Fluorine-18 Fluorodeoxyglucose Uptake Research Articles

Clinical and imaging features of pulmonary mixed squamous cell and glandular papilloma: a case report and literature review

Pulmonary mixed squamous cell and glandular papilloma (MSGP) is a rare benign lung tumor with both squamous and glandular epithelial components. Reports on primary lung MSGP are few, and the aim of this study is to describe the imaging, including computed tomography (CT) and positron emission tomography (PET) findings, and histopathological characteristics of a case of MSGP in our hospital. A 53-year-old woman with no smoking history who underwent a chest CT scan revealed a nodule in the upper lobe of the left lung. The solid nodule showed no lobulation or spiculation but demonstrated significant enhancement on contrast-enhanced CT and increased fluorine-18 fluorodeoxyglucose (18F-FDG) uptake on PET. Moreover, a literature review identified 19 cases of lung MSGPs involving imaging findings, including CT and/or PET imaging. Except for one patient with a ground glass nodule, the rest were solid and ranged in size from 0.7 to 8.2 cm, which can present as a mildly to significantly increased 18F-FDG uptake on PET. MSGP is a rare benign tumor entity, and understanding its imaging findings and pathological immunohistochemical characteristics will help to improve the accurate diagnosis of MSGP so as to avoid unnecessary lobectomy and mediastinal lymph node dissection.

Fluorine-18 fluorodeoxyglucose uptake change in liver, mediastinal blood pool, and lymphoid cell-rich organs during programmed cell death-1 immunotherapy in lymphoma.

The aim of this study was to evaluate metabolism change in reference organs (liver and mediastinum) and lymphoid cell-rich organs (spleen and bone marrow) during programmed cell death-1 immunotherapy in relapsed or refractory lymphoma patients. A total of 66 patients with baseline and serial monitoring fluorodeoxyglucose (FDG) PET/computed tomography scans were retrospectively enrolled. Mean standardized uptake value (SUV) and maximum SUV of evaluated organs were obtained by two reviewers, and their association with tumor burden and clinical response were evaluated. Immune-related adverse events detected by FDG PET/computed tomography were also recorded. The SUV values of reference organs and lymphoid cell-rich organs did not change significantly during the immunotherapy process. The intersubject variability of these values ranged from 13.0 to 28.5%. Meanwhile, metabolism of reference organs was affected by neither the tumor burden nor clinical response. SUV change of lymphoid cell-rich organs was associated with clinical response to immunotherapy. Responders showed decreased metabolism, while nonresponders showed a reverse trend (spleen SUVmaximum: -0.30 ± 0.47 vs. 0.18 ± 0.39, P = 0.001, spleen SUVmean: -0.24 ± 0.39 vs. 0.14 ± 0.31, P = 0.001; and bone marrow SUVmaximum: -0.14 ± 0.37 vs. 0.07 ± 0.46, P = 0.042, respectively). The influence of immune-related adverse events on the SUV change in evaluated organs was NS. During programmed cell death-1 immunotherapy, metabolism change of reference organs is influenced neither by tumor burden nor by clinical response, while FDG uptake change of lymphoid cell-rich organs is significantly associated with clinical response.

Semiquantitative 18F-FDG PET/CT in monitoring glucocorticoid response of immunoglobulin G4-related effusive constrictive pericarditis: a case report

