Fluorodeoxyglucose Positron Emission Tomography Research Articles

The value of 18F-fluorodeoxyglucose positron emission tomography-based radiomics in non-small cell lung cancer

ABSTRACT Currently, the second most commonly diagnosed cancer in the world is lung cancer, and 85% of cases are non-small cell lung cancer (NSCLC). With growing knowledge of oncogene drivers and cancer immunology, several novel therapeutics have emerged to improve the prognostic outcomes of NSCLC. However, treatment outcomes remain diverse, and an accurate tool to achieve precision medicine is an unmet need. Radiomics, a method of extracting medical imaging features, is promising for precision medicine. Among all radiomic tools, 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET)-based radiomics provides distinct information on glycolytic activity and heterogeneity. In this review, we collected relevant literature from PubMed and summarized the various applications of 18F-FDG PET-derived radiomics in improving the detection of metastasis, subtyping histopathologies, characterizing driver mutations, assessing treatment response, and evaluating survival outcomes of NSCLC. Furthermore, we reviewed the values of 18F-FDG PET-based deep learning. Finally, several challenges and caveats exist in the implementation of 18F-FDG PET-based radiomics for NSCLC. Implementing 18F-FDG PET-based radiomics in clinical practice is necessary to ensure reproducibility. Moreover, basic studies elucidating the underlying biological significance of 18F-FDG PET-based radiomics are lacking. Current inadequacies hamper immediate clinical adoption; however, radiomic studies are progressively addressing these issues. 18F-FDG PET-based radiomics remains an invaluable and indispensable aspect of precision medicine for NSCLC.

An Analysis of Age-Related Body Composition Changes and Metabolic Patterns in Korean Adults Using FDG-PET/CT Health Screening Data.

F-18-fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) can be used to measure bone mineral density (BMD), cross-sectional muscle area (CSMA), Hounsfield units (HU) of liver and muscle, subcutaneous adipose tissue (SAT), abdominal visceral adipose tissue (VAT), and glucose metabolism. The present study aimed to identify age-related changes in body composition and glucose metabolism in Korean using opportunistic FDG-PET/CT imaging. We analyzed FDG-PET/CT, clinical history, and laboratory data abstracted from the medical records of patients who underwent health screening at a single institute between 2017 and 2022. In total, 278 patients were included in the analysis (male:female=140:138). Age and body mass index were positively correlated in female, but negatively correlated in male. BMD decreased with age more in female, and CSMA decreased with age more in male. Muscle HU decreased with age for both sexes. In female, SAT and VAT increased with age; and in male, SAT decreased slightly while VAT remained stable. Muscle glucose metabolism showed no association with age in male but increased with age in female. CSMA correlated positively with BMD overall; and positively correlated with VAT and SAT in male only. In female only, both SAT and VAT showed negative correlations with glucose metabolism and correlated positively with muscle glucose metabolism. Liver HU values were inversely correlated with VAT, especially in female; and positively correlated with muscle glucose metabolism in female only. FDG-PET/CT demonstrated distinct patterns of age-related changes in body composition and glucose metabolism, with significant differences between sexes.

Acetyl-DL-leucine in two individuals with REM sleep behavior disorder improves symptoms, reverses loss of striatal dopamine-transporter binding and stabilizes pathological metabolic brain pattern—case reports

Isolated REM Sleep Behavior Disorder (iRBD) is considered a prodrome of Parkinson’s disease (PD). We investigate whether the potentially disease-modifying compound acetyl-DL-leucine (ADLL; 5 g/d) has an effect on prodromal PD progression in 2 iRBD-patients. Outcome parameters are RBD-severity sum-score (RBD-SS-3), dopamine-transporter single-photon emission computerized tomography (DAT-SPECT) and metabolic “Parkinson-Disease-related-Pattern (PDRP)”-z-score in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). After 3 weeks ADLL-treatment, the RBD-SS-3 drops markedly in both patients and remains reduced for >18 months of ADLL-treatment. In patient 1 (female), the DAT-SPECT putaminal binding ratio (PBR) decreases in the 5 years pretreatment from normal (1.88) to pathological (1.22) and the patient’s FDG-PET-PDRP-z-score rises from 1.72 to 3.28 (pathological). After 22 months of ADLL-treatment, the DAT-SPECT-PBR increases to 1.67 and the FDG-PET-PDRP-z-score stabilizes at 3.18. Similar results are seen in patient 2 (male): his DAT-SPECT-PBR rises from a pretreatment value of 1.42 to 1.72 (close to normal) and the FDG-PET-PDRP-z-score decreases from 1.02 to 0.30 after 18 months of ADLL-treatment. These results support exploration of whether ADLL may have disease-modifying properties in prodromal PD.

