18F-Fluorodeoxyglucose positron emission tomography/computed tomography imaging reveals the protective effect of docosahexaenoic acid on glucose metabolism by reducing brain 27-hydroxycholesterol.

Total cholesterol (TC) and the cholesterol oxidation product 27-hydroxycholesterol (27-OHC) are both increased in the elderly. Accumulating evidence has linked 27-OHC to glucose metabolism in the brain, while docosahexaenoic acid (DHA) has been shown to positively regulate the 27-OHC levels. However, it is unclear whether DHA may affect glucose metabolism in the brain by regulating 27-OHC levels. In this study, we hypothesized that DHA supplementation would modulate TC levels and reduce 27-OHC levels, thereby improving brain glucose metabolism in SAMP8 mice. The mice were assigned into the Control group and DHA dietary supplementation group. The study evaluated cholesterol levels, 27-OHC levels, and glucose metabolism in the brain. The results showed that DHA supplementation decreased serum levels of TC, low-density lipoprotein cholesterol (LDL-C), and increased levels of high-density lipoprotein cholesterol (HDL-C); and improved the glucose-corrected standardized uptake value of cortex, hippocampus, and whole brain regions in SAMP8 mice. In conclusion, supplementation of DHA could regulate the cholesterol composition and reduce the level of 27-OHC, thereby improving brain glucose metabolism in SAMP8 mice.

Limbic Network Derangement Mediates Unawareness of Apathy in Mild Cognitive Impairment due to Alzheimer's Disease: Clues from [18F]FDG PET Voxel-Wise Analysis.

Background: Discrepancy between caregiver and patient assessments of apathy in mild cognitive impairment (MCI) is considered an index of apathy unawareness, independently predicting progression to AD dementia. However, its neural underpinning are uninvestigated. Objective: To explore the [18F]FDG PET-based metabolic correlates of apathy unawareness measured through the discrepancy between caregiver and patient self-report, in patients diagnosed with MCI. Methods: We retrospectively studied 28 patients with an intermediate or high likelihood of MCI-AD, progressed to dementia over an average of two years, whose degree of apathy was evaluated by means of the Apathy Evaluation Scale (AES) for both patients (PT-AES) and caregivers (CG-AES). Voxel-based analysis at baseline was used to obtain distinct volumes of interest (VOIs) correlated with PT-AES, CG-AES, or their absolute difference (DISCR-AES). The resulting DISCR-AES VOI count densities were used as covariates in an inter-regional correlation analysis (IRCA) in MCI-AD patients and a group of matched healthy controls (HC). Results: DISCR-AES negatively correlated with metabolism in bilateral parahippocampal gyrus, posterior cingulate cortex, and thalamus, PT-AES score with frontal and anterior cingulate areas, while there was no significant correlation between CG-AES and brain metabolism. IRCA revealed that MCI-AD patients exhibited reduced metabolic/functional correlations of the DISCR-AES VOI with the right cingulate gyrus and its anterior projections compared to HC. Conclusions: Apathy unawareness entails early disruption of the limbic circuitry rather than the classical frontal-subcortical pathways typically associated with apathy. This reaffirms apathy unawareness as an early and independent measure in MCI-AD, marked by distinct pathophysiological alterations.

Diagnostic performance of 18F­FDG PET/CT vs. 18F­NaF PET/CT in breast cancer with bone metastases: An indirect comparative meta­analysis.

Breast cancer remains the leading cause of cancer-related death in women, with 5-year survival rates of as high as 90% for patients with early-stage breast cancer without metastasis, falling to 10% once bone metastases (BM) occur. Currently, there is no cure for breast cancer with BM. However, appropriate treatment can extend survival and improve patients' quality of life. Therefore, it is important to accurately evaluate the presence of BM in patients with breast cancer. The present meta-analysis evaluated the diagnostic performance of 18F-FDG and 18F-NaF as PET/CT tracers for breast cancer-associated BM. The present study aimed to compare the diagnostic performance of fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomographs (PET/CT) and 18F-sodium fluoride (18F-NaF) PET/CT in patients with breast cancer and BM. The PubMed and Embase databases were searched for English literature on the diagnostic performance of 18F-FDG PET/CT and 18F-NaF PET/CT for breast cancer BM, and two authors independently extracted data. All included studies presented data that could be used to construct a 2×2 contingency table. The methodological quality of the selected studies was assessed using QUADAS-2, and forest plots were generated based on the sensitivity and specificity of 18F-FDG PET/CT and 18F-NaF PET/CT in the diagnosis of BM associated with breast cancer. A total of 14 articles were identified, including eight on the analysis of 18F-FDG PET/CT, five on 18F-NaF PET/CT and one on both. The studies on 18F-FDG PET/CT and 18F-NaF PET/CT included 530 and 270 patients, respectively. The pooled sensitivities were 0.88 [95% confidence interval (95% CI), 0.76-0.94] for 18F-FDG PET/CT and 0.98 (95% CI, 0.92-1.00) for 18F-NaF PET/CT, and the pooled specificities were 0.99 (95% CI, 0.97-1.00) and 0.91 (95% CI: 0.76-0.97), respectively. The area under the summary receiver operating characteristic curve for both 18F-FDG PET/CT and 18F-NaF PET/CT was 0.99 (95% CI, 0.98-1.00). Lesion-based analysis using 18F-FDG PET/CT was performed for 909 lesions, with a sensitivity of 0.84 (95% CI, 0.67-1.00) and specificity of 1.00 (95% CI, 0.98-1.00). Compared with 18F-FDG PET/CT, 18F-NaF PET/CT showed higher sensitivity (98 vs. 88%) but lower specificity (91 vs. 99%), although the difference between methods was not statistically significant. In conclusion, the results of the present study indicated that 18F-NaF PET/CT and 18F-FDG PET/CT are both accurate methods for the detection of BM in patients with breast cancer, and have comparable diagnostic accuracy.

