Pulmonary enteric adenocarcinoma (PEAC) is an extremely rare variant of lung adenocarcinoma characterized by pathological features similar to those of colorectal adenocarcinoma. It is mostly observed on computed tomography (CT) and positron emission tomography (PET)/CT as solitary or multiple nodules/masses in the lung. It tends to grow rapidly and is difficult to distinguish from lung metastatic colorectal cancer. Herein, we have presented a case of PEAC with special imaging findings.
A chest CT scan of a 72-year-old man with suspected chronic pneumonia revealed a well-defined consolidation in the upper lobe of the left lung. The lesion was slightly enlarged at the 9-month follow-up, and low FDG accumulation was subsequently observed using 18F-fluorodeoxyglucose (18F-FDG) PET/CT scans. The patient was later diagnosed with PEAC through percutaneous lung biopsy.
Our case has demonstrated specific imaging findings of PEAC.

UNASSIGNED: The purpose of this study was to compare the diagnostic efficacy of PET/CT-aided CT-guided and routine CT-guided transthoracic needle biopsy for lung lesions.
UNASSIGNED: A total of 458 patients with suspicious lung lesions were referred for CT-guided biopsy, with 227 patients assigned to the PET/CT group and 231 patients assigned to the CT group. The clinical characteristics and diagnostic yield were compared between the two groups. Furthermore, conducting subgroup analysis to evaluate the differences of diagnostic success or failure between the two groups.
UNASSIGNED: The sensitivity and diagnostic accuracy rate differed significantly (P = 0.035, P = 0.048). In the PET/CT group, the values were 95.7% and 96.3%, respectively, while in the CT group, they were 90.1% and 91.9%. When considering non-diagnostic cases, the overall diagnostic success rate increased markedly in PET/CT group (93.0% vs. 83.1%, P = 0.001). In our subgroup analysis, the PET/CT group demonstrated superiority in detecting lesions larger than 3 cm (OR, 4.81; 95CI%, 2.03 - 11.36), while showing a moderate effect in lesions smaller than 3 cm (OR, 1.09; 95CI%, 0.42 - 2.81). Significant effect modification was observed in large lesions in the PET/CT group (P for interaction = 0.023).
UNASSIGNED: 18F-FDG-PET/CT enhances the diagnostic efficacy of CT-guided transthoracic needle biopsy for lung lesions, and the incremental value can be modified by lesion size, particularly when the diameter is larger than 3 cm.

OBJECTIVE: To investigate the value of 18F-FDG PET/CT in diagnosis and disease evaluation of Langerhans cell histiocytosis (LCH).
METHODS: A retrospective analysis of 31 patients with LCH confirmed by histopathology was performed. A systematic analysis of the PET/CT imaging manifestations of LCH was performed, recording patients who were treated and receiving PET/CT for efficacy evaluation. In addition, clinical and laboratory data of LCH patients were collected, and the correlation between these data and PET/CT metabolic parameters was initially investigated.
RESULTS: Of the 31 patients, thirty had at least 1 PET/CT positive lesions (96.7%), and one had only skin damage without abnormalities on PET/CT. Of 31 patients, fifteen (48.4%) had single system (SS) disease (9 cases with a single site and 6 cases with multiple sites) and 16 (51.6%) had multisystem (MS) disease (6 low risk and 10 high risk cases). The incidence of LCH lesions in the bone, lymphatic system, pituitary gland, liver, soft tissue, thyroid gland, thymus, and lungs was 20 cases (64.5%), 12 cases (38.7%), 3 cases (9.7%), 2 cases (6.5%), 2 cases (6.5%), 1 case (3.2%), 1 case (3.2%), and 8 cases (25.8%), respectively. A total of 21 PET/CT follow-up scanning were performed in 13 patients receiving chemotherapy, with 13 (61.9%) partial metabolic remission (PMR), 6 (28.6%) progressive metabolic disease (PMD), and 2 (9.5%) stable metabolic disease (SMD), according to PET Response Evaluation Criteria in Solid Tumors (PRECIST) 1.0. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and Lactic Dehydrogenase (LDH) were positively correlated with TTLG (total TLG) (R2 = 0.3256, 0.2409, 0.4205, P < 0.05). The Re-examine SUVmax is positively correlated with re-examine LDH (R2 = 0.7285, P < 0.05).
CONCLUSIONS: 18F-FDG PET/CT is an effective way to diagnose and evaluate LCH. PET metabolic parameters were associated with laboratory inflammatory markers, suggesting that 18F-FDG PET/CT may be helpful in evaluating disease activity of LCH.