Patterns of glucose hypometabolism can help differentiate FTLD-FET from other types of FTLD.

FTLD-FET is a newly described subtype of frontotemporal lobar degeneration (FTLD characterized by pathologic inclusions of FET proteins: fused in sarcoma (FUS), Ewing sarcoma, and TATA-binding protein-associated factor 2N (TAF15)). Severe caudate volume loss on MRI has been linked to FTLD-FUS, yet glucose hypometabolism in FTLD-FET has not been studied. We assessed [18F] fluorodeoxyglucose PET (FDG-PET) hypometabolism in FTLD-FET subtypes and compared metabolism to FTLD-tau and FTLD-TDP. We retrospectively reviewed medical records of 26 autopsied FTLD patients (six FTLD-FET, ten FTLD-Tau, and ten FTLD-TDP) who had completed antemortem FDG-PET. We evaluated five regions, caudate nucleus, medial frontal cortex, lateral frontal cortex, and medial temporal using a 0-3 visual rating scale and validated our findings quantitatively using CORTEX-ID suite Z scores. Of the six FTLD-FET cases (three females) with median age at onset = 36, three were atypical FTLD-U (aFTLD-U) and three were neuronal intermediate filament inclusion disease (NIFID). bvFTD was the most common presentation. Four of the six FTLD cases (3 aFTLD-U + 1 NIFID) showed prominent caudate hypometabolism relatively early in the disease course. FTLD-tau and FTLD-TDP did not show early prominent caudate hypometabolism. Hypometabolism in medial and lateral temporal cortex was associated with FTLD-TDP, while FTLD-tau had normal-minimal regional metabolism. Prominent caudate hypometabolism, especially early in the disease course, appears to be a hallmark feature of the aFTLD-U subtype of FTLD-FET. Assessing caudate and temporal hypometabolism on FDG-PET will help to differentiate FTLD-FET from FTLD-tau and FTLD-TDP.

Double-hit primary central nervous system lymphoma with histogenetically proven bone marrow infiltration: a case report and a review of the literature.

Double-hit lymphoma (DHL) formerly referred to high-grade B-cell lymphoma with concurrent MYC and BCL2 or BCL6 rearrangements, however, the updated 2022 World Health Organization Classification (5th edition online) excludes those with MYC and BCL 6 rearrangements from the high-grade category. DHL confined to the central nervous system (CNS), known as double-hit primary CNS lymphoma (DH-PCNSL), is rare with poorly understood clinical features. Here, we report a case of a 64-year-old man with multiple brain tumors diagnosed with DH-PCNSL who showed bone marrow (BM) infiltration early in the clinical course. The histological diagnosis was high-grade B-cell lymphoma with MYC and BCL6 rearrangements. Fluorodeoxyglucose positron emission tomography (FDG-PET) revealed no abnormal accumulation except in the CNS. The patient received whole-brain radiotherapy following the failure of high-dose methotrexate. After completion of radiotherapy, the patient developed thrombocytopenia, and BM biopsy showed infiltration of DHL cells, which were not detected by repeated FDG-PET. This is the first report of DH-PCNSL where identical gene rearrangements were confirmed in both the resected CNS tumor and BM tissue. Patients with DH-PCNSL require careful follow-up because they may be at a potential risk of BM infiltration, which may be undetectable by FDG-PET, particularly early in the disease course.