Arterial inflammation on [18F]FDG PET/CT in melanoma patients treated with and without immune checkpoint inhibitors: CHECK-FLAME I.

BACKGROUND AND AIMS: Immune checkpoint inhibitors (ICIs) revolutionized cancer treatment. However, ICIs may increase the immune response to non-tumor cells, possibly resulting in increased arterial inflammation, raising the risk of atherosclerotic events. Nevertheless, malignancies may induce a pro-inflammatory state and the association between ICIs and arterial inflammation remains to be clarified. This study aims to assess differences in increase in arterial inflammation between patients with advanced melanoma treated with ICIs compared to a control group without ICIs. METHODS: Patients with advanced melanoma who underwent [18F]FDG PET/CT scans at baseline, 6 months (T1) and 18 months (T2) were included in this retrospective observational study. Arterial inflammation was evaluated in eight segments by calculating the target-to-background ratio (TBR). The primary study outcome was the difference in increase in mean TBRmax between patients treated with and without ICIs. RESULTS: We included 132 patients of whom 72.7 % were treated with ICIs. After exclusion for the use of anti-inflammatory medication, patients treated with ICIs showed a significant increase in mean TBRmax between baseline and T1 from 1.29 ± 0.12 to 1.33 ± 0.13 (p = 0.017), while in the control group, no change in mean TBRmax (1.30 ± 0.12 to 1.28 ± 0.10, p = 0.22) was observed (p = 0.027). During longer follow-up, mean TBRmax remained stable in both groups. Arterial inflammation increased significantly after ICI therapy in patients without active inflammation (p < 0.001) and in patients without calcifications (p = 0.013). CONCLUSIONS: A significant increase in arterial inflammation as measured on [18F]FDG PET/CT was observed in patients with advanced melanoma treated with ICIs only in the first six months after initiation of therapy, whereas no changes were observed in the control group. Moreover, arterial inflammation was mainly increased in patients without pre-existing inflammatory activity and with non-calcified lesions.

Prognostic significance of diffuse increased fluorine-18-fluorodeoxyglucose (18F-FDG) uptake within the reticuloendothelial system in lymphoma patients.

Background: As constituents of the reticuloendothelial system, the spleen and bone marrow (BM) have been recognized as integral components of the systemic inflammatory response in cancer contexts, thereby serving as predictive indicators for assessing cancer prognosis. Fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) has attained widespread utilization for staging, assessing treatment response, and prognostication in lymphoma patients. Several investigations have proposed that focal increased 18F-FDG uptake in the BM or spleen may correlate with malignant involvement in lymphoma. However, scant data exist regarding the implications of diffuse BM and splenic uptake. This study aimed to explore the relationships between metabolic parameters of the spleen and BM on 18F-FDG PET/CT and inflammatory markers, and to assess their prognostic value in patients with lymphoma. Methods: A retrospective analysis was conducted on 118 patients newly diagnosed with malignant lymphoma, who underwent 18F-FDG PET/CT and exhibited diffuse increased splenic or BM uptake in 18F-FDG PET/CT imaging. The mean standardized uptake value (SUV) of the spleen, BM, and liver was calculated. The association between metabolic variables and systemic inflammatory markers was investigated, and the prognostic significance of clinicopathological and PET parameters was assessed using overall survival (OS) and progression-free survival (PFS). Results: A statistically significant correlation was found between the spleen-to-liver SUV ratio (SLR) and inflammatory markers such as C-reactive protein (r=0.264, P=0.007) and platelet-to-lymphocyte ratio (r=0.227, P=0.021). No significant correlation was observed between BM-to-liver SUV ratio (BLR) and hematologic parameters, while concordance analysis revealed a fair agreement between BLR and bone marrow biopsy (BMB) (Cohen's Kappa-κ =0.271, P=0.002). In patients with aggressive non-Hodgkin lymphoma, both SLR [P=0.017, HR 2.715, 95% confidence interval (CI): 0.875-8.428] and BLR (P=0.044, HR 0.795, 95% CI: 0.348-1.813) were significantly linked to OS, while SLR (P=0.019, HR 2.223, 95% CI: 1.139-4.342) emerged as a significant prognostic factor for PFS. Conclusions: This study highlighted that diffuse increased splenic 18F-FDG uptake in lymphoma patients was closely associated with inflammation, whereas diffuse BM uptake was likely attributable to BM infiltration rather than inflammatory changes. Furthermore, both parameters held promise as prognostic indicators for patients with aggressive lymphoma.

