Clinical value of a high-fat and low-carbohydrate diet before FDG-PET/CT for evaluation of patients with suspected cardiac sarcoidosis.

BACKGROUND: We hypothesized that a high-fat and low-carbohydrate (HFLC) diet before FDG-PET/CT could identify patients with active cardiac sarcoidosis (CS). METHODS: Fifty-eight sarcoidosis patients with a suspicion of CS consumed a HFLC diet before FDG-PET/CT. Clinical, electrical, and other imaging investigations were compared to PET results. RESULTS: Using Japanese Ministry of Health and Welfare (JMHW) criteria as a gold standard, 21% (12/58) of patients had a CS. Sensitivity and specificity of PET (visual analysis) were 83% (10/12) and 78% (36/46), respectively, with a very good interobserver agreement (k = 0.86). 70% (7/10) of the patients with a positive PET and negative JMHW criteria exhibited abnormalities suggestive of CS either on MR (n = 3) or SPECT (n = 4). Comparison with the presence of delayed enhancement on magnetic resonance imaging helped to classify patients with active (PET positive) or non-active CS (PET negative). In addition, when MR and PET were both negative, none of the patients met the JMHW criteria. PET response under treatment was concordant with clinical evolution in 11/13 patients. CONCLUSIONS: FDG-PET/CT after HFLC diet is a sensitive tool for the diagnosis of active CS. Combined use of PET and MR is promising for the detection and characterization of CS lesions.

[Current applications of PET/CT]. / Indications de la tomographie par émission de positons: où en est-on?

Positron emission tomography/computed tomography (PET/CT) is a sensitive method for detecting, staging, and therapy monitoring of many malignancies. It has modified the management of cancer. PET/CT allows for a "whole body" assessment of a metabolic process, depending on the type of tracer, combined with a CT scan. In the present article we review the different PET tracers available today and the most effective applications of PET-CT in oncology, but also in inflammatory diseases, heart diseases and dementia.

18 F-FDOPA PET/CT of Paraganglioma in the Spermatic Cord.

ABSTRACT: A 53-year-old man with chronic kidney failure was referred to perform an 18 F-FDOPA PET/CT to characterize a mass located on the right spermatic cord. Previously, the pathological analysis of CT-guided biopsies suggested paraganglioma or metastatic lesion of pheochromocytoma. Serum normetanephrine and serum metanephrine values were respectively 2- and 1.5-fold greater than the normal upper limit, which could be explained by the chronic kidney failure. PET/CT images revealed intense 18 F-FDOPA uptake of the mass without any other pathological findings, suggesting the diagnosis of paraganglioma. Pathological examination of surgical specimen confirmed the diagnosis of paraganglioma of the spermatic cord, which is exceptional.

Aortitis PET Imaging in VEXAS Syndrome: A Case Report.

ABSTRACT: VEXAS (vacuoles, E1 enzyme, X-LINKED, autoinflammatory, somatic) syndrome is a complex inflammatory disease associated with somatic mutations of the ubiquitin-like modifier activating enzyme 1 (UBA1) gene. A 75-year-old man with a medical history of thrombophlebitis, leukocytoclastic vasculitis, chronic inflammatory arthralgia, elevated inflammatory markers, and anemia was diagnosed with VEXAS syndrome. 18F-FDG PET/CT showed thoracic aortitis, a rare involvement during VEXAS syndrome. Corticosteroid therapy monitored with 18F-FDG PET/CT led to a complete metabolic response.

Comparison of FDG-PET/CT and MR with diffusion-weighted imaging for assessing peritoneal carcinomatosis from gastrointestinal malignancy.