Deep learning with uncertainty estimation for automatic tumor segmentation in PET/CT of head and neck cancers: impact of model complexity, image processing and augmentation

Objective. Target volumes for radiotherapy are usually contoured manually, which can be time-consuming and prone to inter- and intra-observer variability. Automatic contouring by convolutional neural networks (CNN) can be fast and consistent but may produce unrealistic contours or miss relevant structures. We evaluate approaches for increasing the quality and assessing the uncertainty of CNN-generated contours of head and neck cancers with PET/CT as input. Approach. Two patient cohorts with head and neck squamous cell carcinoma and baseline 18F-fluorodeoxyglucose positron emission tomography and computed tomography images (FDG-PET/CT) were collected retrospectively from two centers. The union of manual contours of the gross primary tumor and involved nodes was used to train CNN models for generating automatic contours. The impact of image preprocessing, image augmentation, transfer learning and CNN complexity, architecture, and dimension (2D or 3D) on model performance and generalizability across centers was evaluated. A Monte Carlo dropout technique was used to quantify and visualize the uncertainty of the automatic contours. Main results. CNN models provided contours with good overlap with the manually contoured ground truth (median Dice Similarity Coefficient: 0.75–0.77), consistent with reported inter-observer variations and previous auto-contouring studies. Image augmentation and model dimension, rather than model complexity, architecture, or advanced image preprocessing, had the largest impact on model performance and cross-center generalizability. Transfer learning on a limited number of patients from a separate center increased model generalizability without decreasing model performance on the original training cohort. High model uncertainty was associated with false positive and false negative voxels as well as low Dice coefficients. Significance. High quality automatic contours can be obtained using deep learning architectures that are not overly complex. Uncertainty estimation of the predicted contours shows potential for highlighting regions of the contour requiring manual revision or flagging segmentations requiring manual inspection and intervention.

PET imaging of synaptic vesicle glycoprotein 2 subtype A for neurological recovery in ischemic stroke.

[18F]SynVesT-1 is a novel radiopharmaceutical for assessing synaptic density in vivo. This study aims to investigate the potential of [18F]SynVesT-1 positron emission tomography (PET) in evaluating neurological recovery in the rat model of ischemic stroke, and to compare its performance with [18F]FDG PET. Sprague-Dawley rats were subjected to photothrombotic cerebral infarction, and safinamide was administered intraperitoneally from day 3 to day 14 post-stroke to alleviate neurological deficits. Cylinder test and forelimb placing test were performed to assess the neurological function. MRI, [18F]SynVesT-1 PET/CT and [18F]FDG PET/CT imaging were used to evaluate infarct volume, synaptic density, and cerebral glucose metabolism pre- and post-treatment. [18F]SynVesT-1 and [18F]FDG PET images were compared using Statistical Parametric Mapping (SPM) and region of interest (ROI)-based analysis. Post-mortem histological analysis was performed to validate PET images. Safinamide treatment improved behavioral outcomes in stroke-damaged rats. Both [18F]SynVesT-1 and [18F]FDG PET detected stroke-induced injury, with the injured region being significantly larger in [18F]FDG PET than in [18F]SynVesT-1 PET. Compared with the saline group, radiotracer uptake in the injured area significantly increased in [18F]SynVesT-1 PET after safinamide treatment, whereas no notable change was observed in [18F]FDG PET. Additionally, [18F]SynVesT-1 PET imaging showed a better correlation with neurological function recovery than [18F]FDG PET. Post-mortem analysis revealed increased neuronal numbers, synaptic density, and synaptic neuroplasticity, as well as decreased glia activation in the stroke-injured area after treatment. [18F]SynVesT-1 PET effectively quantified spatiotemporal dynamics of synaptic density in the rat model of stroke, and showed different capabilities in detecting stroke injury and neurological recovery compared with [18F]FDG PET. The utilization of [18F]SynVesT-1 PET holds promise as a potential non-invasive biomarker for evaluating ischemic stroke in conjunction with [18F]FDG PET.

11C]Methionine PET vs. [18F]Fluorodeoxyglucose PET Whole-body Imaging to Determine the Extent of Methionine-addiction Compared to Glucose-addiction of Primary and Metastatic Cancer of the Trunk in Patients.