IMPeTUs parameters correlate with clinical features in newly diagnosed multiple myeloma.

Objectives: To investigate the correlations between IMPeTUs-based 18 F-FDG PET/CT parameters and clinical features in patients with newly diagnosed multiple myeloma (MM). Materials and methods: PET/CT were analysed according to the IMPeTUs criteria. We correlated these PET/CT parameters with known clinically relevant features, bone marrow plasma cell (BMPC) infiltration rate and the presence of cytogenetic abnormalities. Results: A total of 149 patients (86 males, 63 females; mean age, 59.9 ± 9.7 years) were included. Bone marrow metabolic state correlated with the most clinical features including hemoglobin (rho=-0.23, p=0.004), FLC ratio (rho=0.24, p=0.005), ß2 M (rho=0.28, p=0.001), CRP (rho=0.25, p=0.003), serum calcium (rho=0.22, p=0.02), serum creatinine (rho=0.24, p=0.004) and BMPC (rho=0.21, p=0.003). Besides, the level of hemoglobin was significant lower (0.043), and the levels of FLC ratio (0.037), ß2 M (p=0.024), CRP (p=0.05), and BMPC (p=0.043) were significant higher in patients having hypermetabolism in limbs and ribs. Hottest bone lesion Deauville criteria had a moderate correlation with CRP (rho=0.27, p=0.001) and serum calcium (rho=0.25, p=0.01). Conclusion: Several IMPeTUs-based PET/CT parameters showed significant correlations with clinical features reflecting disease burden and biology, suggesting that these new criteria can be used in the risk stratification in MM patients.

Evaluation of prognostic risk factors of triple-negative breast cancer with 18F-FDG PET/CT parameters, clinical pathological features and biochemical indicators.

Introduction: Breast cancer is a heterogeneous disease comprising various molecular subtypes, including Luminal A, Luminal B, human epidermal growth factor receptor-2 (HER2) positive, and triple negative types, each with distinct biological characteristics and behaviors. Triple negative breast cancer (TNBC) remains a particularly challenging subtype worldwide. Our study aims to evaluate whether Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) parameters, clinical pathological features, and biochemical indicators serve as prognostic risk factors for TNBC. Additionally, we explore correlations between biochemical indicators and 18F-FDG PET/CT parameters. Methods: We conducted a retrospective analysis of 95 TNBC patients who underwent preoperative 18F-FDG PET/CT examinations at Tianjin Medical University Cancer Institute and Hospital from 2013 to 2018. Collected data included 18F-FDG PET/CT parameters, clinical and pathological features, and biochemical indicators. We used Kaplan-Meier survival analysis and multivariate Cox regression analysis to evaluate associations between 18F-FDG PET/CT parameters/biochemical indicators and disease free survival (DFS)/overall survival (OS). The log-rank test determined significant differences in survival curves, and the Spearman correlation coefficient analyzed correlations between quantitative variables. Visualization and analysis were performed using R packages. Results: Among 95 TNBC patients, mean standardized uptake value (SUVmean) was significantly correlated with DFS. Fasting blood glucose (FBG), α- L-fucosylase (AFU) and Creatine kinase (CK) were independent predictors of DFS, while Precursor albumin (PALB) and CK were independent predictors of OS. FBG showed correlations with SUVpeak and SUVmean, and CK was correlated with peak standardized uptake value (SUVpeak). Our results indicated that 18F-FDG PET/CT parameters and biochemical indicators may constitute a new prognostic model for TNBC patients post-surgery. Discussion: We found that SUVmean, FBG, AFU and CK are predictive factors for DFS in TNBC patients post-surgery, while PALB and CK are predictive factors for OS, which prompts us to pay more attention to these indicators in clinical practice. Also 18F-FDG PET/CT parameters and biochemical indicators have potential utility in constituting a new prognostic model for TNBC patients post-surgery.

Applicability and performance of 18F-FDG PET-based modalities for whole-body cancer screening: a systematic review and meta-analysis.