BackgroundImmunoglobulin G4 (IgG4)-related effusive constrictive pericarditis (ECP) is a rare manifestation of IgG4-related disease (IgG4-RD). It can lead to persistent pericardial fibrosis, resulting in cardiac tamponade, diastolic dysfunction, and heart failure. Glucocorticoids are the primary treatment for effectively reducing inflammation and preventing fibrosis. However, guidelines for monitoring treatment response are lacking and tapering glucocorticoid therapy for specific target organs remains a challenge. Recent studies on IgG4-RD have demonstrated that semiquantitative measurements of fluorine-18 fluorodeoxyglucose (18F-FDG) uptake in the main involved organs in positron emission tomography/computed tomography (PET/CT) scanning are correlated to disease activity. We present a case of IgG4-related ECP to demonstrate the usefulness of 18F-FDG PET/CT for diagnosing and treatment follow-up of IgG4-related ECP.Case presentationHerein, a 66-year-old woman diagnosed with IgG4-related ECP presented with breathlessness, leg swelling, rales, and fever. Laboratory tests revealed markedly elevated levels of C-reactive protein, and transthoracic echocardiography revealed constrictive physiology with effusion. High IgG4 levels suggested an immune-related pathogenesis, while viral and malignant causes were excluded. Subsequent pericardial biopsy revealed lymphocyte and plasma cell infiltration in the pericardium, confirming the diagnosis of IgG4-related ECP. 18F-FDG PET/CT revealed increased uptake of 18F-FDG in the pericardium, indicating isolated cardiac involvement of IgG4-RD. Treatment with prednisolone and colchicine led to a rapid improvement in the patient’s condition within a few weeks. Follow-up imaging with 18F-FDG PET/CT after 3 months revealed reduced inflammation and improved constrictive physiology on echocardiography, leading to successful tapering of the prednisolone dose and discontinuation of colchicine.ConclusionThe rarity of IgG4-related ECP and possibility of multiorgan involvement in IgG4-RD necessitates a comprehensive diagnostic approach and personalized management. This case report highlights the usefulness of 18F-FDG PET/CT in the diagnosis and treatment follow-up of isolated pericardial involvement in IgG4-RD.

Evaluation of Lesions with Increased Fluorine-18 Fluorodeoxyglucose Uptake in the Stomach and Colon Incidental Detected by Positron Emission Tomography/Computed Tomography

Evaluation of Lesions with Increased Fluorine-18 Fluorodeoxyglucose Uptake in the Stomach and Colon Incidental Detected by Positron Emission Tomography/Computed Tomography

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome presenting as recurrent aseptic peritonitis in a patient receiving peritoneal dialysis: a case report

BackgroundVacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is caused by mutations in the ubiquitin-activating enzyme1 (UBA1) gene and characterised by an overlap between autoinflammatory and haematologic disorders.Case presentationWe reported a case of a 67-year-Japanese man receiving peritoneal dialysis (PD) who had recurrent aseptic peritonitis caused by the VEXAS syndrome. He presented with unexplained fevers, headache, abdominal pain, conjunctival hyperaemia, ocular pain, auricular pain, arthralgia, and inflammatory skin lesions. Laboratory investigations showed high serum C-reactive protein concentration and increased cell count in PD effluent. He was treated with antibiotics for PD-related peritonitis, but this was unsuccessful. Fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography images demonstrated intense FDG uptake in his left superficial temporal artery, nasal septum, and bilateral auricles. The working diagnosis was giant cell arteritis, and he was treated with oral prednisolone (PSL) 15 mg daily with good response. However, he was unable to taper the dose to less than 10 mg daily because his symptoms flared up. Since Tocilizumab was initiated, he could taper PSL dose to 2 mg daily. Sanger sequencing of his peripheral blood sample showed a mutation of the UBA1 gene (c.122 T > C; p.Met41Thr). We made a final diagnosis of VEXAS syndrome. He suffered from flare of VEXAS syndrome at PSL of 1 mg daily with his cloudy PD effluent. PSL dose of 11 mg daily relieved the symptom within a few days.ConclusionsIt is crucial to recognise aseptic peritonitis as one of the symptoms of VEXAS syndrome and pay attention to the systemic findings in the patients.

