Underwent 18F-fluorodeoxyglucose Positron Emission Tomography Research Articles

Different effect of hypo- and hypermetabolism on cognition in dementia with Lewy bodies: are they coupled or independent?

Patients with dementia with Lewy bodies (DLB) show widespread brain metabolic changes. This study investigated whether brain hypo- and hypermetabolism in DLB have differential effects on cognition. We enrolled 55 patients with DLB (15 prodromal DLB [MCI-LB] and 40 probable DLB) and 13 healthy controls who underwent 18F-fluorodeoxyglucose positron emission tomography and detailed neuropsychological tests. Metabolic indices reflecting associated changes in regional cerebral glucose metabolism were calculated as follows: index(-) for hypometabolism [DLB-hypo] and index(+) for hypermetabolism [DLB-hyper]. The effects of DLB-hypo or DLB-hyper on cognitive function were assessed using a multivariate linear regression model. Additionally, a linear mixed model was used to investigate the association between each index and the longitudinal cognitive decline. There was no correlation between DLB-hypo and DLB-hyper in the disease group. The multivariate linear regression model showed that DLB-hypo was associated with language, visuospatial, visual memory, and frontal/executive functions; whereas DLB-hyper was responsible for attention and verbal memory. There was significant interaction between DLB-hypo and DLB-hyper for verbal and visual memory, which was substantially affected by DLB-hyper in relatively preserved DLB-hypo status. A linear mixed model showed that DLB-hypo was associated with longitudinal cognitive outcomes, regardless of cognitive status, and DLB-hyper contributed to cognitive decline only in the MCI-LB group. The present study suggests that DLB-hypo and DLB-hyper may be independent of each other and differentially affect the baseline and longitudinal cognitive function in patients with DLB.

Greater perceived stress management skills and heightened brain metabolic activity in cortical and subcortical stress processing regions in metastatic breast cancer patients

PurposeEmotional distress and adversity can contribute to negative health outcomes in women with breast cancer. Individual differences in perceived stress management skills such as cognitive reframing and relaxation for coping with adversity have been shown to predict less distress and better psychological and physiological adaptation. Prior work shows that more distressed breast cancer patients reveal less metabolic activity in brain regions such as the insula, thalamus, ventromedial and lateral prefrontal cortices. This led us to pose the hypothesis that breast cancer patients with greater stress management skills (e.g., ability to reframe stressors and use relaxation) may conversely show greater activation in these brain regions and thereby identify brain activity that may be modifiable through stress management interventions. The main objective of this study was to examine the association of perceived stress management skill efficacy with the metabolism of 9 key stress-implicated brain regions in women diagnosed with metastatic breast cancer.MethodsSixty women (mean age 59.86 ± 10.04) with a diagnosis of mBC underwent 18F-fluorodeoxyglucose positron emission tomography. Perceived stress management skill efficacy was assessed with the Measure of Current Status Scale.ResultsGreater perceived stress management skill efficacy related significantly to higher metabolic activity in the insula, thalamus, ventromedial and lateral prefrontal cortices, and basal ganglia; this network of regions overlaps with those previously shown to be under-activated with greater level of distress in this same sample of metastatic breast cancer patients.ConclusionThis is the first study to demonstrate in metastatic cancer patients that greater perceptions of stress management skill efficacy are associated with metabolic activity in key brain regions and paves the way for future studies tracking neural mechanisms sensitive to change following stress management interventions for this population.

Reduced Stress-Related Neural Network Activity Mediates the Effect of Alcohol on Cardiovascular Risk