PURPOSE: Screening tests are the cornerstone for early detection and optimal management of cancers. Most of the present cancer-screening tests are intrusive, time-consuming, and specifically target a particular anatomical site or cancer type. Only a few studies have reported the objective measures of 18F-FDG PET-based cancer screening in asymptomatic individuals. This review and meta-analysis is an attempt to assess the applicability and performance of 18F-FDG PET-based modalities for whole-body cancer screening. MATERIALS AND METHODS: The systematic review and meta-analysis were performed following PRISMA guidelines. Literature searches in PubMed, Scopus, and Embase were conducted using relevant MeSH terms and keywords, for articles published in the last 2 decades (2000-2022). Pooled estimates of diagnostic test accuracy-including sensitivity, specificity, positive-likelihood ratio, negative-likelihood ratio, and hierarchical summary ROC (HSROC) curve were generated using bivariate random-effects meta-analysis. RESULTS: Seventeen studies were included in the systematic review and 13 studies were deemed eligible for meta-analysis. The mean estimates of pooled sensitivity, specificity, positive-likelihood ratio, negative-likelihood ratio, and Odds ratio using 18F-FDG PET with a 95% confidence interval were 0.47 (0.25-0.69), 0.97 (0.95-0.98), 18.8 (6.8-51.5), 0.45 (0.27-0.76), 41.0 (7.9-211.8) and for 18F-FDG PET/CT were 0.83 (0.75-0.88), 0.98 (0.97-0.99), 49.7 (29.2-84.5), 0.15 (0.8-0.28), 329.9 (125.0-870.8), respectively. Among screening modalities, 18F-FDG PET/CT had a higher accuracy i.e., the area under the HSROC curve (AUC): 0.91 (0.87-0.95) compared to 18F-FDG PET: 0.72 (0.61-0.82). CONCLUSION: This study demonstrates that currently 18F-FDG PET-based screening has limited applicability for population-based cancer-screening programs. However, it has a promising role as a combined screening strategy for at-risk individuals and allows for comprehensive diagnostic and prognostic evaluation in high-resource settings.

Androgen and Cortisol Cosecreting Adrenal Adenoma and Tuberculous Lymphadenitis.

The differential diagnosis between malignant and benign adrenal cortical tumors is challenging, and concurrent androgen and cortisol production should raise  suspicion of a malignant tumor. We present the case of a 36-year-old woman who exhibited pronounced hirsutism, clitoromegaly, and secondary amenorrhea. A contrast-enhanced computed tomography (CT) scan revealed a 35 × 27 mm right adrenal mass with unenhanced CT attenuation of 40 Hounsfield units (HUs). The mass exhibited absolute and relative washout rates of 50% and 28%, respectively, and was accompanied by a 25 × 20 mm adenopathy located in the hepatogastric space. Total testosterone was elevated by 247 ng/dL (8.56 nmol/L) (normal reference range, 10-75 ng/dL; 0.34-2.6 nmol/L). A 1-mg dexamethasone suppression test revealed an elevated serum morning cortisol concentration of 10.57 µg/dL (291.58 nmol/L) (reference range, <1.8 µg/dL; < 49.66 nmol/L). A fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) scan revealed increased uptake in both the adrenal mass and the adenopathy. Subsequently, the patient underwent an open right adrenalectomy and lymphadenectomy. Histological examination revealed the presence of an adrenal adenoma with myelolipomatous metaplasia, as well as a positive polymerase chain reaction (PCR) for Mycobacterium tuberculosis in the adenopathy.

Role of quantitative imaging biomarkers in an early FDG-PET/CT for detection of immune-related adverse events in melanoma patients: a prospective study.

BACKGROUND: To evaluate the role of the novel quantitative imaging biomarker (QIB) SUVX% of 18F-FDG uptake extracted from early 18F-FDG-PET/CT scan at 4 weeks for the detection of immune-related adverse events (rAE) in a cohort of patients with metastatic melanoma (mM) patients receiving immune-checkpoint inhibitors (ICI). PATIENTS AND METHODS: In this prospective non-interventional, one-centre clinical study, patients with mM, receiving ICI treatment, were regularly followed by 18F-FDG PET/CT. Patients were scanned at baseline, early point at week four (W4), week sixteen (W16) and week thirty-two (W32) after ICI initiation. A convolutional neural network (CNN) was used to segment three organs: lung, bowel, thyroid. QIB of irAE - SUVX% - was analyzed within the target organs and correlated with the clinical irAE status. Area under the receiver-operating characteristic curve (AUROC) was used to quantify irAE detection performance. RESULTS: A total of 242 18F-FDG PET/CT images of 71 mM patients were prospectively collected and analysed. The early W4 scan showed improved detection only for the thyroid gland compared to W32 scan (p=0.047). The AUROC for detection of irAE in the three target organs was highest when SUVX% was extracted from W16 scan and was 0.76 for lung, 0.53 for bowel and 0.81 for thyroid. SUVX% extracted from W4 scan did not improve detection of irAE compared to W16 scan (lung: p = 0.54, bowel: p = 0.75, thyroid: p = 0.3, DeLong test), as well as compared to W32 scan in lungs (p = 0.32) and bowel (p = 0.3). CONCLUSIONS: Early time point 18F-FDG PET/CT at W4 did not lead to statistically significant earlier detection of irAE. However, organ 18F-FDG uptake as quantified by SUVX% proved to be a consistent QIB of irAE. To better assess the role of 18F-FDG PET/CT in irAE detection, the time evolution of 18F-FDG PET/CT quantifiable inflammation would be of essence, only achievable in multi centric studies.

