Emission Tomography Findings Research Articles

¹⁸F-fluorodeoxyglucose-positron emission tomography findings are not related to cognitive functioning in service members with remote history of mild traumatic brain injury.

Determine whether glucose uptake as measured by 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging is associated with cognitive performance and cognitive deficits in active duty service members with a history of mild traumatic brain injury (mTBI). 287 patients with a history of mTBI underwent FDG-PET scans at rest and neuropsychological testing at the National Intrepid Center of Excellence at Walter Reed National Military Medical Center. Glucose uptake in the bilateral frontal, parietal, occipital, and temporal lobes, and 58 cortical/cerebellar regions were correlated with seven neuropsychological composite scores, with and without relevant covariates. Perceptual reasoning correlated with bilateral hippocampi glucose uptake (rs = .141-.165, p < .03), processing speed was inversely related to glucose uptake in the left temporal lobe (r = -.134, p = .034), and working memory was related to glucose uptake in the left parietal, temporal, and occipital lobes (rs = .128-.140, p < .05); however, these findings did not survive correction for multiple comparisons. Partial correlations between cognition and the 56 cortical/cerebellar regions of interests were not significant after correction for multiple comparisons. Glucose uptake in the left hippocampus was inversely related to the likelihood of cognitive deficits (OR = .745, p = .041); however, this did not survive correction for multiple comparisons. After correction for multiple comparisons, there was no significant relationship between regional glucose uptake and neurocognitive performance or cognitive deficits. Glucose uptake as measured by FDG-PET is not indicative of cognitive performance in active duty service members with a remote history of mTBI. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

18F‐fluorodeoxyglucose‐positron emission tomography Findings in Patients with Genetic Frontotemporal Dementia

AbstractBackgroundMutations in microtubule‐associated protein tau (MAPT), granulin (GRN), and hexanucleotide expansion repeat in the open reading frame of chromosome 9 (C9orf72) are found in 60% of familial frontotemporal dementia (FTD) cases. The current study aims to delineate brain regions with reduced glucose metabolism in patients with genetic FTD in comparison with cognitively normal controls.Methods(18)F‐ fluorodeoxyglucose (FDG)‐positron emission tomography (PET) images were retrospectively obtained from 17 genetic FTD patients. All patients were symptomatic at the time of imaging, and the autopsy was available for 13. Pittsburgh compound B (PiB) amyloid PET scans were done for 13 patients (Table 1). FDG‐PET was collected at Lawrence Berkeley National Laboratory on a PET or PET‐CT scanner as six 5‐min frames acquired 30 min post tracer injection. Standard Uptake Value Ratio (SUVR) images were created for each patient using pons as a reference region. W‐score (age‐adjusted Z‐score) maps were created for each patient’s FDG SUVR using a group of neurologically unimpaired controls (N=74, Mean age 65+16, 41 female) as reference.ResultOn review of single‐subject w‐maps, all patients with MAPT mutation showed hypometabolism in the anteromedial temporal lobes with 66% showing anterolateral temporal hypometabolism and 33% in the frontal and dorsolateral parietal lobes. Hypometabolism in temporal lobes was seen in all GRN patients and 75% had frontal and parietal hypometabolism in an asymmetric pattern. 80% of theC9orf72 patients had hypometabolism in anteromedial temporal and orbitofrontal regions. 60% showed hypometabolism in dorsolateral prefrontal, medial frontal, and anterolateral temporal lobes. Posterior temporal, posterior cingulate, parietal lobe, cerebellum, insula, thalamus, and caudate were hypometabolic in less than 40% of the C9orf72 patients (Figure 1).On group‐level analysis, compared to controls, patients with C9orf72 showed hypometabolism in the frontotemporal regions, cerebellum and thalamus. Hypometabolism in the frontotemporal and parietal regions was seen with GRN mutation. MAPT mutation carriers showed frontal and anteromedial temporal hypometabolism (Figure 2).ConclusionHypometabolism in the posterior regions and cerebellum is more suggestive of C9orf72 repeat expansion. An asymmetric pattern of hypometabolism was seen in all GRN mutation carriers. MAPT mutation resulted in a greater degree of hypometabolism in the anterior medial temporal lobes.