BackgroundChronic stress associates with major adverse cardiovascular events (MACE) via increased stress-related neural network activity (SNA). Light/moderate alcohol consumption (ACl/m) has been linked to lower MACE risk, but the mechanisms are unclear. ObjectivesThe purpose of this study was to evaluate whether the association between ACl/m and MACE is mediated by decreased SNA. MethodsIndividuals enrolled in the Mass General Brigham Biobank who completed a health behavior survey were studied. A subset underwent 18F-fluorodeoxyglucose positron emission tomography, enabling assessment of SNA. Alcohol consumption was classified as none/minimal, light/moderate, or high (<1, 1-14, or >14 drinks/week, respectively). ResultsOf 53,064 participants (median age 60 years, 60% women), 23,920 had no/minimal alcohol consumption and 27,053 ACl/m. Over a median follow-up of 3.4 years, 1,914 experienced MACE. ACl/m (vs none/minimal) associated with lower MACE risk (HR: 0.786; 95% CI: 0.717-0.862; P < 0.0001) after adjusting for cardiovascular risk factors. In 713 participants with brain imaging, ACl/m (vs none/minimal) associated with decreased SNA (standardized beta −0.192; 95% CI: −0.338 to −0.046; P = 0.01). Lower SNA partially mediated the beneficial effect of ACl/m on MACE (log OR: −0.040; 95% CI: −0.097 to −0.003; P < 0.05). Further, ACl/m associated with larger decreases in MACE risk among individuals with (vs without) prior anxiety (HR: 0.60 [95% CI: 0.50-0.72] vs 0.78 [95% CI: 0.73-0.80]; P interaction = 0.003). ConclusionsACl/m associates with reduced MACE risk, in part, by lowering activity of a stress-related brain network known for its association with cardiovascular disease. Given alcohol’s potential health detriments, new interventions with similar effects on SNA are needed.

Modern approaches to the diagnosis and treatment of cardiac sarcoidosis: results of a cohort study

Aim. To analyze clinical and paraclinical data in patients with documented cardiac sarcoidosis, outlining the key points of diagnosis and selection of the optimal treatment.Material and methods. For the period from 2016 to 2021, 63 patients (50,4±14,1 years) were included in the cohort study on negotiability. Based on a standard examination, 15 patients (41±13 years old) were selected, who continued the examination to confirm the diagnosis of cardiac sarcoidosis. Contrast-enhanced cardiac magnetic resonance imaging (MRI) was performed in 10 patients, while endomyocardial biopsy in 7 patients. All patients underwent 18F-fluorodeoxyglucose positron emission tomography (PET).Results. The most common (53%) electrocardiographic abnormality was right bundle branch block. Ventricular arrhythmias and high-grade atrioventricular block were recorded mainly in patients with documented activity. Regional contractility disorders were predominantly detected in patients with cardiac fibrosis. Delayed contrast enhancement according to cardiac MRI was recorded mainly intramurally in the interventricular septum and subepicardial area of left ventricular (LV) lateral wall. When analyzing the PET results, we found the predominant radiopharmaceutical accumulation in the interventricular septum (56%), lateral (44%) and anterior (33%) LV walls. There was no significant improvement in global LV contractility against the background of immunosuppressive therapy, especially in patients with reduced ejection fraction: initially 49,2±10,1% vs 46,9±14,9% during therapy (p=0,658).Conclusion. A certain apprehensive attitude of the doctor and adherence to the algorithm for early diagnosis of cardiac sarcoidosis allows minimizing the risks of fatal cardiovascular events. On the contrary, in the case of late diagnosis, even the use of aggressive immunosuppressive therapy does not lead to an improvement in global myocardial contractility, and fibrosis zones can cause life-threatening bradyarrhythmias and ventricular arrhythmias.

Disruption in normal correlational patterns of metabolic networks in the limbic circuit during transient global amnesia.

Transient global amnesia is characterized by the sudden apparition of severe episodic amnesia, mainly anterograde, associated with emotional changes. Even though the symptoms are stereotyped, cerebral mechanism underlying transient global amnesia remains unexplained and previous studies using positron emission tomography do not show any clear results or consensus on cerebral regions impacted during transient global amnesia. This study included a group of 10 transient global amnesic patients who underwent 18F-fluorodeoxyglucose positron emission tomography during the acute or recovery phase of the episode and 10 paired healthy controls. Episodic memory was evaluated with the encoding-storage-retrieval paradigm and a story recall test of the Wechsler's memory scale and anxiety was assessed with the Spielberger scale. We used statistical parametric mapping to identify modifications of whole-brain metabolism. Regarding hypometabolism, there was no brain region systematically affected in all transient global amnesic patients and the comparison between amnesic patients and controls did not show any significant differences. To better understand the specific implication of the limbic circuit in the pathophysiology of transient global amnesia, we then conducted a correlational analysis that included regions of this network. Our findings showed that in healthy controls, regions of the limbic circuit seem to operate in a synchronized way with all regions being highly correlated to each other. On the opposite, in transient global amnesic patients, we observed a clear disruption of this normal correlational patterns between regions with the medial temporal lobe (the hippocampus, parahippocampal gyrus and amygdala) included in one cluster and the orbitofrontal cortex, anterior and posterior cingulate gyrus and thalamus gathered in the other one. Given the individual variability in the time course of transient global amnesia, the direct comparison between a group of patients and controls does not seem to favour the identification of subtle and transient alterations in regional metabolism. The involvement of an extended network, such as the limbic circuit, seems more likely to explain the symptoms of patients. Indeed, the synchronization of regions within the limbic circuit seems to be altered during transient global amnesia, which could explain the amnesia and anxiety observed in transient global amnesic patients. The present study thus deepens our understanding of the mechanisms underlying not only amnesia but also the emotional component of transient global amnesia by considering it as a disruption in the normal correlational patterns within the limbic circuit.