Prednisone vs methotrexate in treatment naïve cardiac sarcoidosis

BackgroundSide effects limit the long-term use of glucocorticoids in cardiac sarcoidosis (CS), and methotrexate has gained attention as steroid sparing agent although the supporting evidence is poor. This study compared prednisone monotherapy, methotrexate monotherapy or a combination of both, in the reduction of myocardial Fluorine-18 fluorodeoxyglucose (FDG) uptake and clinical stabilization of CS patients. Methods and resultsIn this retrospective cohort study, 61 newly diagnosed and treatment naïve CS patients commenced treatment with prednisone (N = 21), methotrexate (N = 30) or prednisone and methotrexate (N = 10) between January 2010 and December 2017. Primary outcome was metabolic response on FDG PET/CT and secondary outcomes were treatment patterns, major adverse cardiovascular events, left ventricular ejection fraction, biomarkers and side effects. At a median treatment duration of 6.2 [5.7-7.2] months, 71.4% of patients were FDG PET/CT responders, and the overall myocardial maximum standardized uptake value decreased from 6.9 [5.0-10.1] to 3.4 [2.1-4.7] (P < 0.001), with no significant differences between treatment groups. During 24 months of follow-up, 7 patients (33.3%; prednisone), 6 patients (20.0%; methotrexate) and 1 patient (10.0%; combination group) experienced at least one major adverse cardiovascular event (P = 0.292). Left ventricular ejection fraction was preserved in all treatment groups. ConclusionsSignificant suppression of cardiac FDG uptake occurred in CS patients after 6 months of prednisone, methotrexate or combination therapy. There were no significant differences in clinical outcomes during follow-up. These results warrant further investigation of methotrexate treatment in CS patients.

Physiologic 18F-FDG muscle uptake in severe COPD: Implications for accurate lung cancer staging.

Recognizing physiologic 18F-fluorodeoxyglucose (FDG) uptake in severe COPD is crucial to avoid mistaking it for lung cancer metastasis. Correlating 18F-FDG avid lesions with co-registered computed tomography is essential for accurate lung cancer staging and preventing unnecessary interventions.

Effect of Coronavirus Disease 2019 on Fluorine-18 fluorodeoxyglucose Uptake of Endocrine Organs

Objective: The new type of Coronavirus (SARS-CoV-2) damages cells by using the angiotensin converting enzyme-2 (ACE2) as a receptor to adhere and go through the cell membrane. It is known that some of the endocrine organs express ACE2 and these organs are potential targets for Coronavirus 2019 disease (Covid-19). This study aimed to investigate the effect of coronavirus disease 2019 (Covid-19) on Fluorine-18 fluorodeoxyglucose (18F-FDG) uptake of endocrine system organs.&#x0D; Methods: Sixteen patients who had Covid-19 underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) later, 77 patients who did not have Covid-19 underwent 18F-FDG PET/CT between March 2020-October 2021 were analyzed finally. SUVmax and SUVmean of the pituitary, thyroid, adrenal gland, pancreas, and testis measured from the PET/CT of the patients had Covid-19 were compared with SUVmax, and SUVmean measured from the same organs in PET/CT images of the patients who had not Covid-19.&#x0D; Results: Pancreatic mean SUVmax was significantly higher in patients who had Covid-19 than in patients who did not (p= 0.035). Pancreatic mean SUVmean was slightly higher in patients who had Covid-19 than in patients who did not, but this difference was not statistically significant (p= 0.072). No significant difference was found between the SUVmax and SUVmean values of the pituitary gland, thyroid gland, adrenal gland, and testis in patients who had Covid-19 and did not have.&#x0D; Conclusions: It was thought that the pancreas might have been affected in the course of Covid-19 due to the higher mean SUVmean values of the pancreas in patients who had Covid- 19.

Evaluation of Lesions with Increased Fluorine-18 Fluorodeoxyglucose Uptake in the Stomach and Colon Incidental Detected by Positron Emission Tomography/Computed Tomography

Evaluation of Lesions with Increased Fluorine-18 Fluorodeoxyglucose Uptake in the Stomach and Colon Incidental Detected by Positron Emission Tomography/Computed Tomography

Significance of incidental focal fluorine-18 fluorodeoxyglucose uptake in colon/rectum, thyroid, and prostate: With a brief literature review.

Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT), a functional imaging method, is usually performed on the entire torso, and regions of unexpected suspicious focal hypermetabolism are not infrequently observed. Among the regions, colon, thyroid, and prostate were found to be the common organs in a recent umbrella review. Some studies reported that a high rate of malignancy was shown in incidentally identified focal hypermetabolic regions and suggested that further examinations should not be ignored. To investigate the malignancy rate of incidental focal FDG uptake, useful PET parameters and their cutoffs in discrimination between malignant and benign lesions. Retrospectively, the final reports of 16510 F-18 FDG PET/CT scans performed at our hospital between January 2016 and March 2022 were reviewed to identify incidentally observed FDG uptake in the colon/rectum, thyroid, and prostate. The scans of patients with current or prior malignancies at each corresponding location, without the final reports of histopathology or colonoscopy (for colon and rectum) for the corresponding hypermetabolic regions, or with diffuse (not focal) hypermetabolism were excluded. Finally, 88 regions of focal colorectal hypermetabolism in 85 patients (48 men and 37 women with mean age 67.0 ± 13.4 years and 63.4 ± 15.8 years, respectively), 48 focal thyroid uptakes in 48 patients (12 men and 36 women with mean age 62.2 ± 13.1 years and 60.8 ± 12.4 years, respectively), and 39 focal prostate uptakes in 39 patients (mean age 71.8 ± 7.5 years) were eligible for this study. For those unexpected focal hypermetabolic regions, rates of malignancy were calculated, PET parameters, such as standardized uptake value (SUV), capable of distinguishing between malignant and benign lesions were investigated, and the cutoffs of those PET parameters were determined by plotting receiver operating characteristic curves. In the colon and rectum, 29.5% (26/88) were malignant and 33.0% (29/88) were premalignant lesions. Both SUVmax and SUVpeak differentiated malignant/premalignant from benign lesions, however, no parameters could distinguish malignant from premalignant lesions. Higher area under the curve was shown with SUVmax (0.752, 95%CI: 0.649-0.856, P < 0.001) and the cutoff was 7.6. In the thyroid, 60.4% (29/48) were malignant. The majority were well-differentiated thyroid cancers (89.7%, 26/29). The results of BRAF mutation tests were available for 20 of the 26 well-differentiated thyroid cancers and all 20 had the mutation. Solely SUVmax differentiated malignant from benign lesions and the cutoff was 6.9. In the prostate, 56.4% (22/39) were malignant. Only SUVmax differentiated malignant from benign lesions and the cutoff was 3.8. Overall, among the 175 focal hypermetabolic regions, 60.6% (106/175) were proven to be malignant and premalignant (in colon and rectum) lesions. Approximately 60% of the incidentally observed focal F-18 FDG uptake in the colon/rectum, thyroid, and prostate were found to be malignant. Of the several PET parameters, SUVmax was superior to others in distinguishing between malignant/premalignant and benign lesions. Based on these findings, incidental focal hypermetabolism should not be ignored and lead physicians to conduct further investigations with greater confidence.

The usefulness of the total metabolic tumor volume for predicting the postoperative recurrence of thoracic esophageal squamous cell carcinoma