OBJECTIVES: To assess the accuracy of FDG-PET/CT and MR with diffusion-weighted imaging (MR-DWI) for diagnosing peritoneal carcinomatosis (PC) from gastrointestinal malignancies. METHODS: Thirty consecutive patients referred for staging of gastrointestinal malignancy underwent FDG-PET/CT and MR-DWI in this retrospective study. Extent of PC was characterised by dividing the peritoneal cavity into three sites in each patient: right and left supramesocolic areas and inframesocolic level (total 90 sites). Presence of PC was confirmed either by surgery (18/30) or by follow-up (12/30). RESULTS: PC was confirmed in 19 patients (19/30). At a total of 90 sites, 27 showed proven PC. On a patient-based analysis, sensitivity, specificity, PPV, NPV and accuracy were respectively 84%, 73%, 84%, 73% and 80% for PET/CT and 84%, 82%, 89%, 75% and 83% for MR-DWI. On a site-based analysis, overall sensitivity and specificity of PET/CT (63%, 90%) and MR-DWI (74%, 97%) were not statistically different (P = 0.27). In the supramesocolic area, MR-DWI detected more sites involved than PET/CT (7/9 vs. 4/9). The sensitivities of PET and MR were lower for subcentimetre tumour implants (42%, 50%). Interobserver agreement was very good for PET/CT and good for MR-DWI. CONCLUSIONS: FDG-PET/CT and MR-DWI showed similar high accuracy in diagnosing PC. Both techniques underestimated the real extent of PC because of decreased sensitivity for subcentimetre lesions. KEY POINTS: FDG-PET/CT and MR-DWI showed similar high accuracy for diagnosing peritoneal carcinomatosis. • In the supramesocolic area, MR-DWI could be more sensitive than PET/CT. • Both techniques showed lower sensitivity for subcentimetre lesions. • Interobserver agreement was very good for PET/CT and good for MR-DWI.

Clinical and Radiological Follow-Up of a Pfizer-BioNTech COVID-19 Vaccine-Induced Hemichorea-Hemiballismus.

Background: Hemichorea-hemiballismus is a rare hyperkinetic movement disorder. Case Report: A 90-year-old male developed left hemichorea-hemiballismus after his second dose of the Pfizer-BioNTech COVID-19 vaccine. A wide range of investigations including magnetic resonance imaging did not reveal an alternative cause. [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed increases in right putamen fixation compared to the left side. The patient showed significant improvement after five days of intravenous corticosteroids, with a normal FDG-PET. Discussion: This hemichorea-hemiballismus case shows dynamic restoration of putamen metabolism mirroring clinical evolution after administration of corticosteroids, suggesting an autoimmune COVID-19 vaccine-induced reaction.

Antibiotics administration during last trimester of pregnancy is associated with atopic dermatitis - a cross-sectional study.

INTRODUCTION: Studies regarding antibiotics administration during pregnancy and atopic dermatitis (AD) in children are only few. In this context, the objective of our study was to investigate the potential association between the timing of intrauterine exposure to antibiotics or prenatal antibiotic administration in general and AD occurrence in children. METHODS: This was a cross-sectional study in 1046 subjects. The exposure to antibiotics during pregnancy was initially evaluated using simple logistic regressions. Then, each period of antibiotics administration was adjusted with the other periods of antibiotics exposure (model 1) and with the other variables associated with AD in our database (model 2). RESULTS: In simple logistic regression analysis, the administration of antibiotics during pregnancy, as a whole period, presented a trend of association with AD (OR = 1.28, %CI: 0.99 - 1.65). When we analyzed antibiotic administration during each trimester of pregnancy, only antibiotherapy during the 3rd trimester was associated with AD (OR = 2.94, %CI: 1.21 - 7.12). After adjusting with all the other important risk factors associated with AD in the database, antibiotics administration during the 3rd trimester of pregnancy was still independently associated with AD (OR=2.64, %CI: 1.01 - 6.91). CONCLUSION: Antibiotic administration during the 3rd trimester of pregnancy was independently associated with AD in children.

Tonsillar lymphoma masquerading as obstructive sleep apnea - pediatric case report.