Correlations among KRAS Mutation, Microsatellite Instability, and 18F-FDG Uptake in Colon Cancer.

This study aimed to evaluate the correlation of the maximum standardized uptake value (SUVmax) with the Kirsten ras sarcoma viral oncogene (KRAS) mutation and microsatellite instability (MSI) status in colon cancer. This retrospective study included 195 patients with colon cancer who underwent 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET/CT) before surgery between January 2014 and December 2017. All patients underwent KRAS mutation and MSI analyses using surgical specimens of the primary tumor. The associations of SUVmax with KRAS mutation and MSI were analyzed. The SUVmax differed significantly between the microsatellite stable (MSS) and MSI groups (14.5 ± 7.0 vs. 19.1 ± 10.9; P = 0.0249), and between the KRAS wild-type and KRAS mutation groups (14.1 ± 7.6 vs. 17.5 ± 7.9; P = 0.0017). SUVmax obtained using 18F-FDG PET/CT showed significant differences in relation to KRAS mutation and MSI status. 18F-FDG PET/CT could be used as a supplemental modality for assessing KRAS mutations and MSI status in colon cancer.

Identification of the main components of spontaneous speech in primary progressive aphasia and their neural underpinnings using multimodal MRI and FDG-PET imaging

BackgroundPrimary progressive aphasia (PPA) is a clinical syndrome characterized by gradual loss of language skills. This study aimed to evaluate the diagnostic capacity of a connected speech task for the diagnosis of PPA and its variants, to determine the main components of spontaneous speech, and to examine their neural correlates. MethodsA total of 118 participants (31 patients with nfvPPA, 11 with svPPA, 45 with lvPPA, and 31 healthy controls) were evaluated with the Cookie Theft picture description task and a comprehensive language assessment protocol. Patients also underwent 18F-fluorodeoxyglucose positron emission tomography and magnetic resonance imaging studies. Principal component analysis and machine learning were used to evaluate the main components of connected speech and the accuracy of connected speech parameters for diagnosing PPA. Voxel-based analyses were conducted to evaluate the correlation between spontaneous speech components and brain metabolism, brain volumes, and white matter microstructure. ResultsDiscrimination between patients with PPA and controls was 91.67%, with 77.78% discrimination between PPA variants. Parameters related to speech rate and lexical variables were the most discriminative for classification. Three main components were identified: lexical features, fluency, and syntax. The lexical component was associated with ventrolateral frontal regions, while the fluency component was associated with the medial superior prefrontal cortex. Number of pauses was more related with the left parietotemporal region, while pauses duration with the bilateral frontal lobe. The lexical component was correlated with several tracts in the language network (left frontal aslant tract, left superior longitudinal fasciculus I, II, and III, left arcuate fasciculus, and left uncinate fasciculus), and fluency was linked to the frontal aslant tract. ConclusionSpontaneous speech assessment is a useful, brief approach for the diagnosis of PPA and its variants. Neuroimaging correlates suggested a subspecialization within the left frontal lobe, with ventrolateral regions being more associated with lexical production and the medial superior prefrontal cortex with speech rate.