BackgroundInduction or adjuvant therapies are not always beneficial for thoracic esophageal squamous cell carcinoma (ESCC) patients, and it is thus important to identify patients at high risk for postoperative ESCC recurrence. We investigated the usefulness of the total metabolic tumor volume (TMTV) for predicting the postoperative recurrence of thoracic ESCC.MethodsWe retrospectively analyzed the cases of 163 thoracic ESCC patients (135 men, 28 women; median age of 66 [range 34–82] years) treated at our hospital in 2007–2012. The TMTV was calculated from the fluorine-18 fluorodeoxyglucose (18F-FDG) uptake in the primary lesion and lymph node metastases. The optimal cut-off values for relapse and non-relapse were obtained by the time-dependent receiver operating curve analyses. Relapse-free survival (RFS) was evaluated by the Kaplan-Meier method, and between-subgroup differences in survival were analyzed by log-rank test. The prognostic significance of metabolic parameters and clinicopathological variables was assessed by a Cox proportional hazard regression analysis. The difference in the failure patterns after surgical resection was evaluated using the χ2-test.ResultsThe optimal cut-off value of TMTV for discriminating relapse from non-relapse was 3.82. The patients with a TMTV ≥3.82 showed significantly worse prognoses than those with low values (p < 0.001). The TMTV was significantly related to RFS (model 1 for preoperative risk factors: TMTV: hazard ratio [HR] =2.574, p = 0.004; model 2 for preoperative and postoperative risk factors: HR = 1.989, p = 0.044). The combination of the TMTV and cN0–1 or pN0–1 stage significantly stratified the patients into low-and high-risk recurrence groups (TMTV cN0–1, p < 0.001; TMTV pN0–1, p = 0.004). The rates of hematogenous and regional lymph node metastasis were significantly higher in the patients with TMTV ≥3.82 than those with low values (hematogenous metastasis, p < 0.001, regional lymph node metastasis, p = 0.011).ConclusionsThe TMTV was a more significantly independent prognostic factor for RFS than any other PET parameter in patients with resectable thoracic ESCC. The TMTV may be useful for the identifying thoracic ESCC patients at high risk for postoperative recurrence and for deciding the patient management.

Treatment-naïve idiopathic inflammatory myopathy: disease evaluation by fluorodeoxyglucose versus pyrophosphate

BackgroundImaging of idiopathic inflammatory myopathies (IIMs) is challenging, and no pathognomonic signs exist. Different tracers have been tested for this purpose, mainly inflammation markers including technetium-99m-pyrophosphate (PYP). We aimed to examine the utility of fluorine-18-fluorodeoxyglucose (FDG) relative to PYP in idiopathic inflammatory myopathy (IIM).MethodsUsing visual grading and CT-guided muscular segmentation and standardized uptake values (SUVs), we assessed muscular tracer uptake qualitatively and quantitatively, comparing FDG uptake in eight patients with recent-onset IIM and 24 healthy control persons and FDG and PYP uptake in seven patients.ResultsMuscular FDG and PYP uptake was increased in all patients. However, uptake distribution and signal intensity differed considerably. FDG scans revealed clear involvement of certain muscle groups including core and swallowing muscles and, in addition, abnormality in diseased extra-muscular organs. PYP was mainly visible in bones, whereas muscular PYP uptake was generally discrete and primarily located in the extremities. Quantitatively, FDG uptake was significantly higher in patients than in controls; the volume-weighted SUVmean for all right-side muscles was 0.84 versus 0.60 g/ml (95% confidence interval (CI) for mean difference 0.14–0.34, p = 0.0001). FDG SUVmean values were up to four times higher than PYP mean values in upper limb muscles (95% CI for the mean ratio 2.37–3.77, p = 0.0004) and two–three times higher in lower limb muscles (95% CI for the mean ratio 2.28–2.71, p < 0.0001).ConclusionsMuscular FDG uptake was higher in treatment-naïve IIM patients than in healthy controls and more distinct than PYP uptake in patients with a potential to reveal extra-muscular IIM involvement and malignancy. Thus, FDG appears to be superior to PYP in the diagnostic evaluation of IIM.

Hepatic superscan on fluorine-18 fluorodeoxyglucose PET/computed tomography imaging: a specific manifestation for diagnosing lymphoma or leukemia involvement.