Feasibility study of finalizing the extended adjuvant temozolomide based on methionine positron emission tomography (Met-PET) findings in patients with glioblastoma

In the management of patients with newly diagnosed glioblastoma, there is no standard duration for adjuvant temozolomide treatment. This study aimed to assess the feasibility of finalizing adjuvant temozolomide treatment on the basis of methionine uptake in methionine positron emission tomography (Met-PET). We conducted a retrospective review of glioblastoma patients who underwent more than twelve cycles of temozolomide (extended temozolomide) treatment after resection and concomitant chemoradiotherapy with no evidence of recurrence on MRI. In addition to the methionine uptake value at the completion of extended temozolomide, local and distant recurrence and progression-free survival were also analyzed. Forty-four patients completed the extended temozolomide treatment. Among these, 18 experienced some type of tumor recurrence within one year. A Tmax/Nave value of 2.0 was the optimal cut-off value indicating progression. More than 80% of the patients with low methionine uptake completed the temozolomide treatment, and subsequent basic MRI observations showed no recurrence within one year after Met-PET. Subgroups with high uptake (≥2.0), even with continuation of temozolomide treatment, showed more frequent tumor progression than patients with low uptake (<2.0) who completed the extended temozolomide treatment (p < 0.001, odds ratio 14.7, 95% CI 3.46–62.3). The tumor recurrence rate increased in stepwise manner according to methionine uptake. Finalization of the extended temozolomide treatment on the basis of low uptake value was feasible with a low recurrence rate. Compared to MRI, Met-PET shows better ability to predict tumor progression in long-term glioblastoma survivors with extended temozolomide use.

Excellence in non-small cell lung cancer staging by endobronchial-TBNA: Comparison with PET-CT and surgery

Objective: To determine the correlation and/or discrepancies between positron emission tomography (PET-CT) findings, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and surgery in the staging of non-small cell lung carcinoma.Material and methods: Data were evaluated retrospectively from a prospective interventional endoscopy database. Positive results with EBUS-TBNA was the first end point and all cytology negatives were confirmed with mediastinoscopy/surgery.Results: Four hundred and eighty three patients were included and 1017 lymph nodes (LNs) were sampled in the study. One hundred and twenty eight LNs were excluded (positive with EBUS-TBNA). Four hundred and sixty five LN (52.3%) were found benign with EBUS-TBNA; however, only 15 of these were confirmed to be malignant by surgery (1.7%). The sensitivity, specificity, PPV, NPV and diagnostic accuracy of EBUS-TBNA were 96.5, 100, 100, 96.7 and 98.3%, respectively. The sensitivity, specificity, PPV, NPV and diagnostic accuracy of PET-CT for maximum standardized uptake value (SUVmax) 2.5 were 90.1, 29.2, 55.3, 75.4, 59.2%, respectively. A cut-off SUVmax of 5.2 was detected with 74.8% sensitivity, 84% specificity, 82.0% PPV, 77.5% NPV and 79.5% accuracy (area under the curve (AUC) of 0.818, 95% CI 0.791–0.843, p<.001).Conclusion: EBUS is a reliable, repeatable and safe technique with a high diagnostic accuracy and should be performed quickly to avoid superfluous time loss in the staging of lung cancer.AbbreviationsPET-CTF-18 fluorodeoxyglucose positron emission computed tomographyNSCLCNon-small cell lung cancerEBUS-TBNAEndobronchial ultrasound-guided transbronchial needle aspirationSUVmaxMaximum standardized uptake valueLNsLymph nodesTTF-1Thyroid transcription factor-1H&EHematoxylin and eosin; Med: MediastinoscopyVATSVideo associated thoracic surgeryAUCArea under curveOROdds ratioCIConfidence intervals

(18F)-FDG Positron Emission Tomography and Magnetic Resonance Imaging Findings in Differential Diagnosis of Multiple Primary Central Nervous System Lymphomas: A Case Report

(18F)-FDG Positron Emission Tomography and Magnetic Resonance Imaging Findings in Differential Diagnosis of Multiple Primary Central Nervous System Lymphomas: A Case Report

Posttransplant Lymphoproliferative Disorder of the Thorax: CT and FDG-PET Features in a Single Tertiary Referral Center.

