and mild metabolic activity (2.5≤SUVmax<5.0) was observed in the highest proportion of MM patients (49.8%, 652/1 310). The SUVmax of MM patients was 6.63±3.02. The score of bone involvement was 4.49±3.01. The number of bone lesions was 10.50(3.00, 33.00), and soft tissue swelling around bone lesions was observed in 22 patients. Conclusions There are special imaging characteristics of 18F-FDG PET/CT in MM patients, such as multiple osteolytic lesions with mild to moderate metabolic activity, clear boundary and extensive bone involvement, and lesions usually limit to the skeletal system. The characteristics are of certain value in the diagnosis and differential diagnosis of MM. Key words: Multiple myeloma; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Clinical value of PET/CT imaging of cerebral blood flow and metabolism in patients with chronic disorders of consciousness

Objective To investigate the value of PET/CT imaging of cerebral glucose metabolism (CGM) and cerebral blood flow (CBF) in evaluating chronic disorders of consciousness (CDC). Methods A total of 10 CDC patients (5 males, 5 females, age (50.9±17.2) years) and 10 healthy controls (5 males, 5 females, age (52.0±10.3) years) from January 2016 to March 2017 were recruited to perform brain PET/CT of CGM and CBF. The brain PET imaging using 13N-Ammonia was performed and followed by 18F-fluorodeoxyglucose (FDG) PET. The mean standardized uptake values (SUVmean) of frontal, parietal, temporal and occipital lobes as well as basal ganglia, thalamus were obtained. The SUVmean of cerebral regions/SUVmean of cerebellum ratios (SUVr) were acquired. The SUVr were compared between the patients and controls. The imaging characteristics of CGM and CBF were investigated, and their relationships with clinical scores were further analyzed. Two-sample t test and Pearson correlation analysis were used to analyze the data. Results The radioactive distribution in the brain of healthy controls was symmetrical. SUVr of cerebral regions in the affected side of patients were significantly lower than those of the controls both in CGM imaging and CBF imaging (t values: 2.90-5.19, all P<0.05). In 10 CDC patients, there were 9 with hypometabolism in basal ganglia and thalamus, 8 with hypometabolism in frontal and parietal lobes, and 7 with hypometabolism in temporal and occipital lobes. At the same time, there were 7 with parietal hypoperfusion and 6 with hypoperfusion in other cerebral regions in the CDC patients. In the frontal, parietal lobes and basal ganglia, the CGM and CBF were both correlated with the clinical scores (r values: 0.473-0.606, all P<0.05). Abnormal metabolism-perfusion patterns were divided into 3 types. Type Ⅰ included 2 patients and their hypometabolism and hypoperfusion were mismatched completely. Type Ⅱ included 3 patients and their hypometabolism and hypoperfusion were matched in frontal, parietal, occipital and temporal lobes, while mismatched in basal ganglia and thalamus. Type Ⅲ included 5 patients and their hypometabolism and hypoperfusion were matched completely. The clinical scores of typeⅠ, Ⅱand Ⅲ were 10.5, 8.3 and 5.6, respectively. Conclusion The PET/CT imaging of cerebral blood flow and metabolism is useful in evaluating the disorders of consciousness. Key words: Consciousness disorders; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose; Ammonia

Co-occurring KRAS mutation/LKB1 loss in non-small cell lung cancer cells results in enhanced metabolic activity susceptible to caloric restriction: an in vitro integrated multilevel approach