To explore whether the markedly fluorine-18 fluorodeoxyglucose (18F-FDG) uptake in the liver (named hepatic superscan) is a specific manifestation of malignant involvement. From January 2014 to June 2019, 23 patients with such presentations were retrospectively reviewed. 18F-FDG uptake was semiquantified using maximal standardized uptake value (SUVmax), liver to cerebellum (L/C) ratio, liver to mediastinum (L/M) ratio, mean standardized uptake value (SUVmean), peak standardized uptake value (SUVpeak), metabolic tumor volume (MTV) and total lesion glycolysis (TLG). Some related laboratory examinations were also collected and analyzed. For comparison, 37 patients with mildly and moderately uptake in the liver were selected as the control group. The hepatic SUVmax, L/C ratio, L/M ratio, SUVmean, MTV and TLG of the superscan group were significantly higher than that of mild- or moderate-uptake group (P < 0.005). Malignant hematological tumors accounted for 91.3% of the superscan group, which was significantly higher than 51.4% of mild- or moderate-uptake group (P = 0.004). β2-microglobulin was observed to be significantly higher in the superscan group compared with mild- or moderate-uptake group (P < 0.001), but not lactate dehydrogenase (LDH) (P = 0.409). On the contrary, C-reactive protein (CRP) was significantly higher in mild- or moderate-uptake group than that in the superscan group (P < 0.001). Our study demonstrates that hepatic superscan is a strong indicator of malignant hematological tumors invading the liver.

Visceral adipose tissue phenotype and hypoadiponectinemia are associated with aortic Fluorine-18 fluorodeoxyglucose uptake in patients with familial dyslipidemias

BackgroundThe role of adipose tissue (AT) in arterial inflammation in familial dyslipidaemias is poorly studied. We investigated the relationship between AT and arterial inflammation in patients with heterozygous familial hypercholesterolemia (heFH) and familial combined hyperlipidemia (FCH). Methods and ResultsA total of 40 patients (20 heFH/20 FCH) and a subgroup of 20 of non-heFH/FCH patients were enrolled. Participants underwent blood sampling for serum adipokine measurements and Fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT imaging. Abdominal visceral (VAT) and subcutaneous (SAT) AT volumes and AT and abdominal aorta 18F-FDG uptake were quantified. FCH patients had increased VAT (pANOVA = 0.004) and SAT volumes (pANOVA = 0.003), lower VAT metabolic activity (pANOVA = 0.0047), and lower adiponectin levels (pANOVA = 0.007) compared to heFH or the control group. Log(Serum adiponectin) levels were correlated with aortic TBR (b = − 0.118, P = 0.038). In mediation analysis, VAT volume was the major determinant of circulating adiponectin, an effect partly mediated via VAT TBR. Clustering of the population of heFH/FCH by VAT volume/TBR and serum adiponectin identified two distinct patient clusters with significant differences in aortic TBR levels (2.11 ± 0.06 vs 1.89 ± 0.05, P= 0.012). ConclusionsVAT phenotype (increased VAT volume and/or high VAT TBR) and hypoadiponectinemia may account for the observed differences in arterial inflammation levels between heFH and FCH patients.

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

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

Triglycerides and Residual Atherosclerotic Risk

BackgroundEven when low-density lipoprotein-cholesterol (LDL-C) levels are lower than guideline thresholds, a residual risk of atherosclerosis remains. It is unknown whether triglyceride (TG) levels are associated with subclinical atherosclerosis and vascular inflammation regardless of LDL-C. ObjectivesThis study sought to assess the association between serum TG levels and early atherosclerosis and vascular inflammation in apparently healthy individuals. MethodsAn observational, longitudinal, and prospective cohort study, including 3,754 middle-aged individuals with low to moderate cardiovascular risk from the PESA (Progression of Early Subclinical Atherosclerosis) study who were consecutively recruited between June 2010 and February 2014, was conducted. Peripheral atherosclerotic plaques were assessed by 2-dimensional vascular ultrasound, and coronary artery calcification (CAC) was assessed by noncontrast computed tomography, whereas vascular inflammation was assessed by fluorine-18 fluorodeoxyglucose uptake on positron emission tomography. ResultsAtherosclerotic plaques and CAC were observed in 58.0% and 16.8% of participants, respectively, whereas vascular inflammation was evident in 46.7% of evaluated participants. After multivariate adjustment, TG levels ≥150 mg/dl showed an association with subclinical noncoronary atherosclerosis (odds ratio [OR]: 1.35; 95% confidence interval [CI]: 1.08 to 1.68; p = 0.008). This association was significant for groups with high LDL-C (OR: 1.42; 95% CI: 1.11 to 1.80; p = 0.005) and normal LDL-C (OR: 1.85; 95% CI: 1.08 to 3.18; p = 0.008). No association was found between TG level and CAC score. TG levels ≥150 mg/dl were significantly associated with the presence of arterial inflammation (OR: 2.09; 95% CI: 1.29 to 3.40; p = 0.003). ConclusionsIn individuals with low to moderate cardiovascular risk, hypertriglyceridemia was associated with subclinical atherosclerosis and vascular inflammation, even in participants with normal LDL-C levels. (Progression of Early Subclinical Atherosclerosis [PESA]; NCT01410318)