The commonest cause of head and neck malignancy in pediatric patients is lymphoma. A particular case is the tonsillar lymphoma. Even though unilateral tonsillar enlargement represents an ominous sign for neoplasia, clinical manifestations vary and are non-specific. Therefore, a delayed diagnosis is performed which compromises optimal therapy and hinders the prognosis. We present the case of a 5-year-old boy who was initially diagnosed with obstructive sleep apnea, without reported systemic complaints. Asymmetric tonsillar hypertrophy created the premises for performing a tonsillectomy to rule out malignancy. The pathological evaluation of the resected tonsils revealed a malignant non-Hodgkin's lymphoma, with immunophenotypic features consistent with sporadic type Burkitt lymphoma. The aim of this paper is to emphasize the importance of the histopathological examination and of the immunohistochemistry testing for the prompt and accurate diagnosis of all asymmetric tonsillar hypertrophy in children undergoing tonsillectomy. Furthermore, immunohistochemical diagnosis is vital for establishing a personalized multi-agent chemotherapy regimen, which dramatically improves the survival rate. We recommend histopathological evaluation in all children with asymmetric tonsillar hypertrophy undergoing tonsillectomy for various reasons. Needless to say, it is better to be cautious and exclude the presence of tonsillar lymphoma, than to confront with the severe consequences of misdiagnosis.

Expression Profile of p53 and p21 in Large Bowel Mucosa as Biomarkers of Inflammatory-Related Carcinogenesis in Ulcerative Colitis.

Ulcerative colitis (UC) is a chronic, relapsing inflammatory bowel disease that slightly increases the risk of colorectal cancer in patients with long-standing extended disease. Overexpression of p53 and p21 in colonic epithelia is usually detected in UC patients when no dysplasia is histologically seen and it is used by pathologists as a discriminator between regenerative changes and intraepithelial neoplasia, as well as a tissue biomarker useful to predict the risk of evolution toward malignancy. We present a one-year prospective observational study including a cohort of 45 patients with UC; p53 and p21 were evaluated in epithelial cells. p53 was positive in 74 samples revealed in 5% to 90% of epithelial cells, while 63 biopsies had strong positivity for p21 in 5% to 50% of epithelial cells. Architectural distortion was significantly correlated with p53 overexpression in epithelial cells. Thus, we consider that architectural distortion is a good substitute for p53 and p21 expression. We recommend use of p53 as the most valuable tissue biomarker in surveillance of UC patients, identifying the patients with higher risk for dysplasia. Association of p21 is also recommended for a better quantification of risk and for diminishing the false-negative results.

Management of large-vessel vasculitis with FDG-PET: a systematic literature review and meta-analysis.

We aimed to clarify the role of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in the management of large-vessel vasculitis (LVV), focusing on 3 issues which are as follows: describe and determine the different FDG-PET criteria for the diagnosis of vascular inflammation, the performance of FDG-PET for the diagnosis of large-vessel inflammation in giant cell arteritis (GCA) patients, and the performance of FDG-PET to evaluate the disease inflammatory activity in Takayasu arteritis (TA) patients. MEDLINE, Cochrane Library, and EMBASE database were searched for articles that evaluated the value of FDG-PET in LVV, from January 2000 to December 2013. Inclusion criteria were American College of Rheumatology criteria for GCA or TA, definition PET positivity threshold, and >4 cases included. Sensitivity (Se) and specificity (Sp) of FDG-PET for the diagnosis of large-vessel inflammation were calculated from each included individual study, and then pooled for meta-analysis with a random-effects model. Twenty-one studies (413 patients, 299 controls) were included in the systematic review. FDG-PET showed FDG vascular uptake in 70% (288/413) of patients and 7% (22/299) of controls. Only vascular uptake equal to or higher than the liver uptake was significantly different between GCA/TA patients and controls (P < 0.001). The meta-analysis of GCA patients (4 studies, 57 patients) shows that FDG-PET has high Se and Sp for the diagnosis of large-vessel inflammation in GCA patients in comparison to controls, with a pooled Se at 90% (95% confidence interval [CI], 79%-93%) and a pooled Sp at 98% (95% CI, 94%-99%). The meta-analysis of TA patients (7 studies, 191 patients) shows that FDG-PET has a pooled Se at 87% (95% CI, 78%-93%) and Sp at 73% (95% CI, 63%-81%) for the assessment of disease activity in TA, with up to 84% Sp, with studies using National Institutes of Health criteria as the disease activity assessment scale. FDG-PET showed good performances in the diagnosis of large-vessel inflammation, with higher accuracy in GCA patients than in TA patients. Although a vascular uptake equal to or higher than the liver uptake appears to be a good criterion for the diagnosis of vascular inflammation, further studies are needed to define the threshold of significance as well as the clinical significance of the vascular uptake.