BackgroundNon–small-cell lung cancer (NSCLC) is a heterogeneous disease, with multiple different oncogenic mutations. Approximately 25–30% of NSCLC patients present KRAS mutations, which confer poor prognosis and high risk of tumor recurrence. About half of NSCLCs with activating KRAS lesions also have deletions or inactivating mutations in the serine/threonine kinase 11 (LKB1) gene. Loss of LKB1 on a KRAS-mutant background may represent a significant source of heterogeneity contributing to poor response to therapy.MethodsHere, we employed an integrated multilevel proteomics, metabolomics and functional in-vitro approach in NSCLC H1299 isogenic cells to define their metabolic state associated with the presence of different genetic background. Protein levels were obtained by label free and single reaction monitoring (SRM)-based proteomics. The metabolic state was studied coupling targeted and untargeted mass spectrometry (MS) strategy. In vitro metabolic dependencies were evaluated using 2-deoxy glucose (2-DG) treatment or glucose/glutamine nutrient limitation.ResultsHere we demonstrate that co-occurring KRAS mutation/LKB1 loss in NSCLC cells allowed efficient exploitation of glycolysis and oxidative phosphorylation, when compared to cells with each single oncologic genotype. The enhanced metabolic activity rendered the viability of cells with both genetic lesions susceptible towards nutrient limitation.ConclusionsCo-occurrence of KRAS mutation and LKB1 loss in NSCLC cells induced an enhanced metabolic activity mirrored by a growth rate vulnerability under limited nutrient conditions relative to cells with the single oncogenetic lesions. Our results hint at the possibility that energy stress induced by calorie restriction regimens may sensitize NSCLCs with these co-occurring lesions to cytotoxic chemotherapy.

Random mutagenesis of super Koji (Aspergillus oryzae): improvement in production and thermal stability of \u03b1-amylases for maltose syrup production

BackgroundAlpha-amylases hydrolyze 1,4 α-glycosidic bonds of starch and produce malto-oligosaccharides. It is an important enzyme generally applied in textile, food and brewing industries. Enhancement in thermal stability and productivity of enzymes are the two most sought after properties for industrial use. The Aspergillus oryzae (Koji) has Generally Recognized as Safe (GRAS) status and safe for use in food industry. Hence, Koji strain’s development for the screening of potent mutants, hyper producer of thermostable α-amylases, with desired attributes is the need of the time.ResultsA process has been developed to improve super Koji (A. oryzae cmc1) strain through γ-rays treatment. The doses i.e. 0.60, 0.80, 1.00, 1.20 & 1.40 KGy gave more than 3.0 log kill. Initially, 52 Koji mutants resistant to 1% (w/v) Triton X-100 were selected. 2nd screening was based on α-amylases hyper production and 23 mutants were sorted out by measuring clearing zones index (CI). Afterwards nine potent mutants, resistant to 2-deoxy D-glucose, were screened based on CI. These were further analyzed for thermal stability and productivity of α-amylase under submerged conditions. The mutants’ M-80(10), M-100(6) & M-120(5) gave about four fold increases in α-amylases productivity. The half life of M-100(6) α-amylase at 55 °C was 52 min and was highest among the mutants. Liquid Chromatography-Mass Spectrometry (LC-MS) analysis confirmed that mutants did not produce aflatoxins. Field Emission Scanning Electron Microscopy (FESEM) of Koji mycelia depicted that exposure to gamma rays increased rigidity of the mycelium. The potent Koji mutant M-100(6) was grown on soluble starch in 10L fermenter and produced 40.0 IU ml-1 of α-amylases with specific activity of 2461 IU mg-1 protein. Growth kinetic parameters were: μ = Specific growth rate= 0.069 h-1, td = Biomass doubling time= 10.0 h, Yp/x = Product yield coefficient with respect to cell mass = 482 U g-1; qp= Specific rate of product formation= 33.29 U g-1 h-1.ConclusionIt was concluded that the developed five step screening process has great potential to generate potent mutants for the hyper production of thermostable enzymes through γ-rays mediated physical mutagenesis. The developed thermostable α-amylases of super Koji mutantM-100(6) has immense potential for application in saccharification process for maltose syrup production. Moreover, the developed five step strain’s development process may be used for the simultaneous improvement in productivity and thermal stability of other microbial enzymes.

Application of 18F-FDG microPET/CT in the screening of cerebral ischemia reperfusion models