Feasibility of somatostatin receptor-targeted imaging for detection of myocardial inflammation: A pilot study

BackgroundGallium-68 Dotatate binds preferentially to somatostatin receptor (sstr) subtype-2 (sstr-2) on inflammatory cells. We aimed at investigating the potential clinical use of sstr-targeted imaging for the detection of myocardial inflammation. MethodsThirteen patients, with suspected cardiac sarcoidosis (CS) based on clinical history and myocardial uptake on recent fluorine-18 fluorodeoxyglucose (FDG) PET, were enrolled to undergo Dotatate PET after FDG-PET (median time 37 days [IQR 25-55]). Additionally, we investigated ex-vivo the immunohistochemistry expression of sstr-2 in 3 explanted sarcoid hearts. ResultsAll FDG scans showed cardiac uptake (focal/multifocal = 6, focal on diffuse/heterogeneous = 7), and 46% (n = 6) extra-cardiac uptake (mediastinal/hilar). In comparison, Dotatate scans showed definite abnormal cardiac uptake (focal/multifocal) in 4 patients, probably abnormal (heterogenous/patchy) in 3, and negative uptake in 6 cases. Similarly, 6 patients had increased mediastinal/hilar Dotatate uptake. Overall concordance of FDG and Dotatate uptake was 54% in the heart and 100% for thoracic nodal activity. Quantitatively, FDG maximum standardized uptake value was 5.0 times [3.8-7.1] higher in the heart, but only 2.25 times [1.7-3.0; P = .019] higher in thoracic nodes relative to Dotatate. Ex-vivo, sstr-2 immunostaining was weakly seen within well-formed granulomas in all 3 examined sarcoid heart specimens with no significant staining of background myocardium or normal myocardium. ConclusionOur preliminary data suggest that, compared to FDG imaging, somatostatin receptor-targeted imaging may be less sensitive for the detection of myocardial inflammation, but comparable for detecting extra-cardiac inflammation.

FDG PET/CT Findings of Castleman Disease Assessed by Histologic Subtypes and Compared with Laboratory Findings.

Castleman disease (CD) is a relatively rare lymphoproliferative disorder and the pathophysiology of the subtypes are incompletely understood. Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) demonstrates the metabolic activity of inflammatory and tumorous conditions. The FDG uptake intensity and sites of involved lesions on FDG PET/CT were assessed by histologic subtypes, and compared to the patient’s hemoglobin, platelet, albumin, and high-sensitivity C-reactive protein (hs-CRP) levels. In total, 60 PET/CT images of 44 consecutive CD patients were included: 4 (9%) unicentric and 40 (91%) multicentric; 21 (48%) hyaline vascular subtype, 16 (36%) plasma cell, and 7 (16%) mixed or unclassified. The maximum standardized uptake value (SUVmax) and tumor-to-liver (T/L) ratio of involved lymph nodes (LNs) were 5.3 ± 2.4 (range, 1.6–11.5) and 2.8 ± 1.6 (range, 1.1–9.6), respectively, with no significant difference between the histologic subtypes. Higher number of involved LN stations and presence of extra-nodal involvement on FDG PET/CT were associated with thrombocytopenia, hypoalbuminemia, and elevated hs-CRP levels (p values < 0.05). FDG-avidity was not different by histologic subtypes and did not correlate with laboratory findings. However, the extent of nodal and extra-nodal involvement as noted on FDG PET/CT was significantly associated with abnormal laboratory findings in patients with CD.