Positron emission tomography (PET) is an important imaging modality, especially in oncology. [18F]fluorodeoxyglucose PET (FDG-PET) is the most used cancer PET imaging. However, since the elevated glucose use by cancers, termed the Warburg effect, is usually only moderate, FDG often does not provide a strong or well-delineated signal. Malignancies have a stronger addiction to methionine, known as the Hoffman effect, and thus [11C]methionine PET (MET-PET) has demonstrated superiority over FDG-PET in gliomas and other brain tumors. Our team is pioneering the use of MET-PET for tumors of the trunk for both better detection of cancer and to determine candidates for methionine-restriction therapy. The present study provides examples of cancers of organs in the trunk in which MET-PET outperforms FDG-PET in detecting and delineating primary and metastatic cancer. In all cases, MET-PET and FDG-PET were performed simultaneously. An evaluation of the images was conducted by a nuclear medicine physician. Four cases, including prostate, bladder, esophageal, and breast cancer demonstrated the superiority of MET-PET compared to FDG-PET. MET-PET can out-perform FDG PET for accurate detection of primary and metastatic cancer in the trunk and can determine the extent of methionine addiction of cancer, thereby indicating whether cancer patients can benefit from methionine-restriction therapy.

18F-FDG-PET/MR imaging to monitor disease activity in large vessel vasculitis

Disease-monitoring in large vessel vasculitis (LVV) is challenging. Simultaneous 18F-fluorodeoxyglucose positron emission tomography with magnetic resonance imaging (PET/MRI) provides functional assessment of vascular inflammation alongside high-definition structural imaging with a relatively low burden of radiation exposure. Here, we investigate the ability of PET/MRI to monitor LVV disease activity longitudinally in a prospective cohort of patients with active LVV. We demonstrate that both the PET and MRI components of the scan can distinguish active from inactive disease using established quantification methods. Using logistic-regression modelling of PET/MRI metrics, we devise a novel PET/MRI-specific Vasculitis Activity using MR PET (VAMP) score which is able to distinguish active from inactive disease with more accuracy than established methods and detects changes in disease activity longitudinally. These findings are evaluated in an independent validation cohort. Finally, PET/MRI improves clinicians’ assessment of LVV disease activity and confidence in disease management, as assessed via clinician survey. In summary, PET/MRI may be useful in tracking disease activity and assessing treatment-response in LVV. Based on our findings, larger, prospective studies assessing PET/MRI in LVV are now warranted.

Poor sleep quality is associated with decreased regional brain glucose metabolism in healthy middle-aged adults

Sleep disturbance is associated with the development of neurodegenerative disease. We aimed to address the effects of sleep quality on brain glucose metabolism measured by 18F-Fl uorodeoxyglucose (18F-FDG) positron emission tomography (PET) in healthy middle-aged adults. A total of 378 healthy men (mean age: 42.8±3.6 years) were included in this study. Participants underwent brain 18F-FDG PET and completed the Korean version of the Pittsburgh Sleep Quality Index (PSQI-K). Additionally, anthropometric measurements were obtained. PETs were spatially normalized to MNI space using PET templates from SPM5 with PMOD. The Automated Anatomical Labeling 2 atlas was used to define regions of interest (ROIs). The mean uptake of each ROI was scaled to the mean of the global cortical uptake of each individual and defined as the standardized uptake value ratio (SUVR). After the logarithmic transformation of the regional SUVR, the effects of the PSQI-K on the regional SUVR were investigated using Bayesian hierarchical modeling. Brain glucose metabolism of the posterior cingulate, precuneus, and thalamus showed a negative association with total PSQI-K scores in the Bayesian model ROI-based analysis. Voxel-based analysis using statistical parametric mapping revealed a negative association between the total PSQI-K scores and brain glucose metabolism of the precuneus, postcentral gyrus, posterior cingulate, and thalamus. Poor sleep quality is negatively associated with brain glucose metabolism in the precuneus, posterior cingulate, and thalamus. Therefore, the importance of sleep should not be overlooked, even in healthy middle-aged adults.

Contribution of alpha-synuclein pathology to cerebral glucose metabolism in patients with amnestic MCI.