Objective To investigate the feasibility of 18F-fluorodeoxyglucose (FDG) microPET/CT in the screening of cerebral ischemia reperfusion (CIR) models. Methods The suture-occluded method was used to establish CIR rat models with reversible middle cerebral artery embolism. After that only awake rats whose Zea-Longa scores were 1-4 were selected for the following experiments, and 18 male SD rats were selected. Garcia scale with 18 points was used to evaluate the neurological function of rats at 2 and 24 h post-operation. At the same time points, 18F-FDG was injected into caudal vein after anesthesia and microPET/CT scan was conducted at 40 min post-injection. Visual and semi-quantitative analyses were adopted to analyze the images. The autopsy and HE staining were performed on accidentally dead rats. The other alive rats were sacrificed after microPET/CT scan at 24 h post-operation, and their brain tissues were taken out quickly to detect the infarction by triphenyl tetrazolium chloride (TTC) staining. The pathological results were taken as the gold criteria. Fisher exact test was used to compare the difference of accuracy for diagnosing CIR models between neurological function score (NFS) and microPET/CT. Results According to the pathology, there were 11 CIR models, 4 with subarachnoid hemorrhage (SAH), 3 with SAH and cerebral hemorrhage. Between 8-12 h post-operation, 4 rats died accidentally. At 2 h post-operation, the diagnostic accuracies of NFS and microPET/CT were 11/18 and 15/18 (P 0.05). Conclusion 18F-FDG microPET/CT is better than NFS in screening CIR models in early stage. Key words: Brain ischemia; Reperfusion; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose; Rats

Characteristics of cerebral glucose metabolism in patients with corticobasal degeneration

Objective To identify abnormal cerebral glucose metabolism characteristics in patients with corticobasal degeneration (CBD) using 18F-fluorodeoxyglucose (FDG) PET imaging. Methods From January 2014 to January 2017, resting-state brain 18F-FDG PET imaging was performed in 10 CBD patients (5 males, 5 females; average age: (63.4±6.2) years) and 20 age-matched healthy subjects (8 males, 12 female; average age: (63.6±6.2) years). Voxel-based statistical parametric mapping (SPM) was used to analyze images to obtain the CBD-related brain metabolic characteristics. The regional cerebral metabolic rate of glucose (rCMRglc) was compared between 2 groups by two-sample t test. Results Compared with healthy controls, CBD group demonstrated asymmetrically decreased glucose metabolism mainly in the cerebral hemisphere opposite to the more clinically affected body side, including the superior, middle and inferior frontal gyrus, the precentral gyrus, the superior and inferior parietal lobule, the angular gyrus, the supramarginal gyrus, the precuneus, the middle occipital gyrus, the middle and inferior temporal gyrus, Heschl gyrus, the fusiform gyrus, the insula and the thalamus. And relatively increased glucose metabolism was present in ipsilateral precentral and postcentral gyrus, hippocampus, insula and putamen, bilateral cerebellum, paracentral lobules and pontine. The rCMRglc in those regions was significantly different between CBD patients and healthy controls (t values: 4.236-9.044, all P<0.01). Conclusion The asymmetric cerebral glucose metabolism features in CBD based on 18F-FDG PET imaging contribute to the differential diagnosis between CBD patients and healthy subjects. Key words: Cerebral cortex; Basal ganglia diseases; Nerve degeneration; Positron-emission tomography; Deoxyglucose

Selection of the field of views and its value in 18F-FDG PET/CT tumor imaging

The imaging field of view (FOV) used for most oncological 18F-fluorodeoxyglucose (FDG) PET/CT studies, from skull to mid-thigh, is typically a limited whole-body (LWB). This methodology has been suggested by the Society of Nuclear Medicine and Molecular Imaging and European Association of Nuclear Medicine guidelines. Using routine FOV for LWB may underestimate the true tumor extent because malignancy beyond the FOV might be missed. This review summarizes the optimum scan FOV for different types of tumors. For some tumors (such as lung cancer) that commonly spread to the brain, brain and (or) head should be included in the FOV. For lymphoma, especially pediatric lymphoma, which commonly involves lower extremities, true whole-body (TWB) scan should be used for cancer staging and follow up. LWB scan is optimal for melanoma which confined in the field of LWB. Key words: Neoplasms; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Glucose metabolism mediates disease tolerance in cerebral malaria