Individual-specific metabolic network based on 18F-FDG PET revealing multi-level aberrant metabolisms in Parkinson's disease.

Metabolic network analysis in Parkinson's disease (PD) based on 18F-FDG PET has revealed PD-related metabolic patterns. However, alterations at the systemic metabolic network level and at the connection level between different brain regions still remain unknown. This study aimed to explore metabolic network alterations at multiple network levels among PD patients using an individual-specific metabolic network (ISMN) approach. 18F-FDG-PET images of patients with PD (n = 34) and healthy subjects (n = 47) were collected. Healthy subjects were further separated into reference group (n = 28) and control group (n = 19) randomly. Standardized uptake value normalized by lean body mass ratio (SULr) maps was calculated from the PET images. ISMNs were constructed based on SULr maps for PD patients and controls with reference to the reference group. Comparisons of nodal and edge features were performed between PD and control groups. Correlation analysis was conducted between multilevel network properties and clinical scales in PD group. A linear classifier was trained based on nodal or edge features to distinguish PD from controls. The distance from each patient's ISMN to the group-level difference network showed a negative correlation with Hoehn and Yahr stage (r = -0.390, p = .023). Eight nodes from ISMN were identified which exhibited significantly increased nodal degree in PD patients compared to controls (p < .05). Eleven edges were observed which demonstrated significant distinctions in Z-score values in comparisons to the control group (p < .05). Furthermore, the nodal and edge features showed comparable performances in PD diagnosis compared to the traditional SULr values, with area under the receiver operating characteristic curve larger than 0.91. The proposed ISMN approach revealed systemic metabolic deviations, as well as nodal and edge distinctions in PD, which might be supplementary to the existing findings on PD-related metabolic patterns.

Combination of circulating tumor cells and 18F-FDG PET/CT for precision diagnosis in patients with non-small cell lung cancer.

PURPOSE: To investigate the value of 2-deoxy-18f-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) and circulating tumor cells (CTCs) for the differential diagnosis of patients with benign lung diseases and those with NSCLC. To explore the phenotypic heterogeneity of CTCs and their correlation with FDG uptake in patients with Stage I-IV NSCLC. METHODS: Blood specimens from patients with benign lung diseases and patients with primary NSCLC were collected for the detection of CTCs and their subtypes (epithelial, mixed, and mesenchymal) and analyzed for 18F-FDG PET/CT tumor metabolic parameters, including the maximum standardized uptake value (SUVmax), standard uptake value (SUL), metabolic tumor volume of primary lesion (MTV), total lesion glycolysis of primary lesion (TLG). Clinical data including age, gender, smoking history, tumor size, TNM stage and pathology type were also collected. The value of the two method alone and in combination for the differential diagnosis of benign and malignant was comparatively analyzed. Finally, the differences in CTC and its subtypes in different stages of NSCLC were compared, and FDG metabolic parameters were correlated with CTC subtypes. RESULTS: There were a total of 65 patients with pulmonary diseases, including 12 patients with benign pulmonary diseases and 53 patients with NSCLC. The mean age was 67 ± 10 (38-89 years), 27 were females and 38 were males. 31 (22 males and 9 females) had a long history of smoking. The mean size of the largest diameter of all single lesions was 36 ± 22 mm with a range of 10-108 mm. Seven out of 12 benign diseases were inflammatory granulomatous lesions and 5 were inflammatory pseudotumours. Twenty-four out of 53 NSCLC were adenocarcinomas and 29 were squamous carcinomas. Twelve out of 53 patients with NSCLC were in Stage I, 10 were in Stage II, 17 were in Stage III and 14 were in Stage IV. SUVmax, SUL, MTV, TLG, total CTCs, epithelial CTCs, and mixed CTCs were all valuable in the differential diagnosis of benign and malignant. TLG combined with mixed CTCs was statistically different from all other diagnostic methods (p < 0.05) and higher than any other diagnostic criteria. In the differential diagnosis of benign and Stage I NSCLC, only total CTC (Z = -2.188 p = 0.039) and mixed CTCs (Z = -3.020 p = 0.014) had certain diagnostic efficacy, and there was no statistical difference between them (p = 0.480). Only mesenchymal CTCs differed in Stage I-IV NSCLC, with a higher number of those who developed distant metastases than those who had non-distant metastases. Epithelial CTCs correlated with SUVmax (r = 0.333, p = 0.015) and SUL (r = 0.374, p = 0.006). Mmesenchymal CTCs correlated with MTV (r = 0.342, p = 0.018) and TLG (r = 0.319, p = 0.02). Further subgroup analyses revealed epithelial CTCs were correlated with SUVmax (r = 0.543, p = 0.009) and SUL (r = 0.552, p = 0.008), and the total CTCs was correlated with SUVmax (r = 0.622, p = 0.003), SUL (r = 0.652, p = 0.003), MTV (r = 0.460, p = 0.031), and TLG (r = 0.472, p = 0.027) in the early group (Stage I-II). Only mesenchymal CTCs was associated with MTV (r = 0.369, p = 0.041), and TLG (r = 0.415, p = 0.02) in the intermediate-late group (Stage III-IV). CONCLUSION: Both FDG PET metabolic parameters and CTCs demonstrated diagnostic value for NSCLC, and combining TLG with mixed CTCs could enhance their diagnostic efficacy. The total CTCs and mixed CTCs showed greater diagnostic value than FDG PET in distinguishing benign lesions from Stage I NSCLC. In NSCLC patients, the epithelial CTCs exhibited a positive correlation with SUVmax and SUL, while mesenchymal CTCs correlated with MTV, and TLG. Besides, epithelial CTCs showed stronger correlations with SUVmax and SUL, and total CTCs showed stronger correlations with SUVmax, SUL, MTV, and TLG in Stage I-II NSCLC. Only mesenchymal CTCs in Stage III-IV NSCLC showed correlations with MTV and TLG. Stage IV NSCLC cases displayed a higher number of mesenchymal CTCs.