Impact of Antibiotic Therapy and Metabolic Parameters in Non-Small Cell Lung Cancer Patients Receiving Checkpoint Inhibitors

Introduction: In the current study, we aimed to assess the impact of antibiotics (ATB) and metabolic parameters on clinical outcome of non-small cell lung carcinoma (NSCLC) patients treated with immune checkpoint inhibitors (ICI). Methods: Data from fifty NSCLC patients referred for ICI between December 2015 and May 2019 were analyzed. All patients underwent 18F-fluorodeoxyglucose positron emission tomography computed tomography (18F-FDG PET/CT) and contrast-enhanced CT at baseline and for response assessment after 6–8 weeks. Patients who received ATB within 1 month before or after the first dose of ICI were compared with those who did not. Response assessment according to iRECIST and EORTC was evaluated, as well as progression-free survival (PFS) and overall survival (OS). For semi-quantitative parameters, we computed metabolic tumor volume (MTV), total lesion glycolysis (TLG) and their variations (∆). Results: Twenty NSCLC cases of 50 (40%) had received ATB. Patients receiving ATB had a higher number of metastases (p = 0.046), and were associated with an elevated tumor burden, expressed by TLG (687 vs. 235.3, p = 0.007) and MTV (125.6 vs. 40.6, p = 0.002), compared to no-ATB patients. According to iRECIST, progressive disease rate was significantly higher for ATB group (64.7% vs. 27.6%, p = 0.029). Likewise, PFS was shorter for ATB compared to no-ATB (median 4.1 vs. 12.4 months, p = 0.004), while no difference for OS was detected. On multivariate analysis, the effect of ATB remained significant for poor PFS along with performance status (ECOG ≥ 1), and ∆SUVmax. Conclusions: ATB therapy seems to be associated with a worse treatment response, PFS, and higher metabolic tumor burden in NSCLC patients treated with ICI.

A Feedforward Loop within the Thyroid-Brown Fat Axis Facilitates Thermoregulation

Thyroid hormones (TH) control brown adipose tissue (BAT) activation and differentiation, but their subsequent homeostatic response following BAT activation remains obscure. This study aimed to investigate the relationship between cold- and capsinoids-induced BAT activation and TH changes between baseline and 2 hours post-intervention. Nineteen healthy subjects underwent 18F-fluorodeoxyglucose positron-emission tomography (18F-FDG PET) and whole-body calorimetry (WBC) after 2 hours of cold exposure (~14.5 °C) or capsinoids ingestion (12 mg) in a crossover design. Standardized uptake values (SUV-mean) of the region of interest and energy expenditure (EE) were measured. Plasma free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) were measured before and 2 hours after each intervention. Subjects were divided into groups based on the presence (n = 12) or absence (n = 7) of BAT after cold exposure. 12 of 19 subjects were classified as BAT-positive. Subjects with BAT had higher baseline FT3 concentration, baseline FT3/FT4 ratio compared with subjects without BAT. Controlling for body fat percentage, FT3 concentration at baseline was associated with EE change from baseline after cold exposure (P = 0.037) and capsinoids (P = 0.047). Plasma FT4 level significantly increased associated with reciprocal decline in TSH after acute cold exposure and capsinoids independently of subject and treatment status. Circulating FT3 was higher in BAT-positive subjects and was a stronger predictor of EE changes after cold exposure and capsinoids in healthy humans. BAT activation elevates plasma FT4 acutely and may contribute towards augmentation of thermogenesis via a positive feedback response.

Epileptogenic zone localization using a new automatic quantitative analysis based on normal brain glucose metabolism database

Objectives To assess the clinical value of voxel-based automatic quantitative analysis using a normal brain glucose metabolism database in the preoperative localization of focal intractable temporal lobe epilepsy patients. Methods Patients with refractory temporal lobe epilepsy who underwent 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) imaging were retrospectively enrolled from January to June 2017. Visual analysis was performed by two nuclear medicine radiologists, and the automatic quantitative analysis was carried out using MIMneuro software based the age- and gender-stratified normal brain glucose metabolism database. Setting postoperative outcomes as reference, the consistency between visual analysis and automatic quantitative analysis was tested by Cohen’s kappa coefficient, and differences in localization of epileptic foci of the two methods were compared by Chi-square test. Results A total of 32 patients intractable temporal lobe epilepsy were included in this study. There was a moderate agreement between the automatic quantitative analysis based on MIMneuro software and visual analysis (kappa coefficient = 0.472, p = 0.002). In terms of the efficiency of focus localization, the voxel-based automatic quantitative analysis was higher than that of visual analysis (Chi-square value = 6.969, p = 0.008). Conclusions The voxel-based automatic quantitative analysis combined with normal brain glucose metabolism database had a certain clinical application value for detection temporal lobe epilepsy.