Sickness behaviors are a conserved set of stereotypic responses to inflammatory diseases. We recently demonstrated that interfering with inflammation-induced anorexia led to metabolic changes that had profound effects on survival of acute inflammatory conditions. We found that different inflammatory states needed to be coordinated with corresponding metabolic programs to actuate tissue-protective mechanisms. Survival of viral inflammation required intact glucose utilization pathways, whereas survival of bacterial inflammation required alternative fuel substrates and ketogenic programs. We thus hypothesized that organismal metabolism would be important in other classes of infectious inflammation and sought to understand its role in the prototypic parasitic disease malaria. Utilizing the cerebral malaria model, Plasmodium berghei ANKA (PbA) infection in C57BL/6J male mice, we unexpectedly found that inhibition of glycolysis using 2-deoxy glucose (2DG) conferred protection from cerebral malaria. Unlike vehicle-treated animals, 2DG-treated animals did not develop cerebral malaria and survived until ultimately succumbing to fatal anemia. We did not find any differences in parasitemia or pathogen load in affected tissues. There were no differences in the kinetics of anemia. We also did not detect differences in immune infiltration in the brain or in blood-brain barrier permeability. Rather, on pathological analyses performed on the entire brain, we found that 2DG prevented the formation of thrombi and thrombotic complications. Using thromboelastography (TEG), we found that 2DG-treated animals formed clots that were significantly less strong and stable. Together, these data suggest that glucose metabolism is involved in inflammation-induced hemostasis and provide a potential therapeutic target in treatment of cerebral malaria.

Value of 18F-FDG PET/CT in the staging, interim therapeutic and prognostic evaluation of mucosa-associated lymphoid tissue lymphoma

Objective To assess the value of 18F-fluorodeoxyglucose (FDG) PET/CT in the staging, interim therapeutic and prognostic evaluation of mucosa-associated lymphoid tissue (MALT) lymphoma. Methods Thirty-six MALT lymphoma patients (20 males, 16 females; average age: 61.7 years) confirmed by pathology from January 2008 to January 2018 were retrospectively analyzed.18F-FDG PET/CT were performed before chemotherapy and radiotherapy for staging. The detective sensitivity was evaluated. The staging results of gastric MALT lymphoma and extragastric MALT lymphoma by PET/CT were compared with Fisher exact probability method. PET/CT was performed in 17 of 36 patients after 4 courses of chemotherapy, and 17 patients were divided into positive group (≥4) and negative group (<4) according to scores of Deauville 5-point scale. The progression-free survival (PFS) was evaluated using Kaplan-Meier survival analysis. Results FDG-positive lesions were found in 31 of 36 patients with the sensitivity of 86.1%(31/36). The results of PET/CT were negative in stageⅠpatients. In stageⅡ-Ⅳ patients, the results of 18F-FDG PET/CT combined with bone marrow biopsy were in accordance with the results of clinical staging. The accuracy of PET/CT in staging of gastric MALT lymphoma patients was 9/17, which was significantly lower than that of extragastric MALT lymphoma patients (17/19; P=0.025). The PFS of negative group evaluated by interim PET/CT was longer than that of positive group (χ2=4.16, P<0.05). The 2-year PFS rates of the 2 groups were (85.7±13.2)% and (27.8 ±21.3)%, respectively. The PFS of patients with low expression of Ki-67 was significantly longer than that of patients with high Ki-67 expression(χ2=4.22, P<0.05). Conclusions In stageⅡ-Ⅳ MALT patients, 18F-FDG PET/CT combined with bone marrow biopsy can improve the staging accuracy. The staging accuracy of PET/CT in extragastric MALT lymphoma is significantly higher than that of gastric MALT lymphoma. PET/CT and Ki-67 can provide effective information on the prognostic evaluation for patients with MALT lymphoma. Key words: Lymphoma, B-cell, marginal zone; Neoplasm staging; Prognosis; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Correlation of Glut-1, Glut-3 and HK-II expression with 18F-FDG uptake in non-small cell lung cancer and pulmonary inflammatory lesions