Features of IgG4-related lung disease on 18F-FDG PET/computed tomography imaging.

The aim of the study was to summarize the features of immunoglobulin G4-related lung disease (IgG4-RLD) on fluorine 18-fluorodeoxyglucose (F-FDG) PET/computed tomography (CT). In this retrospective case series, 12 consecutive patients (9 men and 3 women, mean age 55.4 ± 13.7 years) with IgG4-RLD were included. The clinicopathological information and features of F-FDG PET/CT imaging were analyzed. Six (50%) patients had pulmonary involvement alone and six (50%) patients had extrapulmonary involvement with intense F-FDG uptake. Pulmonary manifestations included mass (25%, 3/12), solid nodule (solitary 25%, 3/12; multiple 50%, 6/12), multiple ground-glass opacities (GGOs) (50%, 6/12), thickening of alveolar interstitium (50%, 6/12), and thickening of bronchovascular bundle (33.3%, 4/12). The maximum standardized uptake value (SUVmax) of the solid nodules and masses, multiple GGOs, bronchovascular bundle and the thickening of septa was 4.0 ± 2.5, 2.3 ± 1.8, 1.4 ± 0.6, and 0.9 ± 0.5, respectively. The SUVmax statistically significant linear association with the diameter of masses or solid nodules (P value = 0.03), but no significant inverse linear association (P value = 0.06) with the concentration of serum IgG4 concentration. The image patterns of IgG4-RLD on F-FDG PET/CT are varying. Multiple pulmonary manifestations or multiple organ involvement, especially in combination with elevated levels of serum IgG and IgG4, may help to make the diagnosis. A potential major application of PET-CT would be evaluation of response to treatment, and the impact of PET/CT on IgG4-RLD management is worth investigating further in the future.

Physiological Appearance of Hybrid FDG–Positron Emission Tomography/Computed Tomography Imaging Following Uncomplicated Endovascular Aneurysm Sealing Using the Nellix Endoprosthesis

Purpose: To investigate the physiological uptake of hybrid fluorine-18-fluorodeoxyglucose (FDG)–positron emission tomography/computed tomography (PET/CT) before and after an uncomplicated endovascular aneurysm sealing (EVAS) procedure as a possible tool to diagnose EVAS graft infection and differentiate from postimplantation syndrome. Materials and Methods: Eight consecutive male patients (median age 78 years) scheduled for elective EVAS were included in the prospective study (ClinicalTrials.gov identifier NCT02349100). FDG-PET/CT scans were performed in all patients before the procedure and 6 weeks after EVAS. The abdominal aorta was analyzed in 4 regions: suprarenal, infrarenal neck, aneurysm sac, and iliac. The following parameters were obtained for each region: standard uptake value (SUV), tissue to background ratio (TBR), and visual examination of FDG uptake to ascertain its distribution. Demographic data were obtained from medical files and scored based on reporting standards. Results: Visual examination showed no difference between pre- and postprocedure FDG uptake, which was homogenous. In the suprarenal region no significant pre- and postprocedure differences were observed for the SUV and TBR parameters. The infrarenal neck region showed a significant decrease in the SUV and no significant decrease in the TBR. The aneurysm sac and iliac regions both showed a significant decrease in SUV and TBR between the pre- and postprocedure scans. Conclusion: Physiological FDG uptake after EVAS was stable or decreased with regard to the preprocedure measurements. Future research is needed to assess the applicability and cutoff values of FDG-PET/CT scanning to detect endograft infection after EVAS.