Association of metabolic and genetic heterogeneity in head and neck squamous cell carcinoma with prognostic implications: integration of FDG PET and genomic analysis

PurposeThe linkage between the genetic and phenotypic heterogeneity of the tumor has not been thoroughly evaluated. Herein, we investigated how the genetic and metabolic heterogeneity features of the tumor are associated with each other in head and neck squamous cell carcinoma (HNSC). We further assessed the prognostic significance of those features.MethodsThe mutant-allele tumor heterogeneity (MATH) score (n = 508), a genetic heterogeneity feature, and tumor glycolysis feature (GlycoS) (n = 503) were obtained from the HNSC dataset in the cancer genome atlas (TCGA). We identified matching patients (n = 33) who underwent 18F-fluorodeoxyglucose positron emission tomography (FDG PET) from the cancer imaging archive (TCIA) and obtained the following information from the primary tumor: metabolic, metabolic-volumetric, and metabolic heterogeneity features. The association between the genetic and metabolic features and their prognostic values were assessed.ResultsTumor metabolic heterogeneity and metabolic-volumetric features showed a mild degree of association with MATH (n = 25, ρ = 0.4~0.5, P < 0.05 for all features). The patients with higher FDG PET features and MATH died sooner. Combination of MATH and tumor metabolic heterogeneity features showed a better stratification of prognosis than MATH. Also, higher MATH and GlycoS were associated with significantly worse overall survival (n = 499, P = 0.002 and 0.0001 for MATH and GlycoS, respectively). Furthermore, both MATH and GlycoS independently predicted overall survival after adjusting for clinicopathologic features and the other (P = 0.015 and 0.006, respectively).ConclusionBoth tumor metabolic heterogeneity and metabolic-volumetric features assessed by FDG PET showed a mild degree of association with genetic heterogeneity in HNSC. Both metabolic and genetic heterogeneity features were predictive of survival and there was an additive prognostic value when the metabolic and genetic heterogeneity features were combined. Also, MATH and GlycoS were independent prognostic factors in HNSC; they can be used for precise prognostication once validated.

Surveillance Imaging after Autologous Hematopoietic Cell Transplantation Predicts Survival in Patients with Diffuse Large B Cell Lymphoma.

The utility of surveillance imaging after autologous hematopoietic cell transplantation (AHCT) in relapsed/refractory diffuse large B cell lymphoma (DLBCL) remains unclear. The purpose of this study was to determine whether surveillance imaging predicts survival after AHCT. At the University of Minnesota, serial imaging for early relapse detection has been used prospectively for all consecutive AHCT recipients treated since 2010. The present analysis included 91 AHCT recipients with DLBCL who underwent 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) scan at day +100 post-AHCT. 18F-FDG-PET parameters included the Deauville (D) 5-point scale, peak standardized uptake values (SUVmax), total legion glycolysis (TLG), and total metabolic tumor volume (TMTV). Survival of patients with clinically symptomatic versus asymptomatic radiographically detected relapsed DLBCL after AHCT was compared. Sixty patients experienced relapse; 35% was detected on day +100 surveillance PET scan. 5-year overall survival (OS) by 18F-FDG-PET scan at day +100 post-AHCT was significantly lower in D4 and D5 patients (37%; 95% confidence interval [CI], 14% to 100% versus 25%; 95% CI, 43% to 89%) compared with patients with D1 and D2 (62%; 95% CI, 43% to 89% versus 62%; 95% CI, 46% to 84%). TLG and TMTV were not prognostic. SUVmax at day +100 varied from 1.5 (D1) to 17.9 (D5). In multivariate analysis, only SUVmax was predictive of relapse and OS; mortality increased 1.8-fold with each SUVmax doubling (hazard ratio [HR], 1.8; 95% CI, 1.3 to 2.3; P < .01). At a median follow-up of 3.3 years (range, 1 to 12 years), lymphoma-related mortality was 1.8-fold higher among patients whose relapse was detected clinically (symptomatic) versus radiographically on surveillance scan (HR, 1.8; 95% CI, .9 to 3.4; P=.08). In patients with relapsed/refractory DLBCL, a routine PET imaging at day +100 post-AHCT detects asymptomatic relapse and high SUVmax identifies patients with poor expected survival of less than 1 year. Identifying this high-risk cohort can potentially highlight patients who might benefit from preemptive interventions to prevent or delay relapse.