Objective To analyze the expression of glucose transport protein (Glut)-1, Glut-3 and hexokinase (HK)-Ⅱ in non-small-cell lung cancer (NSCLC) lesions and pulmonary inflammatory lesions and discuss the correlation of them with 18F-fluorodeoxyglucose (FDG) uptake. Methods Twenty-four patients with NSCLC and 22 patients with pulmonary inflammatory lesions (25 males, 21 females; age range: 37-81 years) who underwent PET/CT from November 2012 to May 2016 were retrospectively analyzed. All patients had surgery and were confirmed by pathology. The expression of Glut-1, Glut-3 and HK-Ⅱ in the lesions was detected by immunohistochemistry. Immunohistochemical staining scores and maximum standardized uptake value (SUVmax) were calculated. One-way analysis of variance, the least significant difference t test, two-sample t test and Spearman correlation analysis were used. Results The SUVmax of NSCLC lesions was 8.71±7.62, higher than that of pulmonary inflammatory lesions (3.29±2.16; t=3.220, P 0.05), but the expression of Glut-3 was higher than that of Glut-1 and HK-Ⅱ (F=4.123, t values: 0.970, 0.150, all P<0.05) in pulmonary inflammatory lesions. Conclusions The expression of Glut-1, Glut-3 and HK-Ⅱ is higher in NSCLC lesions than that in pulmonary inflammatory lesions. Glut-1 and HK-Ⅱ are the important factors for 18F-FDG uptake in NSCLC. Glut-3 may play an important role in 18F-FDG uptake in pulmonary inflammatory lesions. Key words: Carcinoma, non-small-cell lung; Glucose transport proteins, facilitative; Hexokinase; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Prognostic value of pretreatment 18F-FDG PET/CT SUVmax on stage I-II extranodal nasal type natural killer/T-cell lymphoma

Objective To investigate the prognostic value of pretreatment 18F-fluorodeoxyglucose (FDG) PET/CT imaging on extranodal nasal type natural killer/T-cell lymphoma (ENKTL). Methods Thirty-five patients (20 males, 15 females, average age 45 years) diagnosed as Ann Arbor stage Ⅰ-ⅡENKTL from February 2013 to February 2016 were retrospectively analyzed. All patients were pathologically confirmed and underwent 18F-FDG PET/CT before treatment. The maximum standardized uptake value (SUVmax), international prognostic index score (IPI), serum lactate dehydrogenase (LDH), and immunohistochemical results were recorded. Patients were followed up for 2 years. The relationships between SUVmax, progression-free survival (PFS), pathological features and IPI were assessed using Fisher exact test. Results There were 18 ENKTL patients with progression, and 17 had no progression. Patients with SUVmax≥12.2 had worse prognosis than those with SUVmax<12.2 (P=0.001). There were correlations between SUVmax and Ki-67 (r=0.701, P=0.001), SUVmax and CD56 (r=0.393, P=0.032), SUVmax and IPI (r=0.787, P<0.01), respectively. It was also found that SUVmax, Ki-67, CD56 and IPI were related to PFS (all P<0.05). Conclusion SUVmax of 18F-FDG could be used as an important prognostic indicator for early ENKTL. Key words: Lymphoma, extranodal NK-T-cell; Prognosis; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Prognostic value of interim and end-of-treatment 18F-FDG PET/CT in patients with diffuse large B-cell lymphoma

Objective To compare the value of interim and end-of-treatment 18F-fluorodeoxyglucose (FDG) PET/CT for the prognosis of patients with diffuse large B-cell lymphoma (DLBCL). Methods A total of 116 DLBCL patients (male∶female=1∶1.32, average age: (57.87±15.89) years) whose initial treatment was rituximab+ cyclophosphamide+ doxorubicin+ vincristine+ prednisone(R-CHOP), were enrolled from 2008 to 2016. All patients underwent pre-treatment, interim and end-of-treatment 18F-FDG PET/CT. End points were progression-free survival (PFS) and overall survival (OS). Correlation between metabolic parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), Deauville score (DS), ΔSUVmax, ΔMTV, ΔTLG in the interim PET/CT and those in the end-of-treatment PET/CT was analyzed with Pearson correlation analysis. The ability of metabolic parameters to assess the prognosis was evaluated by receiver operating characteristic(ROC) curve analysis. The survival was analyzed by Kaplan-Meier method and hazard ratio (HR) was calculated by Cox regression model. Results The r values for ΔSUVmax, ΔMTV, ΔTLG of interim and end-of-treatment PET/CT were 0.630, 0.912, 0.955, respectively (all P<0.01). One hundred and four cases (89.7%, 104/116)had the same DS in the interim and end-of-treatment PET/CT, and the r value for DS between two PET/CT scans was 0.733 (P<0.01). The interim metabolic parameters were superior to that at the end of treatment in evaluating the progression. The 5-year PFS(83.1% vs 35.9%, P<0.01; HR=5.969, P<0.01) and OS (95.7% vs 75.5%, P<0.01; HR=8.161, P<0.05) rates were significantly higher in DS 1-3 group than those in DS 4-5 group. Conclusions Interim PET/CT is effective for the prediction of prognosis in DLBCL patients with R-CHOP treatment. Patients with complete remission in the interim can omit the end-of-treatment PET/CT. Key words: Lymphoma, large B cell, diffuse; Prognosis; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Prognostic value of 18F-FDG PET/CT and C-MYC gene rearrangement on chemotherapy in patients with diffuse large B-cell lymphoma