Impact of multidisciplinary Endocarditis Team on management of infective endocarditis.

Infective Endocarditis (IE) is a complex, life-threatening disease. The aim of the present study was to evaluate the impact of the Endocarditis-Team on management of IE. This observational study conducted at a university hospital (2015‒22), included adult patients with IE. The study period was divided in two periods: before (pre-Endocarditis-Team; pre-ET) and after the establishment of the Endocarditis-Team (post-Endocarditis-Team; post-ET) on January 2018. Among 505 IE episodes (187 in pre-Endocarditis-Team, 318 in post-ET period), 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography was more commonly used in post-ET period (14% vs. 28 %; p < 0.001). Overall, thirty-day and one-year mortality were 14 % and 27 %, respectively; no difference was observed between the two periods. In post-ET period, the administration of 4-weeks, rather than 6-weeks, of intravenous antimicrobial treatment was higher than in the post-ET period (15% vs. 45 %; p < 0.001). Indication for surgery was present in 115 (61 %) patients in pre-ET and in 153 (48 %) in the post-ET period. In post-ET period, among patients with indication, valve surgery was more frequently performed (66% vs. 78 %; p = 0.038). Such difference was due to a higher acceptance of operative indication by the cardiac surgeon (69% vs. 94 %; p = 0.013). The observed increase in number of patients benefiting from cardiac surgery in the post-ET period led to a decrease of subsequent embolic events, since among patients with operative indication (n = 268), new embolic events after the establishment of the indication were more common in the pre-ET period compared to post-ET (23% vs. 12 %; p = 0.033). After the implementation of the multidisciplinary Endocarditis-Team we observed several improvements in the general management of IE patients.

Deep learning-based image analysis predicts PD-L1 status from 18F-FDG PET/CT images in non-small-cell lung cancer.

Background: There is still a lack of clinically validated biomarkers to screen lung cancer patients suitable for programmed dead cell-1 (PD-1)/programmed dead cell receptor-1 (PD-L1) immunotherapy. Detection of PD-L1 expression is invasively operated, and some PD-L1-negative patients can also benefit from immunotherapy; thus, the joint modeling of both deep learning images and clinical features was used to improve the prediction performance of PD-L1 expression in non-small cell lung cancer (NSCLC). Methods: Retrospective collection of 101 patients diagnosed with pathology in our hospital who underwent 18F FDG PET/CT scans, with lung cancer tissue Tumor Propulsion Score (TPS) ≥1% as a positive expression. Lesions were extracted after preprocessing PET/CT images, and using deep learning 3D DenseNet121 to learn lesions in PET, CT, and PET/CT images, 1,024 fully connected features were extracted; clinical features (age, gender, smoking/no smoking history, lesion diameter, lesion volume, maximum standard uptake value of lesions [SUVmax], mean standard uptake value of lesions [SUVmean], total lesion glycolysis [TLG]) were combined for joint modeling based on the structured data Category Embedding Model. Results: Area under a receiver operating characteristic (ROC) curve (AUC) and accuracy of predicting PD-L1 positive for PET, CT, and PET/CT test groups were 0.814 ± 0.0152, 0.7212 ± 0.0861, and 0.90 ± 0.0605, 0.806 ± 0.023, 0.70 ± 0.074, and 0.950 ± 0.0250, respectively. After joint clinical feature modeling, the AUC and accuracy of predicting PD-L1 positive for PET/CT were 0.96 ± 0.00905 and 0.950 ± 0.0250, respectively. Conclusion: This study combines the features of 18F-FDG PET/CT images with clinical features using deep learning to predict the expression of PD-L1 in NSCLC, suggesting that 18F-FDG PET/CT images can be conducted as biomarkers for PD-L1 expression.