Correlation between 18F-FDG maximum standardized uptake value with CD147 expression in lung adenocarcinomas: a retrospective study

BackgroundThe pro-tumoral action of the cluster of differentiation 147 (CD147), which is associated with the chemotherapy resistance of lung adenocarcinoma, is partly due to accelerated tumor cell glycolysis. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) metabolic parameters included maximal standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), which are non-invasive markers of the glucose metabolism of tumor cells in vivo. This study aimed to clarify the correlation between PET metabolic parameters and CD147 expression, and to evaluate the prognostic value of CD147 expression in resectable lung adenocarcinoma patients.MethodsA total of 89 lung adenocarcinoma chemotherapy-naive patients who underwent 18F-fluorodeoxyglucose positron emission tomography and computerized tomography scan before pulmonary surgery were retrospectively analyzed. The PET metabolic parameters were calculated by 18F-FDG PET imaging, and CD147 expression was analyzed by immunohistochemistry. SUVmax, SUVmean, MTV, and TLG compared for their performance in predicting the expression of CD147 were illustrated with statistical analysis. All patients were then followed-up for survival analysis.ResultsThe SUVmax was significantly correlated with the CD147 expression and was the primary predictor for the CD147 expression of lung adenocarcinoma. A cut-off value of the SUVmax, 9.77 allowed 85.1% sensitivity and 64.3% specificity for predicting the CD147 positive lung adenocarcinoma. CD147 expression was correlated with tumor differentiation and metastasis. Univariate survival analysis showed that CD147 expression was significantly associated with a shorter overall survival (OS) time. Multivariate analysis revealed that CD147 was an independent prognostic factor of lung adenocarcinoma patients.ConclusionThe SUVmax of a primary tumor measured with 18F-FDG PET may be a simple and non-invasive marker for predicting CD147 expression in lung adenocarcinoma. CD147 is an independent prognostic factor related to OS of postoperative lung adenocarcinoma patients.

Prospective evaluation of metabolic intratumoral heterogeneity using 18F-FDG-PET-CT in patients with advanced gastric cancer receiving palliative chemotherapy.

4059 Background: Metabolic intratumoral heterogeneity (ITH) gives important information on treatment response and prognosis. However, temporal changes in metabolic ITH and their associations with treatment outcome have not been reported yet in gastric cancer (GC). We aimed to evaluate the early changes in metabolic ITH and their predictive roles in advanced GC patients receiving palliative chemotherapy. Methods: Unresectable locally advanced or metastatic GC patients were prospectively enrolled before the first-line palliative chemotherapy and underwent 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET-CT) at baseline (T1) and at the first response evaluation follow-up (T2). SUVs (Standardized uptake values), volumetric parameters, and textural features including entropyHisto and contrastGLCM were extracted from the primary gastric tumor at T1, T2, and ΔT (T2-T1) was evaluated. Associations of these parameters with treatment response, progression-free survival (PFS), and overall survival (OS) were analyzed. Results: 87 patients were analyzed. Of 86 evaluable patients, 44 obtained partial response, 33 stable disease, and 8 progressed. The objective response rate was 51.8% (95% confidence interval [CI], 40.7% to 62.7%). The median PFS and OS were 7.3 months (95% CI, 5.4 to 8.2 months) and 11.5 months (95% CI, 10.1 to 14.3 months), respectively. From T1 to T2, metabolic ITH was significantly reduced ( P &lt; 0.01), and the degree of decrease was greater in responders than in non-responders ( P &lt; 0.01). By multiple Cox regression analyses adjusted for clinical variables, low entropyHisto at T2 ( P= 0.001), larger decreases in coefficient of variance ( P= 0.003) and contrastGLCM ( P= 0.017) were associated with better PFS. Low SUVpeak at T2 ( P= 0.001), larger decreases in coefficient of variance ( P= 0.032) and being a responder were associated with better OS. Conclusions: Early reduction in metabolic ITH is useful to predict response to palliative chemotherapy, PFS and OS in advanced GC patients.

Clinical experience of positron-emission tomography in infective aortic disease.

Background Fluorine-18-fluorodeoxyglucose positron-emission tomography with computed tomography has revolutionized medical diagnosis by adding functional activity to anatomic imaging. We report our experience with this technique in patients with mycotic aortic pathology and aortic vascular graft infection. Methods We conducted a retrospective review of a prospective database of patients who underwent 18F-fluorodeoxyglucose positron-emission tomography with computed tomography for suspected infective aortic disease. From 2012 to 2016, 13 patients underwent 18F-fluorodeoxyglucose positron-emission tomography. Of these, 9 (69%) had a vascular graft infection (5 infrarenal aorta, 1 para-visceral, 2 descending, and 1 arch; 2 had previous open surgery and 7 had endovascular interventions) and 4 (31%) had a mycotic aneurysm (2 aortic arch, 1 infrarenal aorta, and 1 distal aorta and common iliac; 3 had endografts). The indications for imaging, location of pathology, 18F uptake, and clinical outcomes were analyzed. Results Eight (62%) patients had a single scan and 5 (38%) had serial scans performed. Among the 5 patients who had serial imaging, 3 showed decreased 18F uptake and 2 had increased uptake. Only one patient underwent subsequent endograft removal; the others were treated with lifelong antibiotics. There were 5 (38%) deaths on follow-up. Conclusion 18F-fluorodeoxyglucose positron-emission tomography with computed tomography could be a valuable adjunct in the diagnosis and surveillance of patients with aortic infection. Serial scans may be useful for monitoring disease activity and response to antibiotic therapy.

Decreased Metabolism in the Posterior Medial Network with Concomitantly Increased Metabolism in the Anterior Temporal Network During Transient Global Amnesia.

Perturbation of corticohippocampal circuits is a key step in the pathogenesis of transient global amnesia. We evaluated the spatial distribution of altered cerebral metabolism to determine the location of the corticohippocampal circuits perturbed during the acute stage of transient global amnesia. A consecutive series of 12 patients with transient global amnesia who underwent 18F-fluorodeoxyglucose positron emission tomography within 3 days after symptom onset was identified. We used statistical parametric mapping with two contrasts to identify regions of decreased and increased brain metabolism in transient global amnesia patients compared with 25 age-matched controls. Transient global amnesia patients showed hypometabolic clusters in the left temporal and bilateral parieto-occipital regions that belong to the posterior medial network as well as, hypermetabolic clusters in the bilateral inferior frontal regions that belong to the anterior temporal network. The posterior medial and anterior temporal networks are the two main corticohippocampal circuits involved in memory-guided behavior. Decreased metabolism in the posterior medial network might explain the impairment of episodic memory observed during the acute stage of transient global amnesia. Concomitant increased metabolism within the anterior temporal network might occur as a compensatory mechanism.

Risk-adapted robotic stereotactic body radiation therapy for inoperable early-stage non-small-cell lung cancer.

To evaluate efficacy and toxicity of stereotactic body radiation therapy (SBRT) with CyberKnife® (Accuray, Sunnyvale, CA, USA) in aselected cohort of primary, medically inoperable early-stage non-small cell lung cancer (NSCLC) patients. From 2012 to 2016, 106patients (median age 74years, range 50-94years) with primary NSCLC were treated with SBRT using CyberKnife®. Histologic confirmation was available in 87patients (82%). For mediastinal staging, 92patients (87%) underwent 18F-fluorodeoxyglucose positron-emission tomography (18-FDG-PET) and/or endobronchial ultrasound (EBUS)-guided lymph node biopsy or mediastinoscopy. Tumor stage (UICC8, 2017) was IA/B (T1a-c, 1-3 cm) in 86patients (81%) and IIA (T2a/b, 3-5 cm) in 20 patients (19%). Depending on tumor localization, three different fractionation schedules were used: 3fractions of 17Gy, 5fractions of 11Gy, or 8fractions of 7.5 Gy. Tracking was based on fiducial implants in 13patients (12%) and on image guidance without markers in 88%. Median follow-up was 15months (range 0.5-46 months). Acute side effects were mild (fatigue grade1-2 in 20% and dyspnea grade1-2 in 17%). Late effects were observed in 4patients (4%): 3patients developed pneumonitis requiring therapy (grade2) and 1patient suffered arib fracture (grade3). In total, 9/106patients (8%) experienced alocal recurrence, actuarial local control rates were 88% (95% confidence interval, CI, 80-96%) at 2years and 77% (95%CI 56-98%) at 3years. The median disease-free survival time was 27months (95%CI 23-31months). Overall survival was 77% (95%CI 65-85%) at 2years and 56% (95%CI 39-73%) at 3years. CyberKnife® lung SBRT which allows for real-time tumor tracking and risk-adapted fractionation achieves satisfactory local control and low toxicity rates in inoperable early-stage primary lung cancer patients.