Objective To evaluate the prognostic value of the maximum standardized uptake value decrease proportion (ΔSUVmax%) on 18F-fluorodeoxyglucose (FDG) PET/CT imaging and C-MYC gene in diffuse large B cell lymphoma (DLBCL), and to find the optimal time of PET/CT imaging. Methods From September 2010 to February 2016, 171 patients (87 males, 84 females, average age: (50.66±2.56) years) with pathologically confirmed DLBCL were analyzed. 18F-FDG PET/CT were performed before and after different courses of chemotherapy (60 patients in early phase which means 1 and 2 courses; 55 patients in medium phase, 3 and 4 courses; 56 patients in late phase, 5 and 6 courses). The region of interest (ROI) was drawn and the ΔSUVmax% was calculated. Patients were evaluated with Deauville 5-point scale. Fluorescence in situ hybridization (FISH) was employed to detect C-MYC gene. Patients were followed up for 6-71 months, and progression-free survival (PFS) was calculated. χ2 test, one-way analysis of variance, Kaplan-Meier analysis and Spearman correlation analysis were used to analyze the data. Results There were 42 C-MYC gene rearrangement of 171 DLBCL patients. Age, Ann Arbor stage, international prognostic index (IPI) score, serum lactate dehydrogenase (LDH) level and therapeutic response were different between patients with C-MYC gene rearrangement and those without rearrangement (χ2: 6.139-98.339, all P 0.05). Conclusion ΔSUVmax% in the different phases of chemotherapy and C-MYC gene rearrangement have better values for predicting the prognosis of DLBCL, and 18F-FDG PET/CT imaging should be performed between 1 course and 4 courses of chemotherapy. Key words: Lymphoma, large B cell, diffuse; Prognosis; Gene rearrangement; Genes, myc; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Imaging the Effects of β-Hydroxybutyrate on Peri-Infarct Neurovascular Function and Metabolism.

Background and Purpose- Recent evidence suggests great potential of metabolically targeted interventions for treating neurological disorders. We investigated the use of the endogenous ketone body β-hydroxybutyrate (BHB) as an alternate metabolic substrate for the brain in the acute phase of ischemia because postischemic hyperglycemia and brain glucose metabolism elevation compromise functional recovery. Methods- We delivered BHB (or vehicle) 1 hour after ischemic insult induced by cortical microinjection of endothelin-1 in sensorimotor cortex of rats. Two days after ischemic insult, the rats underwent multimodal characterization of the BHB effects. We examined glucose uptake on 2-Deoxy-d-glucose chemical exchange saturation transfer magnetic resonance imaging, cerebral hemodynamics on continuous arterial spin labeling magnetic resonance imaging, resting-state field potentials by intracerebral multielectrode arrays, Neurological Deficit Score, reactive oxygen species production, and astrogliosis and neuronal death. Results- When compared with vehicle-administered animals, BHB-treated cohort showed decreased peri-infarct neuronal glucose uptake which was associated with reduced oxidative stress, diminished astrogliosis and neuronal death. Functional examination revealed ameliorated neuronal functioning, normalized perilesional resting perfusion, and ameliorated cerebrovascular reactivity to hypercapnia, suggesting improved functioning. Cellular and functional recovery of the neurogliovascular unit in the BHB-treated animals was associated with improved performance on the withdrawal test. Conclusions- We characterize the effects of the ketone body BHB administration at cellular and system levels after focal cortical stroke. The results demonstrate that BHB curbs the peri-infarct glucose-metabolism driven production of reactive oxygen species and astrogliosis, culminating in improved neurogliovascular and functional recovery.