FDG-PET/CT in patients with ANCA-associated vasculitis: case-series and literature review.

OBJECTIVES: We aimed to assess the clinical value of FDG-PET/CT in patients with ANCA-associated vasculitis. MATERIALS AND METHODS: We retrospectively included 16 patients with ANCA-associated vasculitis who underwent 21 FDG-PET/CT between 2009 and 2013, in 2 university hospitals from the Paris suburb area. All FDG-PET/CTs were retrospectively analyzed and compared to clinical, biological and conventional imaging data at baseline and during the follow-up. RESULTS: ANCA-associated vasculitis was granulomatosis with polyangiitis (GPA, n=10), microscopic polyangiitis (MPA, n=4), and eosinophilic GPA (EGPA, n=2). PET was performed at initial presentation in 14 cases and during the follow-up in 7 cases. At baseline, PET was positive in 100% of GPA patients (8/8) and in 50% (3/6) of patients with other ANCA-vasculitis (p=0.05). FDG uptake tended to be higher in patients with GPA in comparison to patients with MPA/EGPA (median SUVmax: 5 versus 2.5; p=0.08). Sinonasal, lung, cardio-vascular and kidney involvements were all accurately identified by PET, except in one MPA patient with glomerulonephritis. As expected, skin, joint, eye and peripheral nervous system impairments were not detected by PET. No occult site was detected by PET, except in 2 salivary gland FDG uptake without clinical abnormalities. Patients with GPA exhibited a higher number of positive sites on PET (2 [1.75-2.25] versus 0.5 [0-1], p=0.006) than patients with MPA/EGPA. In pooled data including our study and the literature data of GPA patients (n=31), SUVmax was associated with Birmingham Vasculitis Activity Score (BVAS) (r=0.49; p=0.03). CONCLUSION: FDG-PET/CT accurately identifies organ localizations in GPA, other than in nervous system, eye and skin, but do not bring additional benefit to the usual organ screening. The value of FDG-PET/CT in other ANCA-associated vasculitis need to be further addressed.

18F-fluorodeoxyglucose positron emission tomography/computer tomography as an objective tool for assessing disease activity in Sjögren's syndrome.

OBJECTIVE: This study aims to determine the value of FDG-PET/CT to assess disease activity in patients with Sjögren's syndrome (SS). METHODS: Thirty-two patients with SS who underwent PET/CT were retrospectively analyzed. PET/CT activity score was measured using a 6-point scale including the 6 following items (0/1: absence or presence of an item): lymphadenopathy on CT, high-resolution CT (HRCT) evidence of interstitial lung disease (ILD), parotid glands SUVmax >3, submandibular glands SUVmax >3, lymph node uptake, ILD uptake. Combined PET/CT score was correlated to ESSDAI (EULAR Sjögren's Syndrome Disease Activity Index) score and other parameters of SS activity. RESULTS: Pathological FDG uptake was observed in 75% of patients (24/32): lymph-nodes (n=19, 60%), salivary glands (n=17, 53%), lungs (n=9, 28%), and thyroid (n=2). Median ESSDAI and PET/CT activity scores were 9.5 [5-12] and 2 [0-3], respectively. PET/CT activity score correlated with ESSDAI (r=0.49, p=0.005), unlike SUVmax. Patients with a high ESSDAI score had a higher PET/CT activity score than patients with a low ESSDAI score (3 vs 1, p=0.004). PET was also correlated with gammaglobulin levels (r=0.43, p=0.02), but not with the presence of cryoglobulinemia, activated complement or beta-2 microglobulin levels. The FDG uptake in patients with lymphoma (n=4) was higher than in patients without lymphoma (SUVmax=5.4 vs. 3.2, p=0.05). CONCLUSION: We described a new PET/CT activity score, which correlates to ESSDAI and could help to assess disease activity in SS patients. PET can also help in the diagnosis of lymphoma, even if inflammatory lymph nodes can be frequently observed in SS patients.