To investigate the chest computed tomography (CT) and F-18 fluoro-2-deoxy-d-glucose positron emission tomographic (FDG-PET) findings of posttransplant lymphoproliferative disorder (PTLD) in the thorax.From November 2004 to February 2013, the cases of 12 adult patients (3 female and 9 male, age range 34–68, and median age 46 years) with proven PTLD were retrospectively reviewed. The transplanted organs included the kidney (5/12), liver (4/12), heart (1/12), combined kidney and pancreas (1/12), and hematopoietic stem cell (1/12). We investigated the relationship of the Epstein–Barr virus (EBV) to the patients’ long-term follow-up, and evaluated the characteristics of the lesions on the chest CT and FDG-PET. The lesions were classified into 2 patterns: that of lymph node and lung involvement.The interval between the transplantation and the onset of PTLD was 2 to 128 months (median, 49). Positive EBV-encoded RNA in the pathologic specimens was found in 10 patients (83.3%). Eight patients were positive for EBV PCR in their blood, and 3 patients showed seroconversion without antiviral therapy. The responses to treatment were complete in 7 cases (58.3%), partial remission in 4 cases (33.3%), and undetermined in 1 case (8.3%). The more common chest CT patterns showed lymph node involvement (10/12) rather than lung involvement (3/12). The median maximum-standardized uptake value on the FDG-PET scans was 7.7 (range, 2.7–25.5).In patients with PTLD involving the thorax, lymphadenopathy was the more common manifestation on the chest CT rather than lung involvement. The lesions showed hypermetabolism on FDG-PET.

Merkel Cell Carcinoma of the Axilla and Adrenal Gland: A Case Report with Imaging and Pathologic Findings.

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine carcinoma of the skin. MCC is characterized by a high incidence of locoregional recurrence, and distant metastasis, and often requires short-term follow-up after treatment. In this present paper, we describe a rare case of MCC, which presented as a palpable axillary mass and an incidental adrenal mass, and report on the ultrasonography, computed tomography, and 18F-fluorodeoxyglucose-positron emission tomography findings. The patient underwent surgery and adjuvant radiation therapy. Seven months after the initial diagnosis, distant metastasis was detected during a follow-up examination.

A Solitary Mixed Squamous Cell and Glandular Papilloma of the Lung

Mixed squamous cell and glandular papilloma (mixed papilloma) of the lung is exceedingly rare, with only 18 cases reported in the literature. Herein, we report a case of mixed papilloma and its associated immunohistochemical and positron emission tomographic (PET) findings. A 60-year-old Japanese male with a smoking history of 40 pack-years presented with a smooth-edged pulmonary lesion in the right S5 segment on computed tomography (CT). F18-fluorodeoxyglucose (FDG) PET revealed abnormally increased FDG uptake in the mass (maximum standardized uptake value, 3.4). We performed right middle lobectomy and combined partial resection of the S8 segment. The 1.8-cm tumor that filled the enlarged lumen of the B5b was histologically diagnosed as mixed papilloma. Immunohistochemically, the pseudostratified columnar epithelium was positive for cytokeratin (CK) 5/6 and CK7. p40 positivity was predominant in the basal and squamous cells. Thyroid transcription factor-1 and carcinoembryonic antigen were negative on immunostaining. Malignant features were absent. The postoperative course has been uneventful for 3 months after the surgery. No recurrences were reported after the surgical resection of the mixed papilloma. Therefore, surgical resection may be considered the mainstay of curative treatment.

Influence of left ventricular geometry on thallium-201 gated single-photon emission tomographic findings in patients with known or suspected coronary artery disease

Recent studies have shown good correlations between echocardiography and Tl-201 gated single-photon emission computed tomography (SPECT) for the assessment of left ventricular volumes and ejection fraction. We assessed how left ventricular geometry affected correlations between these values measured by the 2 methods in patients with known or suspected coronary artery disease. There were 109 patients with normal left ventricular geometry, 20 patients with concentric remodeling, 32 patients with eccentric hypertrophy and 28 patients with concentric hypertrophy. In all 4 groups, there were good correlations between end-diastolic volume (EDV) and end-systolic volume (ESV) values measured by echocardiography and quantitative gated SPECT (QGS). EDV and ESV values measured by QGS were significantly underestimated than those measured by echocardiography except for ESV in eccentric hypertrophy. In all 4 groups, ejection fraction (EF) value measured by echocardiography significantly correlated with that measured by QGS, but Bland-Altman plot showed a proportional error. EF value measured by QGS was likely to be overestimated when EF value increased from the median value, and to be underestimated when EF value decreased from the median value especially in concentric remodeling. Tl-201 gated SPECT is a useful tool for the assessment of left ventricular volumes and function, but it requires methodological considerations according to left ventricular geometry.