Clinical value of 18F-FDG PET/CT in assessing muscular inflammation of dermatomyositis

Objective To analyze the imaging characteristics and diagnostic value of 18F-fluorodeoxyglucose (FDG) PET/CT in muscular inflammation in dermatomyositis (DM), as well as the relationship between maximum standardized uptake value (SUVmax) and activity of muscular inflammation. Methods From July 2013 to November 2016, 17 hospitalized DM patients (8 males, 9 females, age range: 35-78 years) who underwent 18F-FDG PET/CT were retrospectively reviewed, including 13 typical DM (TDM) and 4 amyopathic DM (ADM). Seventeen healthy volunteers (8 males, 9 females, age range: 35-78 years) in the same period were enrolled as the control group. The proximal limb muscles of whole body were divided into 7 areas, and the SUVmax of each was measured and recorded. Two-sample t test, one-way analysis of variance, Dunnett-t test and Spearman correlation analysis were used to analyze data. Results Five TDM cases showed diffuse increased FDG uptake in global muscles; 8 TDM cases showed increased FDG uptake in local muscles, mainly in the shoulder and hip. The FDG uptake by muscles of 4 ADM patients was similar with that of controls. The SUVmax was lower and lower in the order of shoulder and back muscles, hip muscles, thoracic vertebra muscles, cervical vertebra muscles, biceps, proximal quadriceps and lumbar vertebra muscles in DM group. The muscle SUVmax of DM, TDM, ADM and the controls were 1.92±0.86, 2.14±0.85, 1.19±0.44 and 0.93±0.26, respectively (F=69.50, P<0.001). Muscle SUVmax of DM group was higher than that of controls, muscle SUVmax of TDM was higher than that of ADM, and muscle SUVmax of ADM was higher than that of controls (t values: 4.102-11.970, all P<0.05). Muscle SUVmax of 9 DM patients with interstitial lung disease (ILD) was lower than that of patients without ILD (1.73±0.09 vs 2.13±0.13; t=5.857, P<0.001). Muscle SUVmax of DM was positive correlated with serum levels of creatine kinase (CK) and creatine kinase isoenzyme composed by M and B subunits (CK-MB) (rs values: 0.814 and 0.751, both P<0.001). Conclusion 18F-FDG PET/CT is helpful to detect muscular inflammation of DM and it can reflect the activity and severity with SUVmax, and meanwhile evaluate the condition of ILD associated with DM. Key words: Dermatomyositis; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose

Value of 18F-FDG PET/CT in differentiation of noninvasive and malignant pancreatic cystic lesions

Objective To investigate the value of 18F-fluorodeoxyglucose (FDG) PET/CT in differentiation of noninvasive and malignant pancreatic cystic lesions (PCL). Methods A total of 125 PCL patients (66 males, 59 females, age range: 13-83 years), who had pathology or typical imaging performance with ≥12 months follow-up between August 2010 and December 2015, were enrolled in this retrospective study. The diagnostic effects of 18F-FDG PET/CT were calculated. The size, maximum standardized uptake value (SUVmax), delayed SUVmax and retention index (RI) of noninvasive and malignant PCL were analyzed. The results of pathological examination and follow-up were used as the gold standard, and Mann-Whitney u test was used to analyze the data. Receiver operating characteristic (ROC) curves of SUVmax, delayed SUVmax and RI were drawn and compared. Results A total of 132 PCL were found in 125 patients, including 71 malignant PCL and 61 noninvasive PCL. The size, SUVmax, delayed SUVmax, RI of noninvasive and malignant PLC were 2.2 (1.4, 3.8) cm vs 3.9 (3.0, 5.0) cm, 1.5 (1.2, 1.8) vs 6.4 (4.4, 9.3), 1.5 (1.2, 1.9) vs 6.4 (5.4, 11.7), -6.3%(-19.4%, 5.6%) vs 17.5%(7.6%, 29.4%), respectively. All parameters were significantly different between 2 groups (z values: from -9.267 to -4.904, all P 0.05). Conclusion 18F-FDG PET/CT has good performance in differentiation of noninvasive and malignant PCL, but the delayed scan cannot further improve the efficacy of differential diagnosis. Key words: Pancreatic neoplasms; Diagnosis, differential; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose