Fluorine-18 Fluorodeoxyglucose Positron Emission Research Articles

Tc-99m-tamoxifen: A novel diagnostic imaging agent for estrogen receptor-expressing breast cancer patients

PURPOSE The aim of the study was to radiolabel, characterize, and perform in vitro and in vivo assessment of Technetium-99m (Tc-99m) tamoxifen for screening ER expressing lesions in breast cancer patients. METHODS In this study, tamoxifen has been radiolabeled with Tc-99m via Tc-99m-tricarbonyl core. The characterization and quality control tests of Tc-99m-tamoxifen were performed. In vitro recep- tor binding and blocking studies were performed in both positive control (MCF-7) and negative control cell lines (MDA-MB-231). Normal biodistribution studies were performed in female Wistar albino rats. The pilot clinical studies were performed in 4 ER-expressing breast cancer patients. Of the 4 patients, 1 was on tamoxifen therapy. All 4 patients had also undergone Fluorine-18 fluorodeoxyglucose (F-18-FDG) positron emission tomography/computed tomography. RESULTS Tamoxifen was radiolabeled with Tc-99m via Tc-99m-tricarbonyl core with more than 95% radio- chemical yield. Mass spectra showed a peak corresponding to the molecular weight of Tc-99m- tricarbonyl and Tc-99m-tamoxifen. The site of binding of Tc-99m-tricarbonyl with tamoxifen was determined by proton nuclear magnetic resonance. The Tc-99m-tamoxifen showed 30% binding with MCF-7 and only 1%-2% receptor binding with MDA-MB-231 cell lines. Also, the percentage of receptor binding was drastically reduced (up to 72%) when ER was saturated with 50 times the excess molar ratio of unlabeled tamoxifen. In a pilot patient study, Tc-99m-tamoxifen uptake was observed in primary and metastatic lesions. However, no uptake was observed in a patient who was on tamoxifen therapy. The uptake of F-18-FDG was noted in all the patients. CONCLUSION Tamoxifen was radiolabeled with an in-house-synthesized Tc-99m-tricarbonyl core. The radio- labeled complex has been characterized and evaluated for receptor specificity in in vitro and in vivo studies. Also, this is the first clinical study using Tc-99m-tamoxifen for imaging ER. More patients need to be evaluated to further explore the role of Tc-99m-tamoxifen in ER-expressing lesions.

Time-related aortic inflammatory response, as assessed with 18F-FDG PET/CT, in patients hospitalized with severely or critical COVID-19: the COVAIR study

AimArterial involvement has been implicated in the coronavirus disease of 2019 (COVID-19). Fluorine 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) imaging is a valuable tool for the assessment of aortic inflammation and is a predictor of outcome. We sought to prospectively assess the presence of aortic inflammation and its time-dependent trend in patients with COVID-19. MethodsBetween November 2020 and May 2021, in this pilot, case-control study, we recruited 20 patients with severe or critical COVID-19 (mean age of 59 ± 12 years), while 10 age and sex-matched individuals served as the control group. Aortic inflammation was assessed by measuring 18F-FDG uptake in PET/CT performed 20-120 days post-admission. Global aortic target to background ratio (GLA-TBR) was calculated as the sum of TBRs of ascending and descending aorta, aortic arch, and abdominal aorta divided by 4. Index aortic segment TBR (IAS-TBR) was designated as the aortic segment with the highest TBR. ResultsThere was no significant difference in aortic 18F-FDG PET/CT uptake between patients and controls (GLA-TBR: 1.46 [1.40-1.57] vs. 1.43 [1.32-1.70], respectively, P = 0.422 and IAS-TBR: 1.60 [1.50-1.67] vs. 1.50 [1.42-1.61], respectively, P = 0.155). There was a moderate correlation between aortic TBR values (both GLA and IAS) and time distance from admission to 18F-FDG PET-CT scan (Spearman’s rho = − 0.528, P = 0.017 and Spearman’s rho = − 0.480, p = 0.032, respectively). Patients who were scanned less than or equal to 60 days from admission (n = 11) had significantly higher GLA-TBR values compared to patients that were examined more than 60 days post-admission (GLA-TBR: 1.53 [1.42-1.60] vs. 1.40 [1.33-1.45], respectively, P = 0.016 and IAS-TBR: 1.64 [1.51-1.74] vs. 1.52 [1.46-1.60], respectively, P = 0.038). There was a significant difference in IAS- TBR between patients scanned ≤ 60 days and controls (1.64 [1.51-1.74] vs. 1.50 [1.41-1.61], P = 0.036). ConclusionThis is the first study suggesting that aortic inflammation, as assessed by 18F-FDG PET/CT imaging, is increased in the early post COVID phase in patients with severe or critical COVID-19 and largely resolves over time. Our findings may have important implications for the understanding of the course of the disease and for improving our preventive and therapeutic strategies.

Brain Mechanism of Acupuncture Treatment of Chronic Pain: An Individual-Level Positron Emission Tomography Study.

ObjectiveAcupuncture has been shown to be effective in the treatment of chronic pain. However, their neural mechanism underlying the effective acupuncture response to chronic pain is still unclear. We investigated whether metabolic patterns in the pain matrix network might predict acupuncture therapy responses in patients with primary dysmenorrhea (PDM) using a machine-learning-based multivariate pattern analysis (MVPA) on positron emission tomography data (PET).MethodsForty-two patients with PDM were selected and randomized into two groups: real acupuncture and sham acupuncture (three menstrual cycles). Brain metabolic data from the three special brain networks (the sensorimotor network (SMN), default mode network (DMN), and salience network (SN)) were extracted at the individual level by using PETSurfer in fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) data. MVPA analysis based on metabolic network features was employed to predict the pain relief after treatment in the pooled group and real acupuncture treatment, separately.ResultsPaired t-tests revealed significant alterations in pain intensity after real but not sham acupuncture treatment. Traditional mass-univariate correlations between brain metabolic and alterations in pain intensity were not significant. The MVPA results showed that the brain metabolic pattern in the DMN and SMN did predict the pain relief in the pooled group of patients with PDM (R2 = 0.25, p = 0.005). In addition, the metabolic pattern in the DMN could predict the pain relief after treatment in the real acupuncture treatment group (R2 = 0.40, p = 0.01).ConclusionThis study indicates that the individual-level metabolic patterns in DMN is associated with real acupuncture treatment response in chronic pain. The present findings advanced the knowledge of the brain mechanism of the acupuncture treatment in chronic pain.

An evaluation of the response to neoadjuvant chemotherapy for osteosarcoma of extremities: PERCIST versus RECIST 1.1 criteria after long-term follow-up.

The aim of this study was to compare the recent Positron emission tomography (PET) Response Criteria in Solid Tumors (PERCIST) and Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria for evaluating the response of osteosarcoma to neoadjuvant chemotherapy of the extremities. We retrospectively reviewed patients with osteosarcoma of the extremities who received neoadjuvant chemotherapy and then surgical resection at Peking University People's Hospital. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and magnetic resonance imaging (MRI) were performed prior to chemotherapy and before surgical resection. Therapeutic response was assessed separately by the PERCIST and RECIST 1.1 criteria. The association between the data acquired by the PERCIST and RECIST 1.1 criteria was then analyzed by Wilcoxon's signed-rank test. The association between the PERCIST criteria and the pathological necrosis rate was analyzed by Fisher's exact test. Finally, the impact of a range of clinicopathological factors on overall survival (OS) and event-free survival (EFS) was analyzed by Cox proportional hazards regression. We recruited 68 patients with a median follow-up of 74months (range 45-102months). The evaluations resulting from the RECIST 1.1 and PERCIST criteria were significantly different (p = 0.000). Only two responders were identified according to the RECIST 1.1 criteria. However, 34 responders were identified by the PERCIST criteria. Data arising from the PERCIST criteria were in accordance with the pathological necrosis rate. Survival analysis showed that metastasis at diagnosis, poor pathological response, and disease progression (according to the RECIST 1.1 or PERCIST criteria) were all associated with a poor prognosis (p < 0.05). Our data indicate that the PERCIST criteria are significantly more sensitive than RECIST 1.1 criteria to identify more responders when evaluating the response of osteosarcoma to neoadjuvant chemotherapy.

Comprehensive nutrient consumption estimation and metabolic profiling during ketogenic diet and relationship with myocardial glucose uptake on FDG-PET.

The ketogenic diet (KD) is standard-of-care to achieve myocardial glucose suppression (MGS) for assessing inflammation using fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET). As KD protocols remain highly variable between centres (including estimation of nutrient intake by dietary logs for adequacy of dietary preparation), we aimed to assess the predictive utility of nutrient intake in achieving MGS. Nineteen healthy participants underwent short-term KD, with FDG-PET performed after 1 and 3 days of KD (goal carbohydrate intake <20 g/day). Nutrient consumption was estimated from dietary logs using nutrition research software. The area under receiver operating characteristics (AUROC) of macronutrients (carbohydrate, fat, and protein intake) for predicting MGS was analysed. The association between 133 nutrients and 4 biomarkers [beta-hydroxybutyrate (BHB), non-esterified fatty acids, insulin, and glucagon] with myocardial glucose uptake was assessed using mixed effects regression with false discovery rate (FDR) correction. Median (25th-75th percentile) age was 29 (25-34) years, 47% were women, and 42% were non-white. Median (25th-75th percentile) carbohydrate intake (g) was 18.7 (13.1-30.7), 16.9 (10.4-28.7), and 21.1 (16.6-29.0) on Days 1-3. No macronutrient intake (carbohydrate, fat, or protein) predicted MGS (c-statistic 0.45, 0.53, 0.47, respectively). Of 133 nutrients and 4 biomarkers, only BHB was associated with myocardial glucose uptake after FDR correction (corrected P-value 0.003). During highly supervised, short-term KD, approximately half of patients meet strict carbohydrate goals. Yet, in healthy volunteers, dietary review does not provide reassurance for adequacy of myocardial preparation since no clear thresholds for carbohydrate or fat intake reliably predict MGS.

Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography, Hodgkin's Lymphoma, COVID Vaccination, and Appropriate Investigation Time.

Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography, Hodgkin's Lymphoma, COVID Vaccination, and Appropriate Investigation Time.

Role of Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in Detection of Portal Vein Tumor Thrombosis in Hepatocellular Carcinoma

A 56 year old gentleman with no known comorbidities presented with pain abdomen for 1 month. Triphasic CECT abdomen showed features of cirrhosis with surface irregularities, fissural widening and volume redistribution changes in the liver. Segment VII of liver showed an arterial enhancing lesion measuring 4.2 x 3.5cm showing washout in delayed phase. In view of BCLC A stage with Child Pugh B7, ablation was planned. Before proceeding with ablation, in view of very high alpha-fetoprotein (AFP) level of 9836 ng/mL, he was advised for metastatic evaluation with 18F-FDG PET-CT. The PET scan showed abnormal heterogeneous increased FDG uptake in segment VII of liver (SUV Max 4.7) with arterial enhancement and washout suggestive of metabolically active hepatocellular carcinoma. Also seen was an abnormal linear increased FDG uptake in right branch of portal vein (SUV Max 4.8) which was suggestive of portal vein invasion. In view of portal vein tumor thrombus, ablation procedure was deferred for the patient. Role of PET scan in HCC with vascular invasion is not yet defined. Poor specificity of FDG PET is the major hindrance in establishing PET scan as diagnostic tool for vascular invasion. In small segment invasion when CECT is not able to differentiate between tumour versus bland thrombus PET scan may be significant tool to differentiate between bland thrombus and tumour thrombus. Vascular invasion confirmation have treatment related and prognostic significance. There is a need for a prospective study evaluating the prognostic significance of PET scan based diagnosis of vascular invasion.

Comparative study between 18F-FDG PET scan and conventional CT in assessment of non-small cell lung cancer patients after treatment

Background: Lung cancer is one of the most common malignancies worldwide. Hence, timely diagnosis and accurate staging of the carcinoma as well as strict follow up is critical for better prognosis. Imaging studies play a key role in post-treatment follow up of patients with lung cancer. Positron emission tomography (PET) scanning has developed as an important tool in the multi-disciplinary management of lung cancer. The combination of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and computed tomography (CT) has a great impact on the diagnosis, staging, and hence on the follow up of lung cancer patients compared to conventional CT study only. Methods: A retrospective comparative study conducted on 15 patients histopathologically proven to have NSCLC. Conclusion: 18F-FDG PET scan had a superior role in monitoring tumor turn over in case of no appreciable time interval changes in its size according to the CT.

Staging canine patients with appendicular osteosarcoma utilizing fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography compared to whole body computed tomography.

Few studies have investigated the diagnostic performance of fluorine-18-fluorodeoxyglucose (18 F-FDG) positron emission tomography/computed tomography (PET/CT) for staging veterinary patients with appendicular osteosarcoma. The purpose of this study was to evaluate the efficacy of 18 F-FDG-PET/CT compared to whole-body CT (WBCT) for staging canine patients with appendicular osteosarcoma. The 18 F-FDG-PET/CT imaging studies of 66 dogs with appendicular osteosarcoma were anonymized and separated into two detached studies (one with whole body pre- and post-contrast CT images and the other with the whole body pre- and post-contrast CT images with the associated 18 F-FDG-PET overlay). Image assessment was performed retrospectively by five board-certified veterinary radiologists. The radiologists were instructed to assign a predefined categorical score (1-4) to each pre-designated anatomic region based on a devised lesional scoring system. A score of 1 was normal, 2 abnormal but not neoplastic, 3 abnormal and concerning for neoplasia, and 4 abnormal, most likely neoplastic. Overall, the likelihood of detection of '3 or 4' was found to be significantly higher with 18 F-FDG PET/CT when compared to WBCT after adjusting for the effect of evaluator and the subject. Most significantly, 13 osseous lesions concerning for metastasis (scored 3-4) were identified in 10/66 dogs by at least one reviewer on 18 F-FDG PET/CT, which were not identified by any reviewer on WBCT. Additionally, four comorbid neoplastic lesions were identified with 18 F-FDG PET/CT and not with WBCT. The results of this study suggest that 18 F-FDG PET/CT is more efficacious in detecting metastatic and comorbid neoplastic lesions compared to WBCT in dogs with appendicular osteosarcoma.

Correlation Between CT Features of Active Tuberculosis and Residual Metabolic Activity on End-of-Treatment FDG PET/CT in Patients Treated for Pulmonary Tuberculosis.

Patients who complete a standard course of anti-tuberculous treatment (ATT) for pulmonary tuberculosis and are declared cured according to the current standard of care commonly have residual metabolic activity (RMA) in their lungs on fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PER/CT) imaging. RMA seen in this setting has been shown to be associated with relapse of tuberculosis. The routine clinical use of FDG PET/CT imaging for treatment response assessment in tuberculosis is hindered by cost and availability. CT is a more readily available imaging modality. We sought to determine the association between CT features suggestive of active tuberculosis and RMA on FDG PET/CT obtained in patients who completed a standard course of ATT for pulmonary tuberculosis. We prospectively recruited patients who completed a standard course of ATT and declared cured based on negative sputum culture. All patients had FDG PET/CT within 2 weeks of completing ATT. We determined the presence of RMA on FDG PET images. Among the various lung changes seen on CT, we considered the presence of lung nodule, consolidation, micronodules in tree-in-bud pattern, FDG-avid chest nodes, and pleural effusion as suggestive of active tuberculosis. We determine the association between the presence of RMA on FDG PET and the CT features of active tuberculosis. We include 75 patients with a mean age of 36.09 ± 10.49 years. Forty-one patients (54.67%) had RMA on their FDG PET/CT while 34 patients (45.33%) achieved complete metabolic response to ATT. There was a significant association between four of the five CT features of active disease, p < 0.05 in all cases. Pleural effusion (seen in two patients) was the only CT feature of active disease without a significant association with the presence of RMA. This suggests that CT may be used in lieu of FDG PET/CT for treatment response assessment of pulmonary tuberculosis.

Gender-Related Differences in Regional Cerebral Glucose Metabolism in Normal Aging Brain.

Objectives: This study was aimed to investigate the gender-related differences of regional cerebral glucose metabolism in healthy people along the age using 18F-FDG PET/CT.Methods: We recruited 344 healthy volunteers, including 217 males and 127 females (age range: 40–89 years old). All subjects underwent fluorine-18 fluorodeoxyglucose(18F-FDG) positron emission tomography (PET). All the data were divided into four groups for every 10 years old. Each participant was carefully screened from PET, MR, and other examinations in order to exclude the abnormalities, such as neurodegenerative or psychiatric disorders, alcohol/abuse, cerebral vascular disorders, metabolic diseases like diabetes mellitus and hyperthyroidism, and other systemic malignancies. The 40–50 years old group was set as the baseline group. Statistical parametric mapping (SPM) analysis was employed to illustrate the differences among groups.Results: Compared to the baseline group, whether in a cohort or different gender groups, the decrease of brain glucose metabolism was shown in the bilateral frontal lobe, anterior cingulate gyrus, and the bilateral temporal lobe. In males, the regions of decreased metabolism were bilateral frontal lobe, caudate nucleus, and cingulate gyrus, whereas that of females were left occipital lobe, cerebellum, and the thalamus. However, the overall decrease of brain metabolism in men and women began from the age of 60s, an aggravated decrease from 70s was only observed in males.Conclusion: (1) An obviously decreased brain metabolism was found from 60 years old, especially in the bilateral frontal lobe, bilateral temporal lobe, and inferior cingulate gyrus; (2) We found specific brain metabolic differences between genders, including the caudate nucleus region in males and the occipital lobe region in females; and (3) The aging trend is different between genders.

Evaluation of Lung Glucose Uptake with Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/CT in Patients with Pulmonary Arterial Hypertension and Pulmonary Hypertension Due to Left Heart Disease.

Aim: Previous studies have demonstrated increased glucose uptake by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in lung parenchyma in animal models or small pulmonary arterial hypertension (PAH) cohorts. However, it is not well known whether increased FDG uptake in the lung is a unique phenomenon in PAH or whether elevated pulmonary artery pressure (PAP) induces FDG uptake. Methods and results: Nineteen patients with PAH, 8 patients with pulmonary hypertension due to left heart disease (PH-LHD), and 14 age matched control subjects were included. All PH patients underwent right heart catheterization and FDG-PET. The mean standard uptake value (SUV g/mL) of FDG in each lung was obtained and average values of both lungs were calculated as mean lung FDG SUV. The correlation between hemodynamics and mean lung FDG SUV was also analyzed in PH patients. Mean PAP (mPAP) was not significantly different between PAH and PH-LHD (45±11 vs 43±5 mmHg, p=0.51). PAH patients demonstrated significantly increased mean lung FDG SUV compared with PH-LHD and controls (PAH: 0.76±0.26 vs PH-LHD: 0.51±0.12 vs controls: 0.53±0.16, p=0.0025). The mean lung FDG SUV did not correlate with mPAP either in PAH or PH-LHD. Conclusion: PAH is associated with increased lung FDG uptake indicating increased glucose utilization in the lung. This may represent metabolic shift to glycolysis and/or active inflammation in the remodeled pulmonary vasculature, and is observed to a greater extent in PAH than in patients with PH secondary to LHD and control subjects without PH.

Disseminated Kaposi sarcoma with osseous metastases in patients with HIV infection. Case report

Background. Kaposi sarcoma is a low-grade vascular tumor affecting blood and lymphatic vessels associated with the human herpes virus type 8 (HHV-8). As a rule, the skin of the lower extremities is involved in the process first of all, and then other organs and lymph nodes are involved. There are 4 various types of the disease with different clinical picture: the classic, the endemic, the epidemic and immunosuppression subtype. The epidemic subtype is the most common and has the most aggressive course, with specific lesions of a multiple kind, including the skin, mucous membrane layers, the lymph nodes, the gastrointestinal tract, the lungs and the spleen. Osseous metastases are extremely rare.&#x0D; Aim. Show the case of Kaposi sarcoma with osseous metastases in patient with the human immunodeficiency virus (HIV) infection.&#x0D; Results. We observed a 43-year-old patient with HIV infection and stage 4b Kaposi sarcoma against the background of the irregular antiretroviral therapy in the progression stages. The duration of the anamnesis was 32 months. The clinical debut of the cancer process was noted with skin lesions on the shoulder. Histological and immunohistochemical analysis of skin biopsies showed the morphological picture of Kaposi sarcoma. HHV-8 was expressed in tumor cells. During the endoscopic examination the lesions of oral mucosa, stomach and proximal colon were confirmed morphologically, and spiral computed tomography of the chest revealed the lesions in the lungs. On this point, the patients received oxaliplatin-based chemotherapy and aetoposidum for 6 months and against the background of this treatment we observed the disease progression associated with the involvement of the retroperitoneal lymph nodes, the left adrenal gland and the penis. Circumcision was performed in the case associated with the involvement of the penis. The treatment was continued. The lytic left iliac bone lesion, the retroperitoneal lymph nodes, the iliac lymph node groups, as well as the left inguinal lymph nodes, the left adrenal gland and the lungs were characterized by a high F-18 FDG uptake after 3 months of the treatment, according to the results of Fluorine-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography combined with computed tomography (PET/CT).&#x0D; Conclusion. Kaposi sarcoma in patients with HIV infection had an aggressively course with disseminated skin lesions and internal organ involvement, including bones as showed in this clinical case. In this case, the axial skeleton was more commonly involved. PET/CT is a diagnostic imaging method in the differential diagnosis and determination of the prevalence of the cancer process.

Three cases of GFAP astrocytopathy, one with bilateral ovarian teratoma

AbstractGlial fibrillary acidic protein (GFAP) astrocytopathy is a novel autoimmune meningoencephalomyelitis. Case 1 is a 26–year‐old (yo) woman with a bilateral ovarian teratoma. She presented neck stiffness, hyperreflexia, bilateral postural tremor, and urinary retention. Three courses of a methylprednisolone pulse and subsequent enucleation of the bilateral ovarian teratoma improved her neurological symptoms with no recurrence. Case 2 is a 46‐year‐old man who showed infectious‐like symptoms with elevated creatine kinase. Case 3 is a 76‐year‐old man with preceding weight loss, a hyperintensity lesion in the hypothalamus, and increased uptake of the spinal cord, assessed by Fluorine18 fluorodeoxyglucose positron emission tomography (18F‐FDG PET). We compared the clinical features of the present three cases with previous reports. Consciousness disturbance, neck stiffness, tremors, and urinary dysfunction were observed in all three cases. These findings suggest widespread damage of the brain and spinal cord.

Clinical outcomes of patients with isolated cardiac sarcoidosis confirmed by clinical diagnostic criteria

BackgroundAlthough isolated cardiac sarcoidosis (CS) is not uncommon, little is known about the prognosis. We aimed to clarify clinical features and clinical outcomes in patients with isolated CS. MethodsTwo-hundred eighty-six patients with suspected CS were enrolled. Systemic CS (SCS) was diagnosed by histological or clinical confirmation of sarcoidosis according to the guidelines. Isolated CS was diagnosed by histological or clinical confirmation in the heart alone. The endpoint was cardiac death, hospitalization for heart failure, or fatal ventricular arrhythmia. ResultsTwenty-one patients were diagnosed with isolated CS, and 63 were diagnosed with SCS. The frequencies of diagnostic criteria, such as high-grade atrioventricular block or fatal ventricular arrhythmia, basal thinning of the ventricular septum, left ventricular contractile dysfunction, positive myocardial uptake of gallium-67 citrate scintigraphy or fluorine-18 fluorodeoxyglucose positron emission tomography, and delayed contrast enhancement of cardiac magnetic resonance, were higher or equivalent in patients with isolated CS, compared to those with SCS. Over a median follow-up of 31 months (range: 1–175 months), cardiac death, hospitalization for heart failure, or fatal ventricular arrhythmia occurred in 14 (67%) patients with isolated CS, 24 (38%) patients with SCS, and 63 (31%) patients without CS. The rate of cardiac events was higher in patients with isolated CS (log-rank test, p = 0.01). Cox proportional hazard analysis showed that isolated CS, age, and New York Heart Association functional class were independently associated with cardiac events. ConclusionsPatients with isolated CS have clinical features compatible with SCS, and have cardiac events at a higher rate.

Role of 18F-FDG PET/CT Radiomics Features in the Differential Diagnosis of Solitary Pulmonary Nodules: Diagnostic Accuracy and Comparison between Two Different PET/CT Scanners.

The aim of this retrospective study was to investigate the ability of 18 fluorine-fluorodeoxyglucose positron emission tomography/CT (18F-FDG-PET/CT) metrics and radiomics features (RFs) in predicting the final diagnosis of solitary pulmonary nodules (SPN). We retrospectively recruited 202 patients who underwent a 18F-FDG-PET/CT before any treatment in two PET scanners. After volumetric segmentation of each lung nodule, 8 PET metrics and 42 RFs were extracted. All the features were tested for significant differences between the two PET scanners. The performances of all features in predicting the nature of SPN were analyzed by testing three classes of final logistic regression predictive models: two were built/trained through exploiting the separate data from the two scanners, and the other joined the data together. One hundred and twenty-seven patients had a final diagnosis of malignancy, while 64 were of a benign nature. Comparing the two PET scanners, we found that all metabolic features and most of RFs were significantly different, despite the cross correlation being quite similar. For scanner 1, a combination between grey level co-occurrence matrix (GLCM), histogram, and grey-level zone length matrix (GLZLM) related features presented the best performances to predict the diagnosis; for scanner 2, it was GLCM and histogram-related features and metabolic tumour volume (MTV); and for scanner 1 + 2, it was histogram features, standardized uptake value (SUV) metrics, and MTV. RFs had a significant role in predicting the diagnosis of SPN, but their accuracies were directly related to the scanner.

Current update on imaging for pancreatic neuroendocrine neoplasms.

Pancreatic neuroendocrine neoplasms (panNEN) are a heterogeneous group of tumors with differing pathological, genetic, and clinical features. Based on clinical findings, they may be categorized into functioning and nonfunctioning tumors. Adoption of the 2017 World Health Organization classification system, particularly its differentiation between grade 3, well-differentiated pancreatic neuroendocrine tumors (panNET) and grade 3, poorly-differentiated pancreatic neuroendocrine carcinomas (panNEC) has emphasized the role imaging plays in characterizing these lesions. Endoscopic ultrasound can help obtain biopsy specimen and assess tumor margins and local spread. Enhancement patterns on computed tomography (CT) and magnetic resonance imaging (MRI) may be used to classify panNEN. Contrast enhanced MRI and diffusion-weighted imaging have been reported to be useful for characterization of panNEN and quantifying metastatic burden. Current and emerging radiotracers have broadened the utility of functional imaging in evaluating panNEN. Fluorine-18 fluorodeoxyglucose positron emission tomography (PET)/CT and somatostatin receptor imaging such as Gallium-68 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid–octreotate PET/CT may be useful for improved identification of panNEN in comparison to anatomic modalities. These new techniques can also play a direct role in optimizing the selection of treatment for individuals and predicting tumor response based on somatostatin receptor expression. In addition, emerging methods of radiomics such as texture analysis may be a potential tool for staging and outcome prediction in panNEN, however further investigation is required before clinical implementation.

Fluorine-18 fluorodeoxyglucose positron emission tomography-based textural features for prediction of event prone carotid atherosclerotic plaques

BackgroundTexture analysis has been increasingly used in the field of positron emission tomography (PET)/computed tomography (CT) imaging with Fluorine-18 fluorodeoxyglucose (18F-FDG), aiming at assessing tumor heterogeneity. The purpose of the present study is to examine the feasibility of performing texture analysis in carotid arteries, investigate the value of textural features as predictors of potential plaque vulnerability using as reference standards histological and immunohistochemical data and compare their performance with conventional uptake measurements. Methods67 different 18F-FDG PET-based textural features were extracted from carotid images of 21 patients with high-grade carotid stenosis undergoing endarterectomy. To identify the more reliable predictors, univariate logistic regression analysis was performed. The accuracy was satisfactory in case of an Area Under the Receiver Operating Characteristic (ROC) curve (AUC) ≥ 0.80. ResultsFirst measure of information correlation (AUC = 0.87, P < 0.001), large zone low gray level emphasis (AUC = 0.87, P < 0.001), and normalized run length non-uniformity (AUC = 0.84, P < 0.001) were the most optimal textural features for identifying characteristics of plaque vulnerability based on histological analysis. Addition of textural features to target-to-background ratio (TBR) (AUC = 0.74, P = 0.031) resulted in an AUC = 0.92 (P < 0.001), however, this did not reach statistical significance (Pdiff = 0.09). Intensity histogram standard deviation (AUC = 0.87, P < 0.001) and joint variance (AUC = 0.81, P = 0.001) were the most efficient features for signal differential in relation to immunohistochemical findings and provided incremental value compared to TBR (Pdiff = 0.02). ConclusionTexture analysis can be applied in 18F-FDG PET carotid imaging providing valuable information for plaque characterization.

Role of FDG-PET CT in differentiating adenocarcinomas from squamous cell carcinomas of the lung

Abstract Background Lung cancer is the leading cause of cancer related deaths worldwide. The combination of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and computed tomography (CT) has a great impact on the diagnosis, staging, and hence on the treatment plan and follow up of lung cancer patients. Maximum standardized uptake value (SUVmax) is a semi-quantitative index which is easily performed and the most widely used quantitative parameter for the analysis of 18F-FDG PET images and for the estimation of metabolic activity. Objective to investigate the role of PET/ CT to differentiate between adenocarcinomas (AC) and squamous cell carcinomas (SCC) as the most common lung cancer by comparing their FDG uptake measured in the form of SUVmax. Methods A retrospective observational study, conducted at Ain Shams University Hospitals- Radiology Department patients diagnosed with non-small cell lung cancer (NSCLC) and histopathologically proved to be adenocarcinoma or squamous cell carcinoma. All were investigated using PET/CT scans in the period between June 2017 to September 2019. SUVmax of the lesion were measured and statistically analyzed compared with the histopathological type. Results A total of 30 patients were evaluated with the age ranging from 31 to 81 years old, the mean was 56.9 years (SD ± 11.53). Among them 25 patients (83.3%) were males and 5 patients (16.7%) were females. Out of the 30 NSCLC patients included in the study, 18 patients (60%) were histopathologically diagnosed as AC and 12 patients (40%) were histopathologically diagnosed as SCC. The mean SUVmax of the 30 NSCLC lesions was 15.02±8.4 (range: 2-32.8).The mean SUVmax of AC lesions was 12.4±7.55 (range: 2-32.8), while the mean SUVmax of SCC lesions was 18.95±8.3 (range: 3.7-30.77). The mean SUVmax of lesions in patients with SCC was significantly higher than that of patients with AC using Wilcoxon-Mann-Whitney test (P = 0.04). Conclusion SCC of the lung has higher SUVmax than AC of the lung and it can be used to differentiate between them using PET/CT.

Haemophagocytic lymphohistiocytosis in a patient with familial Mediterranean fever and miliary tuberculosis: a case report

Haemophagocytic lymphohistiocytosis (HLH) is a lethal complication of several infections, especially viral origin. Mycobacterium tuberculosis infection can also lead to HLH, yet it is an uncommon trigger. Considering the role of increased cytokines in HLH, autoinflammatory conditions, such as familial Mediterranean fever (FMF), might contribute to its development. Nevertheless, the possible relationship between FMF and HLH has been suggested only in some case reports. We present a case of FMF who admitted to the hospital with consitutional symptoms and chest pain regarding to recurrent pericarditis. On a blood test, pancytopenia and elevated acute phase reactants were seen. Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography demonstrated positive FDG uptake sites on both the right and left surrenal glands, the visceral layer of pericard, and reactive lymphadenomegalies at multiple mediastinal regions. Bone marrow biopsy revealed haemophagocytosis. Methylprednisolone treatment was initiated. Despite immunosuppressive treatment, clinical and biochemical parameters deteriorated; thus, a thorax computed tomography was executed. Findings were consistent with miliary tuberculosis infection. M. tuberculosis was detected in blood culture and bronchoalveolar lavage culture material. Also, bone marrow and surrenal biopsy material revealed necrotising caseating granuloma.