Prognostic nomogram for diffuse large B‐cell lymphoma incorporating the International Prognostic Index with interim‐positron emission tomography findings

Results from interim-positron emission tomography (PET) studies in diffuse large B-cell lymphoma (DLBCL) patients are varied. We evaluated the prognostic value of interim-PET in our centre. To improve concordance, interim-PET was combined with the International Prognostic Index (IPI). We retrospectively reviewed 100 new consecutive DLBCL patients treated with immunochemotherapy from 2005 to 2010. Twenty-four patients did not receive interim-PET and were excluded. Interim-PET images were re-examined using a qualitative assessment technique. Progression-free survival (PFS) and overall survival (OS) were analysed by the Cox proportional hazards model and prognostic accuracy was assessed using Harrell's C statistics (C). Eleven patients were positive, and 65 were negative at interim-PET. The 2-year OS and PFS were 70.8% and 60.0%, respectively, in the PET-negative group, 36.4% and 36.4% for the PET-positive group (log-rank P-value 0.0008 for PFS, 0.0001 for OS). The IPI and interim-PET were minimally correlated. On Cox regression analysis, both were significant indicators of PFS (P < 0.001 and P = 0.002 respectively). The prognostic accuracy for PFS of a negative PET result was limited (C = 0.63), as it was for IPI (C = 0.75), but with the two indicators combined, the predictive accuracy was improved (C = 0.81). A nomogram, predictive for relapse-free survival at 2 years, was constructed. In DLBCL patients treated with immunochemotherapy, the IPI and interim-PET provide independent prognostic information. In combination, a more powerful predictive model may be created as a nomogram. This can be refined in prospective trials and may help clinical decision making.

Testosterone effect on brain metabolism in elderly patients with Alzheimer’s disease: comparing two cases at different disease stages

To describe the effect of testosterone replacement therapy (TRT) on the brain activity of two demented, hypogonadal male patients with early and late-stage Alzheimer's disease (AD), respectively. We describe the clinical and positron emission tomography (PET) findings for two individuals, one with early stage and the other with late-stage Alzheimer's disease, before and after treatment with a topical testosterone gel. Both patients were hypogonadal at baseline. We assessed cerebral glucose metabolism (CGM) via (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET). We investigated whether there are testosterone-susceptible areas within cerebral structures in patients with Alzheimer's disease. Under testosterone replacement therapy, changes in cerebral glucose metabolism were observed in both patients. Improvement in glucose uptake was observed most consistently in the parietal lobe and brainstem; decreased glucose metabolism was observed in the temporal lobe, the limbic system and the insula for these two subjects. These case reports demonstrate the potential for PET scanning to detect changes in cerebral glucose metabolism in hypogonadal men with Alzheimer's disease who are treated with testosterone. Further study will be needed to investigate the consistency and significance of these changes in terms of magnitude and brain region, and the correlation with functional changes.

The pathological features of FDG-PET negativity in patients with pancreatic ductal carcinoma