The in vivo detection of mixed Alzheimer's disease (AD) and α-synuclein (αSyn) pathology is important for clinical management and prognostic stratification. We investigated the contribution of αSyn pathology, detected by cerebrospinal fluid (CSF) seed amplification assay (αSyn SAA), on [18F]-fluorodeoxyglucose positron emission tomography (FDG PET) pattern in subjects with amnestic mild cognitive impairment (aMCI). We included 562 aMCI participants and 204 cognitively normalcontrols (CN) with available αSyn SAA and cerebral metabolic rate for glucose utilization (rCMRgl) data. 24% of aMCI cases were positive (+) for CSF αSyn SAA. Compared to CN, both αSyn+ and negative (-) aMCI participants showed reductions in rCMRgl within AD typical regions. αSyn+ aMCI had lower rCMRgl within AD and dementia with Lewy bodies (DLB) typical regions compared to αSyn- aMCI, even after stratification according to the CSF AT(N) system. αSyn pathology contributes to a distinct FDG PET pattern in aMCI. αSyn pathology can be detected in vivo by CSF αSyn SAA. We investigated the FDG PET pattern in aMCI patients with CSF αSyn SAA positivity. αSyn+ aMCI showed a marked brain hypometabolism in AD and DLB typical regions.

Management of acute myocarditis: a systematic review of clinical practice guidelines and recommendations.

The management of acute myocarditis (AM) is addressed in multiple clinical guidelines. We systematically reviewed current guidelines developed by national and international medical organizations on the management of AM to aid clinical practice. Publications in MEDLINE, EMBASE and Cochrane were identified between 1 January 2013 and 12 April 2024. Additionally, the websites of relevant organizations and the Guidelines International Network, Guideline Central, and NHS knowledge and library hub were reviewed. Two reviewers independently screened titles and abstracts, two reviewers assessed the rigour of guideline development, and one reviewer extracted the recommendations. Two of the three guidelines identified showed good rigour of development. Those rigorously developed agreed on the definition of AM, sampling serum troponin as part of the workflow for AM, testing for B-type natriuretic peptides in heart failure, key diagnostic imaging in the form of cardiovascular magnetic resonance, coronary angiography to exclude significant coronary disease, indications for endomyocardial biopsy (EMB), and indications for immunosuppression and advanced treatment options. Discrepancies exist in sampling creatine kinase-myocardial bound as a marker of myocardial injury, indications for EMB, and indications for immunosuppression and treatment of uncomplicated AM. Evidence is lacking for the use of 18F-Fluorodeoxyglucose Positron Emission Tomography for myocardial imaging, exercise restriction, follow-up measures and genetic testing, and there are few high-quality randomized trials to support treatment recommendations. Recommendations for management of AM in the guidelines have largely been developed from expert opinion rather than trial data.

Effects of Glucose Intolerance on Physiological Accumulation in Salivary Glands and Palatine Tonsils During 18F-Fluorodeoxyglucose Positron Emission Tomography.

We evaluated the effects of chronic hyperglycemia on physiological accumulation in salivary glands and tonsils during18F-fluorodeoxyglucose positron emission tomography (FDG-PET/CT). 12,738 patients underwent whole-body FDG-PET/CT in our institute during the study period. Of these, the case group comprised 777 patients with a blood glucose (BG) level >140 mg/dL; the control group comprised an equal number of randomly selected age- and sex-matched individuals with a BG level <110 mg/dL. Within the case group, the diabetic subgroup was defined as individuals with a BG level >200 mg/dL. Visual assessment and accumulation intensity among tissues were compared between the case and control groups, including (1) the mean difference in maximum standardized uptake value (SUVmax), (2) the difference in the proportion of patients with visible tissues on maximum intensity projection images, and (3) differences between the diabetic subgroup and the control group. Parotid, submandibular, sublingual, and tonsillar tissues all showed significantly lower SUVmax in the case group than in the control group. The proportions of individuals with visible uptake in the parotid and tonsillar tissues and in the sublingual gland were significantly smaller in the case group than in the control group. Tonsillar uptake was observed in more than 90% of individuals in the control group but in two-thirds of patients in the diabetic subgroup. Accumulation in the parotid and submandibular glands was visible in approximately 80% of individuals in the control groupbut only half of patients in the diabetic subgroup. Physiological accumulation in salivary glands and tonsils is significantly reduced among individuals with hyperglycemia or diabetes.