OBJECTIVE: Commercialized total-body PET scanners can provide high-quality images due to its ultra-high sensitivity. We compared the dynamic, regular static, and delayed 18F-fluorodeoxyglucose (FDG) scans to detect lesions in oncologic patients on a total-body PET/CT scanner.
METHODS: In all, 45 patients were scanned continuously for the first 60 min, followed by a delayed acquisition. FDG metabolic rate was calculated from dynamic data using full compartmental modeling, whereas regular static and delayed SUV images were obtained approximately 60- and 145-min post-injection, respectively. The retention index was computed from static and delayed measures for all lesions. Pearson\'s correlation and Kruskal-Wallis tests were used to compare parameters.
RESULTS: The number of lesions was largely identical between the three protocols, except MRFDG and delayed images on total-body PET only detected 4 and 2 more lesions, respectively (85 total). FDG metabolic rate (MRFDG) image-derived contrast-to-noise ratio and target-to-background ratio were significantly higher than those from static standardized uptake value (SUV) images (P < 0.01), but this is not the case for the delayed images (P > 0.05). Dynamic protocol did not significantly differentiate between benign and malignant lesions just like regular SUV, delayed SUV, and retention index.
CONCLUSIONS: The potential quantitative advantages of dynamic imaging may not improve lesion detection and differential diagnosis significantly on a total-body PET/CT scanner. The same conclusion applied to delayed imaging. This suggested the added benefits of complex imaging protocols must be weighed against the complex implementation in the future.
CONCLUSIONS: Total-body PET/CT was known to significantly improve the PET image quality due to its ultra-high sensitivity. However, whether the dynamic and delay imaging on total-body scanner could show additional clinical benefits is largely unknown. Head-to-head comparison between two protocols is relevant to oncological management.

The impact of estrogen on brain function, especially in individuals with diabetes, remains uncertain. This study aims to compare cerebral glucose metabolism levels in intact rats, ovariectomized (OVX) rats, and 17β-estradiol (E2)-treated OVX diabetic female rats. Sixteen rats were administered a single intraperitoneal injection of 70 mg/kg streptozotocin (STZ) to induce diabetes (intact, n = 6; OVX, n = 6; OVX+E2-treated, n = 4). Additionally, 18 rats received an equivalent solvent dose via intraperitoneal injection (intact, n = 6; OVX, n = 6; OVX+E2-treated, n = 6). After 4 weeks of STZ or solvent administration, positron emission tomography scans with 18F-fluorodeoxyglucose (18F-FDG) injection were employed to assess cerebral glucose metabolism. The diabetic rats exhibited substantial reductions in 18F-FDG uptake across all brain regions (all P < 0.01), in contrast to the control rats. Moreover, intact and OVX + E2-treated diabetic female rats displayed more pronounced decreases in cerebral glucose metabolism in the amygdala and hippocampus compared to OVX diabetic female rats (P < 0.05). These findings suggest that diabetes creates an environment wherein estrogen exacerbates neuropathology and intensifies neuronal activity.

UNASSIGNED: To explore the clinical role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in differentiating malignant pleural effusion (MPE) from benign pleural effusion (BPE) in patients with lung cancer.
UNASSIGNED: Over a 8-year period, we retrospectively reviewed PET/CT data of lung cancer patients with pleural effusion, with 237 participants enrolled for analysis. The nature of pleural effusion was confirmed using pleural cytology or biopsy. MPE versus BPE comparison and multiple regression analysis were performed. Receiver operating characteristic (ROC) curve analysis was used for evaluating the diagnostic performance.
UNASSIGNED: Of the 237 participants, 170 had MPEs and 67 had BPEs. Compared with BPEs, MPEs had higher pleural SUVmax and thicker pleura and were more common among non-small cell lung cancers, peripheral tumors, and women (p < 0.05). BPEs had larger and higher 18F-FDG uptake thoracic lymph nodes and more complications of pneumonia (p < 0.05) than MPEs. Multiple regression analysis was used to identify the pleural SUVmax (odds ratio, OR = 38.8), sex (OR = 0.033), and mediastinal lymphoid node size (OR = 0.86) as independent risk factors for MPEs. The sensitivity, specificity, and area under the ROC curve (AUC) in the combined ROC curve analysis by using the three factors were 95.3%, 95.5%, and 0.989, respectively.
UNASSIGNED: 18F-FDG PET/CT integrated imaging is an effective non-invasive method for differential diagnosis of MPE in patients with lung cancer. Pleural SUVmax combined with thoracic lymph nodes and sex has high diagnostic value.

BACKGROUND: An ectopic meningioma, such as a primary pulmonary meningioma (PPM), is a rare type of tumor that primarily originates outside of the central nervous system. The most common presentation of PPM is isolated pulmonary nodules or masses, and most of them are benign. Only sporadic cases have been reported. This case reported a giant primary pulmonary meningioma and systematically reviewed previously reported cases in the literature.
METHODS: A 55-year-old female suffered from asthma after activity, chest tightness, and a persistent dry cough for 2 months. Chest computed tomography (CT) showed a huge mass with calcification in the left lower lobe. And positron emission tomography (PET)/CT revealed mild FDG accumulation of the mass. The mass was finally surgically removed and PPM was confirmed according to histopathologic examinations.
CONCLUSIONS: PPM is a rare disease with heterogeneity not only in CT features but also in glucose metabolism. FDG uptake levels do not identify benign from malignant, benign PPM may have high FDG uptake and malignant may have low.