Introduction: Usefulness of FDG-PET in pancreatic cancer various studies have been carried out. Aims: In this study, we clarified the pathological features of pancreatic ductal carcinoma with negative positron emission tomography(PET) findings and determined the factors that might affect fluorodexyglucose(FDG) accumulation by the pancreatic ductal carcinoma. Patients & methods: Eighteen patients with pancreatic ductal carcinoma and negative findings on PET preoperatively enrolled. Pathological findings (proliferation type and extent of fibrosis) and reproductive activity were examined. Proliferation was classified into 3 types: equal, extended, and collective. Reproductive activity was assessed using the Ki67 index; the Ki-67 indexes for 11 patients with positive PET findings were used as controls. Results: There were 10, 3, and 5 patients with equal, extended, and collective proliferation, respectively. Patients with equal and extended proliferation generally had massive fibrosis. The difference in proliferation type could not be determined by the Ki-67 index, which ranged from 2.7 to 12.6(average, 6.8). The average Ki-67 index of patients with PET positivity was 26.1(p<0.01) Conclusion: PET negativity can be defined by proliferation type; patients with equal and extended proliferation accounted for 72%(13/18) of the patients. These results suggest that low cell density, fibrosis, and extension cancer gland indicate a decrease in the amount of localized cancer cells. The decrease in the number cancer cells caused a reduction in FDG accumulation, which possibly lead to PET negativity. Patients with PET negativity had a lower rate of Ki-67 positivity than patients with PET positivity. It was hypothesized that the reproductive activity of the cancer cells also contributes to PET negativity.

O4‐01‐02: Meta‐analytic comparison of PiB‐PET and FDG‐PET results in Alzheimer's disease and MCI

We conducted a meta-analysis of positron emission tomography (PET) findings in Alzheimer’s disease (AD) and mild cognitive impairment (MCI) to clarify the changes underpinning these conditions. All studies that utilised the PET tracers Pittsburgh Compound-B (PIB) or 2-[18F]fluoro-2-deoxy-d-glucose (FDG) to investigate patients with MCI or AD, were considered for the meta-analysis. Meta-analyses of PIB-PET and FDG-PET changes between patients and controls were undertaken with the effect-size signed differential mapping (ES-SDM) voxel-based meta-analytic method. A total of 24 studies were included involving 728 AD patients, 211 MCI patients and 658 healthy controls. Individuals with AD showed a significant PIB retention in bilateral precuneus and temporal, supramarginal, cingulate and fusiform gyri, as well as right insula and putamen. In addition, AD patients showed significant glucose hypometabolism in bilateral precuneus and temporal, supramarginal, cingulate, fusiform, angular, inferior parietal and middle frontal gyri, as well as left precentral and parahippocampal gyri and right superior frontal gyrus and thalamus. An exploratory meta-analysis of the few studies on MCI showed mildly decreased glucose metabolism with a similar regional distribution than in patients with AD. We suggest that our results can be used for further region-of-interest studies of AD and MCI patients.

Solitary fibrous tumor of the buccal space resected in combination with coronoidectomy

Solitary fibrous tumor (SFT) is an uncommon spindle-cell mesenchymal tumor of probable fibroblastic derivation that most often occurs in the pleura, where it is typically benign. This report describes a case of a large SFT that arose in the buccal space, and includes computerized tomography, magnetic resonance imaging, and positron emission tomography (PET) findings. (18)F-Fluorodeoxyglucose (FDG) PET axial imaging showed weak abnormal accumulation of FDG in the left buccal region. The tumor was located behind the posterior wall of the maxilla, adjacent to the medial aspect of the coronoid process and was compressed between the coronoid and maxillary alveolar processes. We resected it with the use of a transoral approach in combination with coronoidectomy. Coronoidectomy was chosen because it facilitated safe removal of the tumor by improving its visibility and providing enough working space to resect it through a transoral approach.

Non–Small Cell Lung Cancer: Prognostic Importance of Positive FDG PET Findings in the Mediastinum for Patients with N0–N1 Disease at Pathologic Analysis

To assess the prognostic implications of mediastinal positron emission tomographic (PET) findings in patients undergoing curative resection of non-small cell lung cancer (NSCLC) who have histologically negative mediastinal lymph nodes (LNs), with the hypothesis that positive findings at PET are prognostic even in patients with negative histologic findings in the LNs. Records of patients with a preoperative PET undergoing curative surgery, without adjuvant radiation, for pathologic T1-3N0-1 NSCLC at the University of North Carolina between 2000 and 2006 were reviewed as an institutional review board-approved HIPAA-compliant retrospective study. Ninety patients were evaluable (all histologically negative in mediastinum; 44 with both mediastinoscopy and surgery); 13 patients had positive mediastinal PET findings, and 77 had negative mediastinal PET findings. Local-regional and distant failure rates in patients with and those without mediastinal abnormalities at preoperative PET were compared by using logistic regression and log-rank tests. Median follow-up was 54.3 months (range, 1-99 months). There were higher rates of local-regional (P = .001) and distant (P < .001) failure as well as death (P = .001) in patients with postive PET findings than in patients with negative findings. In multivariable analysis (adjusting for other prognostic factors), positive PET findings in the mediastinum remained prognostic for distant failure (P < .001, hazard ratio = 6.9) and were marginally prognostic for local-regional failure (P = .093, hazard ratio = 1.9). Positive findings at preoperative PET in the mediastinum appear to have prognostic implications despite the mediastinal LNs being histologically negative. The high rate of local-regional and distant failure suggests that postoperative radiation therapy and/or chemotherapy may be particularly helpful in patients with positive mediastinal findings at preoperative PET.