Association between thermogenic brown fat and genes under positive natural selection in circumpolar populations

BackgroundAdaptation to cold was essential for human migration across Eurasia. Non-shivering thermogenesis through brown adipose tissue (BAT) participates in cold adaptation because some genes involved in the differentiation and function of BAT exhibit signatures of positive natural selection in populations at high latitudes. Whether these genes are associated with the inter-individual variability in BAT thermogenesis remains unclear. In this study, we evaluated the potential associations between BAT activity and single nucleotide polymorphisms (SNPs) in candidate gene regions in East Asian populations.MethodsBAT activity induced by mild cold exposure was measured in 399 healthy Japanese men and women using fluorodeoxyglucose-positron emission tomography and computed tomography (FDG-PET/CT). The capacity for cold-induced thermogenesis and fat oxidation was measured in 56 men. Association analyses with physiological traits were performed for 11 SNPs at six loci (LEPR, ANGPTL8, PLA2G2A, PLIN1, TBX15-WARS2, and FADS1) reported to be under positive natural selection. Associations found in the FDG-PET/CT population were further validated in 84 healthy East Asian men and women, in whom BAT activity was measured using infrared thermography. Associations between the SNP genotypes and BAT activity or other related traits were tested using multiple logistic and linear regression models.ResultsOf the 11 putative adaptive alleles of the six genes, two intronic SNPs in LEPR (rs1022981 and rs12405556) tended to be associated with higher BAT activity. However, these did not survive multiple test comparisons. Associations with lower body fat percentage, plasma triglyceride, insulin, and HOMA-IR levels were observed in the FDG-PET/CT population (P < 0.05). Other loci, including TBX15-WARS2, which is speculated to mediate cold adaptation in Greenland Inuits, did not show significant differences in BAT thermogenesis.ConclusionsOur results suggest a marginal but significant association between LEPR SNPs. However, robust supporting evidence was not established for the involvement of other loci under positive natural selection in cold adaptation through BAT thermogenesis in East Asian adults. Given the pleiotropic function of these genes, factors other than cold adaptation through BAT thermogenesis, such as diet adaptation, may contribute to positive natural selection at these loci.

Clinicoradiological and neuropathological evaluation of primary progressive aphasia

BackgroundPrimary progressive aphasia (PPA) defines a group of neurodegenerative disorders characterised by language decline. Three PPA variants correlate with distinct underlying pathologies: semantic variant PPA (svPPA) with transactive response DNA-binding...

Successful pancreatectomy after conversion-intended chemotherapy using gemcitabine and nab-paclitaxel for unresectable adenosquamous carcinoma of the pancreas: a case report

BackgroundAdenosquamous carcinoma of the pancreas (ASCP) accounts for only 1–4% of all pancreatic exocrine cancers and has a particularly poor prognosis. The efficacy of chemotherapy for ASCP remains unknown because of the small number of cases, and few studies have evaluated conversion-intended chemotherapy.Case presentationA 76-year-old woman was referred to our hospital because of epigastric pain and nausea. A preoperative contrast-enhanced multidetector row computed tomography (MDCT) scan revealed a 17 × 17 mm low-density tumor with an ill-defined margin at the arterial phase in the pancreatic head. The tumor involved the common hepatic artery, left hepatic artery bifurcated from the common hepatic artery, and gastroduodenal artery, and was in contact with the portal vein. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed an uptake in the pancreatic head but no evidence of distant metastasis. The tumor was diagnosed as an adenocarcinoma of the pancreatic head and staged unresectable because the common and left hepatic arteries were involved. Hence, the patient underwent seven courses of conversion-intended chemotherapy using gemcitabine and nab-paclitaxel for pancreatic ductal adenocarcinoma over 7 months. After chemotherapy, the tumor shrank to 10 × 10 mm on contrast-enhanced MDCT. Consequently, the boundary between the tumor and major vessels of the common and left hepatic arteries and the portal vein became clear, and the involvement of the arteries with the tumor was evaluated to be released. The contact of the tumor to the portal vein also reduced to less than half the circumference of the portal vein. FDG-PET showed decreased accumulation in the tumor. Hence, the tumor was judged resectable, and pancreaticoduodenectomy was performed. The tumor and major blood vessels were easily dissected and R0 resection was achieved. The patient experienced no major complications and was discharged on postoperative day 28. The tumor was revealed as ASCP via pathological examination. The patient is alive and recurrence-free seven months after surgery. This is the first report of successful R0 resection for an initially unresectable ASCP following conversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen. ConclusionsConversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen may be effective for ASCP.