Erdheim-Chester disease (ECD) is an uncommon non-Langerhan cell histiocytosis that affects multiple systems and most commonly involves the bones. A 34-year-old patient with a three-month history of progressive dysphagia, underwent the gastroscopy which revealed esophageal mucosal constriction 34 cm from the incisor and external pressure stenosis. Enhanced computed tomography (CT), magnetic resonance imaging (MRI), and 2-[fluorine-18] fluoro-2-deoxy-d-glucose (18F-FDG) positron emission tomography (PET)/CT findings confirmed diffuse soft-tissue infiltration filled periesophageal space and excluded lesions involving the bone and other organs within the scanning range. The patient was later diagnosed with esophageal involvement of ECD by thoracotomy surgery and paraesophageal soft tissue biopsy. Progressive dysphagia, a rare clinical manifestation of ECD, has been reported in only two cases. It is the first demonstration of MRI and PET/CT imaging findings of ECD esophageal invasion as far as we known. Through the comparison of multiple images, we have a preliminary recognition of characteristic radiological features of gastrointestinal infiltration in ECD.

UNASSIGNED: This study aimed to investigate the feasibility of predicting progression-free survival (PFS) in breast cancer patients using pretreatment 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) radiomics signature and clinical parameters.
UNASSIGNED: Breast cancer patients who underwent 18F-FDG PET/CT imaging before treatment from January 2012 to December 2020 were eligible for study inclusion. Eighty-seven patients were randomly divided into training (n = 61) and internal test sets (n = 26) and an additional 25 patients were used as the external validation set. Clinical parameters, including age, tumor size, molecular subtype, clinical TNM stage, and laboratory findings were collected. Radiomics features were extracted from preoperative PET/CT images. Least absolute shrinkage and selection operators were applied to shrink feature size and build a predictive radiomics signature. Univariate and multivariate Cox proportional hazards models and Kaplan-Meier analysis were used to assess the association of rad-score and clinical parameter with PFS. Nomograms were constructed to visualize survival prediction. C-index and calibration curve were used to evaluate nomogram performance.
UNASSIGNED: Eleven radiomics features were selected to generate rad-score. The clinical model comprised three parameters: clinical M stage, CA125, and pathological N stage. Rad-score and clinical-model were significantly associated with PFS in the training set (P< 0.01) but not the test set. The integrated clinical-radiomics (ICR) model was significantly associated with PFS in both the training and test sets (P< 0.01). The ICR model nomogram had a significantly higher C-index than the clinical model and rad-score in the training and test sets. The C-index of the ICR model in the external validation set was 0.754 (95% confidence interval, 0.726-0.812). PFS significantly differed between the low- and high-risk groups stratified by the nomogram (P = 0.009). The calibration curve indicated the ICR model provided the greatest clinical benefit.
UNASSIGNED: The ICR model, which combined clinical parameters and preoperative 18F-FDG PET/CT imaging, was able to independently predict PFS in breast cancer patients and was superior to the clinical model alone and rad-score alone.

While early-onset Parkinson\'s disease (EOPD) caused by mutations in the parkin gene (PRKN) tends to have a relatively benign course compared to genetically undetermined (GU)-EOPD, the exact underlying mechanisms remain elusive. We aimed to search for the differences between PRKN-EOPD and GU-EOPD by dopamine transporter (DAT) and glucose metabolism positron-emission-tomography (PET) imaging. Twelve patients with PRKN-EOPD and 16 with GU-EOPD who accepted both 11C-2b-carbomethoxy-3b-(4-trimethylstannylphenyl) tropane (11C-CFT) and 18F-fluorodeoxyglucose PET were enrolled. The 11C-CFT uptake was analyzed on both regional and voxel levels, whereas glucose metabolism was assessed in a voxel-wise fashion. Correlations between DAT and glucose metabolism imaging, DAT imaging and clinical severity, as well as glucose metabolism imaging and clinical severity were explored. Both clinical symptoms and DAT-binding patterns in the posterior putamen were highly symmetrical in patients with PRKN-EOPD, and dopaminergic dysfunction in the ipsilateral putamen was severer in patients with PRKN-EOPD than GU-EOPD. Meanwhile, the DAT binding was associated with the severity of motor dysfunction in  patients with GU-EOPD only. Patients with PRKN-EOPD showed increased glucose metabolism in the contralateral medial frontal gyrus (supplementary motor area (SMA)), contralateral substantia nigra, contralateral thalamus, and contralateral cerebellum. Notably, glucose metabolic activity in the contralateral medial frontal gyrus was inversely associated with regional DAT binding in the bilateral putamen. Patients with PRKN-EOPD showed enhanced metabolic connectivity within the bilateral putamen, ipsilateral paracentral and precentral lobules, and the ipsilateral SMA. Collectively, compared to GU-EOPD, PRKN-EOPD is characterized by symmetrical, more severe dopaminergic dysfunction and relative increased glucose metabolism. Meanwhile, SMA with elevated glucose metabolism and enhanced connectivity may act as compensatory mechanisms in PRKN-EOPD.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s43657-022-00077-8.