Moderate Physical Activity is Associated with Cerebral Glucose Metabolism in Adults at Risk for Alzheimer's Disease.

The objective of this study was to investigate the relationship between accelerometer-measured physical activity (PA) and glucose metabolism in asymptomatic late-middle-aged adults. Ninety-three cognitively healthy late-middle-aged adults from the Wisconsin Registry for Alzheimer's Prevention participated in this cross-sectional study. They underwent 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging and wore an accelerometer (ActiGraph GT3X+) to measure free-living PA. Accelerometer data yielded measures of light (LPA), moderate (MPA), and vigorous (VPA) intensity PA. FDG-PET images were scaled to the cerebellum and pons, and cerebral glucose metabolic rate was extracted from specific regions of interest (ROIs) known to be hypometabolic in AD, i.e., hippocampus, posterior cingulate, inferior temporal cortex, and angular gyrus. Regression analyses were utilized to examine the association between PA and glucose metabolism, while adjusting for potential confounds. There were associations between MPA and glucose metabolism in all ROIs examined. In contrast, LPA was not associated with glucose uptake in any ROI and VPA was only associated with hippocampal FDG uptake. Secondary analyses did not reveal associations between sedentary time and glucose metabolism in any of the ROIs. Exploratory voxel-wise analysis identified additional regions where MPA was significantly associated with glucose metabolism including the precuneus, supramarginal gyrus, amygdala, and middle frontal gyrus. These findings suggest that the intensity of PA is an important contributor to neuronal function in a late-middle-aged cohort, with MPA being the most salient. Prospective studies are necessary for fully elucidating the link between midlife engagement in PA and later life development of AD.

First-line chemotherapy with pemetrexed plus cisplatin for malignant peritoneal mesothelioma

ABSTRACTBackground: Mesothelioma of peritoneal origin has wider variation in treatment outcomes than mesothelioma of pleural origin, likely because peritoneal mesothelioma comprises borderline malignant variants and aggressive malignant peritoneal mesothelioma (MPeM). This study retrospectively evaluates the efficacy of first-line systemic pemetrexed and cisplatin chemotherapy in MPeM.Research design and methods: Twenty-four patients with histologically proven MPeM were treated with pemetrexed plus cisplatin as a first-line systemic chemotherapy. The response was evaluated radiologically according to standard Response Evaluation Criteria In Solid Tumors (RECIST) criteria. Twenty-two patients underwent 18F-fluorodeoxyglucose positron emission tomography/(FDG-PET)/computed tomography(CT) at baseline, and 13 were eligible for metabolic assessment.Results: Two complete responses and 9 partial responses were achieved. Overall response rate and disease control rate were 45.8% and 91.7%, respectively. Median progression-free survival and median overall survival were 11.0 months and 15.8 months, respectively. Wet- type MPeM had significantly longer survival (40.9 months median) than other clinical types (15.5 months) (P = 0.045). The baseline maximum standardized uptake value in 22 patients was 8.93 (range, 2.5–16.77).Conclusions: Systemic pemetrexed plus cisplatin is active for MPeM. Disparity with the outcome of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) needs to receive more emphasis, since peritoneal mesothelioma has a 5-year survival rate of 50%.

Long-term acupuncture treatment has a multi-targeting regulation on multiple brain regions in rats with Alzheimer's disease: a positron emission tomography study.

The acute effect of acupuncture on Alzheimer's disease, i.e., on brain activation during treatment, has been reported. However, the effect of long-term acupuncture on brain activation in Alzheimer's disease is unclear. Therefore, in this study, we performed long-term needling at Zusanli (ST36) or a sham point (1.5 mm lateral to ST36) in a rat Alzheimer's disease model, for 30 minutes, once per day, for 30 days. The rats underwent 18F-fluorodeoxyglucose positron emission tomography scanning. Positron emission tomography images were processed with SPM2. The brain areas activated after needling at ST36 included the left hippocampus, the left orbital cortex, the left infralimbic cortex, the left olfactory cortex, the left cerebellum and the left pons. In the sham-point group, the activated regions were similar to those in the ST36 group. However, the ST36 group showed greater activation in the cerebellum and pons than the sham-point group. These findings suggest that long-term acupuncture treatment has targeted regulatory effects on multiple brain regions in rats with Alzheimer's disease.