Intensely Positron Emission Tomography-avid Benign Adrenal Adenoma

Both positron emission tomography/computed tomography (CT) and adrenal washout studies are highly accurate in differentiating benign from malignant adrenal lesions. Very few data exist to help guide management when the positron emission tomography and CT adrenal findings contradict each other with regard to the malignant potential. We present a patient with a remote history of breast cancer and a new solitary left adrenal mass. A CT washout study suggested a lipid-poor adenoma; however, positron emission tomography/CT demonstrated intense fluorodeoxyglucose uptake, suggesting malignancy. The pathologic evaluation after laparoscopic adrenalectomy revealed a benign adrenal adenoma.

An IgG4-Related Salivary Gland Disorder: A Case Series Presenting with a Different Clinical Setting.

Küttner tumor is a chronic inflammatory disease that presents with a firm swelling of the submandibular gland and often mimics a neoplasm. Recently evidence suggests that Küttner tumor may be a type of disorder characterized by IgG4-related inflammations. Herein, we report 3 cases of submandibular gland swellings with severe fibrosis, inflammation with marked lymphoplasmacytic infiltration; this pathology mimics clinical manifestation of a malignant tumor in 18-fluorodeoxyglucose positron emission tomography (FDG-PET) findings.

Usefulness of 18F-fluorodeoxyglucose positron emission tomography for diagnosis of asymptomatic giant cell arteritis in a patient with Alzheimer's disease

It is often difficult to diagnose disease in elderly patients, in particular those with dementia, who do not present with typical symptoms. This report describes our experience of an elderly patient (an 83-year-old woman) who presented with a chief complaint of memory loss, showed a marked inflammatory response, and was diagnosed with large-vessel giant cell arteritis (GCA) on the basis of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) findings. She had no symptoms typical of GCA including jaw claudication, visual field defect and heavy headed feeling. Corticosteroid therapy resulted in a trend toward improvement in the inflammatory response and then she first recognized that she might have experienced slight dull headache before treatment of GCA. This was probably because this patient had large-vessel GCA, which produces a few symptoms in the head and neck, and because she had Alzheimer's disease and could not accurately describe her symptoms. Our experience suggests the usefulness of FDG-PET for the diagnosis of GCA, particularly in elderly patients without typical symptoms.

Sclerosing Angiomatoid Nodular Transformation of the Spleen

Sclerosing angiomatoid nodular transformation of the spleen is a recently recognized benign vascular lesion, characterized microscopically by multiple angiomatoid nodules embedded within a fibrosclerotic stroma. Although its imaging manifestations have been limited in the radiologic literature, features such as low-level increased fluorodeoxyglucose activity on a positron emission tomographic scan, near-complete blending in with normal splenic parenchyma on a delayed-phase image, and the presence of radiating scarring on a magnetic resonance image may suggest the diagnosis. We report here the computed tomographic, magnetic resonance imaging, and positron emission tomographic findings of sclerosing angiomatoid nodular transformation, along with gross and microscopic pathological correlation.

A Pulmonary Sclerosing Hemagioma with an Increasing Uptake on PET

Pulmonary sclerosing hemangioma is a relatively rare neoplasm of the lung. Although there have been five previous case reports that address the 18-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) findings in a sclerosing hemangioma of the lung, no report has demonstrated an interval change in the FDG-PET findings. This report describes a case of pulmonary sclerosing hemangioma which presented with an increase of uptake of FDG-PET after about one years' follow-up.