The rim sign: FDG-PET/CT pattern of pulmonary infarction.

OBJECTIVE: We aimed to describe a pattern of rim uptake observed in lung infarction on FDG-PET/CT, called the "rim sign." It was defined as a continuous slight FDG uptake along the border of a subpleural consolidation without uptake within the consolidation. METHODS: We retrospectively reviewed the FDG-PET/CT studies of 400 patients referred for thoracic oncological workup from November 2010 to July 2011. The rim sign was observed in six patients who had confirmed pulmonary infarction (PI) on MDCT showing acute pulmonary embolism (n = 4) or tumoral arterial obstruction (n = 2). RESULTS: Eight PIs in the six patients exhibited the rim sign with slight uptake (median SUV(max): 3.6, 2.2-6.8) and median size of 48.5 mm (30-74). On MDCT, central lucencies, triangular shape and vessel sign were observed in 5/8, 4/8 and 1/8 cases, respectively. Two out of the eight PIs exhibited only the rim sign and none the suggestive MDCT sign. CONCLUSION: The rim sign is easily recognisable at FDG-PET/CT and is strongly suggestive of PI. This pattern can be observed even in the absence of suggestive findings on MDCT. Recognition of this sign should prompt investigations for pulmonary embolism. MAIN MESSAGES: • The rim sign is a slight FDG uptake around an area of subpleural consolidation • The rim sign is strongly suggestive of pulmonary infarction • Recognition of the rim sign should prompt investigations for pulmonary embolism.

Diagnosis of synchronous isolated splenic metastasis from lung adenocarcinoma: complementary role of FDG PET/CT and diffusion-weighted MRI.

Isolated splenic metastasis is extremely rare. In this study, we report a case of a 52-year-old man referred for Pancoast Tobias Syndrome by which FDG PET/CT detected an isolated splenic metastasis. Diffusion-weighted MRI confirmed the isolated splenic lesion. A low apparent diffusion coefficient was consistent with a tumor lesion. CT-guided biopsy of both the lesions and histopathologic findings confirmed a lung adenocarcinoma with an isolated splenic metastasis. This case reveals a very rare occurrence of isolated splenic metastases in the context of lung cancer and illustrates the role of multimodality functional imaging for the early detection of uncommon metastasis.

Tracheobronchial FDG uptake in primary amyloidosis detected by PET/CT.

Tracheobronchial amyloidosis is a rare manifestation of the disease and has never been described with FDG PET/CT. In this study, we report a case of a 70-year-old man with increasing dyspnea, a right pleural effusion, a tracheobronchial circumferential wall thickening, and a mediastinal fat infiltration on CT scan. FDG PET/CT revealed intense tracheobronchial uptake associated with mediastinal and intra-abdominal fat uptake. Bronchoscopy and mediastinoscopy with biopsies confirmed the diagnosis of primary amyloidosis and excluded malignancy. FDG PET/CT could be useful for the evaluation of tracheobronchial amyloidosis metabolic activity and follow-up.

Visualization of amyloid arthropathy in light-chain systemic amyloidosis on F-18 FDG PET/CT scan.

We report a case of 63-year-old man with symmetrical joint swelling of the interphalangeal and metacarpal joints, associated with isolated hypogammaglobulinemia. Accessory glands biopsy revealed the presence of amyloidal deposits. PET/CT showed increased F-18 FDG activity in thickened soft tissues corresponding to amyloid arthropathy. Like multiple myeloma, PET/CT could be an interesting imaging in light-chain amyloidosis.