An aggressive Cushing's syndrome originating from a rare thymic neuroendocrine tumor, controlled successfully with fluconazole and octreotide therapy before surgery.

Cushing's syndromes (CSs) due to the thymic neuroendocrine tumors are rarely seen. Here, a case of ectopic CS originating from an atypical neuroendocrine tumor has been presented. A 49-year-old woman was hospitalized with symptoms of fatigue, chest pressure, dyspnea, muscle weakness, and resistant hypertension. There was marked hyperpigmentation in the whole-body surface suggestive of adrenocorticotropic hormone (ACTH) excess and there were physical features of CS. There was deep hypokalemia. Basal hormone profile, dexamethasone suppression tests, midnight cortisol, and 24-hour urine cortisol levels were suggestive of ectopic CS. The pituitary magnetic resonance imaging revealed a 5 mm cystic lesion and the patient refused inferior petrosal sinus sampling. Thorax computerized tomography showed an anterior mediastinal mass. A fluorodeoxyglucose-positron emission tomography showed the same mediastinal lesion (suvmax: 11.4), and no other tumor focus was detected. There was an aggressive cortisol excess causing acute respiratory distress syndrome, making it difficult to perform the surgery. We immediately started fluconazole and octreotide therapy and were successful in lowering the cortisol level. Then a complete resection of the tumor had been able to be surgically performed and tumor cells showed strong cytoplasmic immunopositivity with ACTH. A definitive diagnosis of "ACTH secreting atypical thymic carcinoid tumor" was rendered based on the histopathological and immunohistochemical features. There was only surrounding vessel invasion, and no lymphoid or other organ metastases were detected. As there were surrounding vessel invasions, a two-cycle regimen cisplatin-etoposide chemotherapy and radiotherapy were employed. After surgical and medical therapy, the cortisol and ACTH levels turned to normal. The patient is in biochemical and clinical remission and has no tumor recurrence yet. Ectopic ACTH-producing thymic carcinoids are rare but life-threatening tumors because of the underlying malignancy and severe hypercortisolemia. It is important to consider this disease and perform appropriate treatment at the right time. Today, surgery is the standard therapeutic modality if it is possible to perform, but there is not a clear and constant recommendation for nonsurgical therapeutic modalities. Further studies are needed for the optimal treatment strategies.

Omics-derived biological modules reflect metabolic brain changes in Alzheimer's disease.

Brain glucose hypometabolism, indexed by the fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) imaging, is a metabolic signature of Alzheimer's disease (AD). However, the underlying biological pathways involved in these metabolic changes remain elusive. Here, we integrated [18F]FDG-PET images with blood and hippocampal transcriptomic data from cognitively unimpaired (CU, n=445) and cognitively impaired (CI, n=749) individuals using modular dimension reduction techniques and voxel-wise linear regression analysis. Our results showed that multiple transcriptomic modules are associated with brain [18F]FDG-PET metabolism, with the top hits being a protein serine/threonine kinase activity gene cluster (peak-t(223)=4.86, P value<0.001) and zinc-finger-related regulatory units (peak-t(223)=3.90, P value<0.001). By integrating transcriptomics with PET imaging data, we identified that serine/threonine kinase activity-associated genes and zinc-finger-related regulatory units are highly associated with brain metabolic changes in AD. We conducted an integrated analysis of system-based transcriptomics and fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) at the voxel level in Alzheimer's disease (AD). The biological process of serine/threonine kinase activity was the most associated with [18F]FDG-PET in the AD brain. Serine/threonine kinase activity alterations are associated with brain vulnerable regions in AD [18F]FDG-PET. Zinc-finger transcription factor targets were associated with AD brain [18F]FDG-PET metabolism.