Comparison of 18F-FDG PET/CT and 18F-FAPI PET/CT in Systemic Staging of Newly Diagnosed Breast Cancer.

RATIONALE AND OBJECTIVES: The purpose of this study was to compare the performance of 18F-FAPI PET/CT and 18F-FDG PET/CT in systemic staging of newly diagnosed breast cancer. METHODS: Breast cancer patients with initial clinical stage IIB-IIIC who have consequently underwent both 18F-FAPI and 18F-FDG PET/CT from June 2022 to June 2023 were retrospectively analyzed. New clinical stage was assigned to each patient if unsuspected level III axillary and extraaxillary regional lymph node metastases (URNM) and/or distant metastases were disclosed after PET/CT. Sensitivity for both tests was calculated on patient basis and lesion basis using histology or follow-up imaging as reference standard. RESULTS: 38 patients were included. The overall upstaging rate was 47.4% for 18F-FAPI PET/CT (18/38) and 34.2% for 18F-FDG PET/CT (13/38). The rate of distant metastases disclosed by 18F-FAPI PET/CT was 5.5% in stage IIB patients, 30% in stage IIIA patients, 50% in stage IIIB patients, and 75% in stage IIIC patients. On patent-based analysis, the sensitivity of 18F-FAPI PET/CT was significantly different from that of 18F-FDG PET/CT in detecting URNM [100% (13/13) vs 53.8% (7/13), (P = 0.031)], but not for distant metastases [100% (10/10) vs 90% (9/10), (P = 1.000)]. On lesion-based analysis, the sensitivity of 18F-FAPI PET/CT was significantly higher than that of 18F-FDG PET/CT in detecting URNM [97.6% (41/42) vs 52.4% (22/42), (P < 0.001)] and distant metastases [98.1% (51/52) vs 67.3% (35/52), (P < 0.001)]. CONCLUSION: 18F-FAPI PET/CT leads to significant upstaging in newly diagnosed breast cancer, in a rate higher than 18F-FDG PET/CT. The significantly higher lesion-based sensitivity in unsuspected metastases implies a future role of 18F-FAPI PET/CT in evaluation of metastatic disease burden.

Adrenal ganglioneuroma with nodal metastases on 123I-MIBG SPECT/CT and 18F-FDG PET/CT.

Ganglioneuroma is a well-differentiated tumor originating from neural crest cells of the sympathetic nervous system. Although benign, a few cases have been reported that ganglioneuroma can metastasize to other sites. We report a case of adrenal ganglioneuroma with para-aortic nodal metastases with low FDG and MIBG uptake. In order to avoid unnecessary wide excision or aggressive medication, it is important to consider the possibility of ganglioneuroma preoperatively even if with metastases.

Comparing the diagnostic efficacy of [18F]FDG PET/CT and MRI in the initial diagnosis of ovarian cancer: a meta-analysis.

PURPOSE: This meta-analysis was conducted to assess the relative diagnostic effectiveness of [18F]FDG PET/CT and MRI in the initial detection of ovarian cancer. METHODS: A thorough literature search was conducted using PubMed, Embase, and Web of Science databases to locate relevant studies published up to April 2024. The selected studies were those that evaluated diagnostic performance of [18F]FDG PET/CT and MRI for the initial detection of ovarian cancer. Sensitivity and specificity metrics were analyzed employing the DerSimonian and Laird random-effects model, with further transformation utilizing the Freeman-Tukey double arcsine method. The quality of included studies was appraised using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. RESULTS: The meta-analysis included 23 articles encompassing a total of 1973 patients. The sensitivity of [18F]FDG PET/CT was found to be higher than that of MRI (0.94 vs. 0.87, P = 0.02). In terms of specificity, [18F]FDG PET/CT and MRI demonstrated similar values (0.87 vs. 0.86, P = 0.90). An assessment of publication bias using the funnel plot asymmetry test revealed no significant bias for any outcomes (Egger's test: all P > 0.05). CONCLUSIONS: Our meta-analysis reveals that [18F]FDG PET/CT exhibits higher sensitivity while maintaining similar specificity compared to MRI for the initial detection of ovarian cancer. However, the substantial heterogeneity observed across studies may influence these findings. Consequently, larger-scale prospective studies are necessary to validate these results.