Application effect of 18F-FDG PET/CT technique in diagnosis and prognosis evaluation of lymphoma

The objective of the study was to research diagnostic and prognostic values of 18F fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) in patients with diffuse large B-cell lymphoma (DLBCL). The diagnostic sensitivity (Sen) of PET/CT (94.75 %) was remarkably higher than 83.56 % of B-US. Age ≥ 65 years old, maximum focal diameter ≥5 cm, clinical stages III-IV, systemic symptoms, increased lactate dehydrogenase level, high modified international prognostic index score, Ecog score ≥1, B-cell lymphoma 2 (Bcl-2) gene, MYC protein expression rate, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were all factors that influenced the recurrence or progression of DLBCL. With higher MTV and TLG, patients would have a greater probability of recurrence or progression. 18F-FDG PET/CT showed a high diagnostic Sen in lymphoma lesions, and could accurately guide clinical staging. Combined with clinical parameters, laboratory indicators, and metabolic parameters, prognostic indicators of patients could be evaluated more accurately.

Outcome analysis of autologous stem cell transplantation in refractory and relapsed Hodgkin lymphoma: Insights from a North African single-institution study.

172 Background: The standard therapy for primary refractory or relapsed Hodgkin lymphoma (HL) involves the administration of high-dose chemotherapy followed by autologous stem cell transplantation (HDC/ASCT). Nevertheless, several risk factors may influence survival outcomes. We assessed outcomes of patients in this setting who underwent HDC/ASCT by performing survival analysis and studying prognostic factors affecting survival. Methods: We conducted a single-institution retrospective analysis of patients with relapsed/refractory HL who received HDC/ASCT between January 2018 and December 2022. Patients’ status evaluation before ASCT was performed by Fluorodeoxyglucose-Positron Emission Tomography (FDG-PET) Scan and Computed Tomography (CT) Scan. The used conditioning regimen was BEAM (Carmustine, Etoposide, Cytarabine, and Melphalan). The primary endpoints were progression-free survival (PFS) and overall survival (OS). Survival analysis was performed using the Kaplan-Meier method, and survival differences between groups were assessed using the Log-Rank test. Results: Thirty-five patients diagnosed with relapsed/refractory HL were included in the study. Among them, 26 patients (74%) had refractory disease, while 9 patients (26%) relapsed following completion of first-line chemotherapy. All patients were treated with HDC/ASCT. Prior to ASCT, 30 patients underwent assessment using FDG-PET Scan, while CT Scan was employed for evaluation in 5 patients. Twenty-three patients (66%) were in complete remission, 8 patients (23%) were in partial remission, and 4 patients (11%) had progressive disease. With a median follow-up of 24.36 months after transplantation, 28 patients (80%) were in remission, 6 patients (17%) had disease progression, and one patients died of septic shock. The 2-year PFS and OS rates for the total population were 85.4% and 97.1%, respectively. Response to first-line chemotherapy did not have a substantial impact on prognosis, as evidenced by a 2-year PFS rate of 76.2% vs. 88.9% (p=0.88) and a 2-year OS rate of 100% vs. 96.2% (p=0.56) for patients with relapsed and refractory disease, respectively. The 2-year PFS and OS rates for patients receiving autograft during complete remission, partial response, and tumor progression were 93.8% vs. 87.5% vs. 50% (p=0.005), respectively; and 95.7% vs. 100% vs. 100%, respectively (p=0.77). Patients who had negative pre-transplant PET-Scans demonstrated a 2-year PFS rate of 92.9% vs. 64.8% for those with positive PET-scans (p=0.004). Conclusions: The findings of our study affirm the established practice of HDC/ASCT for individuals facing relapsed/refractory HL. The disease status at transplant and the pre-transplant PET-Scan status prove to be crucial factors in predicting patients’ outcomes, while response to first-line chemotherapy did not influence prognosis.