Impact of different parametric Patlak imaging approaches and comparison with a 2-tissue compartment pharmacokinetic model with a long axial field-of-view (LAFOV) PET/CT in oncological patients.

AIM: The recently introduced Long-Axial-Field-of-View (LAFOV) PET-CT scanners allow for the first-time whole-body dynamic- and parametric imaging. Primary aim of this study was the comparison of direct and indirect Patlak imaging as well as the comparison of different time frames for Patlak calculation with the LAFOV PET-CT in oncological patients. Secondary aims of the study were lesion detectability and comparison of Patlak analysis with a two-tissue-compartment model (2TCM). METHODOLOGY: 50 oncological patients with 346 tumor lesions were enrolled in the study. All patients underwent [18F]FDG PET/CT (skull to upper thigh). Here, the Image-Derived-Input-Function) (IDIF) from the descending aorta was used as the exclusive input function. Four sets of images have been reviewed visually and evaluated quantitatively using the target-to-background (TBR) and contrast-to-noise ratio (CNR): short-time (30 min)-direct (STD) Patlak Ki, short-time (30 min)-indirect (STI) Patlak Ki, long-time (59.25 min)-indirect (LTI) Patlak Ki, and 50-60 min SUV (sumSUV). VOI-based 2TCM was used for the evaluation of tumor lesions and normal tissues and compared with the results of Patlak model. RESULTS: No significant differences were observed between the four approaches regarding the number of tumor lesions. However, we found three discordant results: a true positive liver lesion in all Patlak Ki images, a false positive liver lesion delineated only in LTI Ki which was a hemangioma according to MRI and a true negative example in a patient with an atelectasis next to a lung tumor. STD, STI and LTI Ki images had superior TBR in comparison with sumSUV images (2.9-, 3.3- and 4.3-fold higher respectively). TBR of LTI Ki were significantly higher than STD Ki. VOI-based k3 showed a 21-fold higher TBR than sumSUV. Parameters of different models vary in their differential capability between tumor lesions and normal tissue like Patlak Ki which was better in normal lung and 2TCM k3 which was better in normal liver. 2TCM Ki revealed the highest correlation (r = 0.95) with the LTI Patlak Ki in tumor lesions group and demonstrated the highest correlation with the STD Patlak Ki in all tissues group and normal tissues group (r = 0.93 and r = 0.74 respectively). CONCLUSIONS: Dynamic [18F]-FDG with the new LAFOV PET/CT scanner produces Patlak Ki images with better lesion contrast than SUV images, but does not increase the lesion detection rate. The time window used for Patlak imaging plays a more important role than the direct or indirect method. A combination of different models, like Patlak and 2TCM may be helpful in parametric imaging to obtain the best TBR in the whole body in future.

Evaluating the Utility of 18F-FDG PET/CT in Cancer of Unknown Primary.

Cancer of unknown primary (CUP) represents a heterogeneous group of metastatic tumors for which standardized diagnostic work-up fails to identify the primary site. We aimed to describe the Peter MacCallum Cancer Centre experience with 18F-FDG PET/CT in extracervical CUP with respect to detection of a primary site and its impact on management. A secondary aim was to compare overall survival (OS) in patients with and without a detected primary site. Methods: CUP patients treated between 2014 and 2020 were identified from medical oncology clinics and 18F-FDG PET/CT records. Information collated from electronic medical records included the suspected primary site and treatment details before and after 18F-FDG PET/CT. Clinicopathologic details and genomic analysis were used to determine the clinically suspected primary site and compared against 2 independent masked reads of 18F-FDG PET/CT images by nuclear medicine specialists to determine sensitivity, specificity, accuracy, and the rate of detection of the primary site. Results: We identified 147 patients, 65% of whom had undergone molecular profiling. The median age at diagnosis was 61 y (range, 20-84 y), and the median follow-up time was 74 mo (range, 26-83 mo). Eighty-two percent were classified as having an unfavorable CUP subtype as per international guidelines.18F-FDG PET/CT demonstrated a primary site detection rate of 41%, resulted in a change in management in 22%, and identified previously occult disease sites in 37%. Median OS was 16.8 mo for all patients and 104.7 and 12.1 mo for favorable and unfavorable CUP subtypes, respectively (P < 0.0001). Median OS in CUP patients when using 18F-FDG PET/CT, clinicopathologic, and genomic information was 19.8 and 8.5 mo when a primary site was detected and not detected, respectively (P = 0.016). Multivariable analysis of survival adjusted for age and sex remained significant for identification of a potential primary site (P < 0.001), a favorable CUP (P < 0.001), and an Eastern Cooperative Oncology Group status of 1 or less (P < 0.001). Conclusion: 18F-FDG PET/CT plays a complementary role in CUP diagnostic work-up and was able to determine the likely primary site in 41% of cases. OS is improved with primary site identification, demonstrating the value of access to diagnostic 18F-FDG PET/CT for CUP patients.