Metastasis From Clear Cell Renal Cell Carcinoma Mimicking Well-Differentiated Pancreatic Neuroendocrine Tumor at 18F-FDG and 68Ga-DOTATOC PET/CT.

ABSTRACT: Dual-tracer PET/CT with both 18F-FDG and 68Ga-DOTA-conjugated peptides is currently used in clinical routine for characterizing pNET (pancreatic masses suspicious for neuroendocrine tumor). We describe here the case of a 81-year-old man with a pancreatic lesion showing high 68Ga-DOTATOC uptake and mild 18F-FDG avidity, thus suggesting a well-differentiated pNET, which resulted at endoscopic ultrasound-guided fine-needle aspiration to be a clear cell renal cell carcinoma metastasis. In fact, the patient had right nephrectomy for clear cell renal cell carcinoma 27 years earlier. This case puts light on the role of PET/CT with 68Ga-DOTATOC in imaging RCC, a field which deserves to be further explored.

DRAW.IN.G.: A tool to explore children's representation of the preschool environment.

The use of drawing as a research tool has often been the subject of debate in the field of developmental psychology, especially for the exploration of children's meanings on a specific topic. Methodological limitations do emerge when using drawing in research, especially in preschool age. One of the main critical aspects concerns the lack of systematic and standardized coding methods that include clear and operationalizable categories to analyze the content of the drawings, and that associate a brief interview with the children aimed at avoiding misinterpretations. To bridge this gap, the present contribution introduces a new methodological tool named DRAW.IN.G. (DRAWing and Interview Grid), consisting of a specific procedure and a coding system that allow for a systematic investigation of implicit and explicit levels of children's representation emerging via drawings and interviews. The specific topic investigated by DRAW.IN.G. is children's representation of the preschool environment; the scarcity of studies on this issue, despite the importance of including children's point of view in the design processes of educational spaces makes the tool particularly current and relevant to fill some gaps in research in the educational field. The DRAW.IN.G. coding system, developed on the basis of existing literature on the analysis of drawings, includes five main dimensions of children's representation of the educational environment: physical, behavioral, relational, emotional and motivational dimensions, articulated in 18 macro-categories and 90 categories that make up the scoring grid. To assess the validity of the method, a first application was conducted with a sample of 262 children (141 males, 121 females; mean age = 55.78 months; SD = 11.10; range 37-77 months) from five Italian preschools. Categorical inter-rater reliability of two independent raters showed good to excellent agreement for the categories of the grid, indicating their appropriateness and clarity. The validation study indicated the potential of the method, also revealing some critical aspects to be considered. Both methodological and practical implications are discussed.

Detection of Unilateral Axillary Nodal Uptake Both at 68Ga-DOTATOC and 18F-FDG PET/CT After 1 Week From COVID-19 Vaccine.

ABSTRACT: Recently, vaccination against COVID-19 has gained wide diffusion, especially among vulnerable individuals, such as cancer patients. At the same time, patients have been undergoing PET/CT examinations after vaccination in an increasing number, and cases of false-positive axillary nodal uptake have been described, mostly at 18F-FDG PET. Here, we describe the case of both 68Ga-DOTATOC and 18F-FDG axillary nodal uptake in a young woman affected by a metastatic retroperitoneal paraganglioma.

Brain Stem Glucose Hypermetabolism in Amyotrophic Lateral Sclerosis/Frontotemporal Dementia and Shortened Survival: An 18F-FDG PET/MRI Study.

A few 18F-FDG PET/CT studies have revealed the presence of brain hypermetabolism in the brain stem and cervical spinal cord of patients within the amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) continuum. We aimed to investigate this finding through a hybrid PET/MRI system, allowing a more precise depiction of the spatial pattern of metabolic changes in the brain stem and cervical spinal cord. Methods: Twenty-eight patients with a diagnosis of ALS or a diagnosis of the behavioral variant of FTD plus motoneuron disease, as well as 13 control subjects, underwent 18F-FDG PET/MRI. Mean normalized 18F-FDG uptake in the midbrain/pons, medulla oblongata, and cervical spinal cord as defined on the individual's MRI scans were compared between groups. Furthermore, the associations between regional 18F-FDG uptake and clinical and demographic characteristics-including gene mutation, type of onset (bulbar, spinal, dementia), and clinical characteristics-were investigated. Results: A significant (P < 0.005) increment in glucose metabolism in the midbrain/pons and medulla oblongata was found in ALS/FTD patients (spinal-ALS and FTD-motor neuron disease subgroups) in comparison to controls. No relevant associations between clinical and metabolic features were reported, although medulla oblongata hypermetabolism was associated with shortened survival (P < 0.001). Conclusion: Increased glucose metabolism in the brain stem might be due to neuroinflammation, one of the key steps in the pathogenic cascade that leads to neurodegeneration in ALS/FTD. 18F-FDG PET/MRI could be a valuable tool to assess glial changes in the ALS/FTD spectrum and could serve as a prognostic biomarker. Large prospective initiatives would likely shed more light on the promising application of PET/MRI in this setting.

PET/MR in recurrent glioblastoma patients treated with regorafenib: [18F]FET and DWI-ADC for response assessment and survival prediction.

OBJECTIVE: The use of regorafenib in recurrent glioblastoma patients has been recently approved by the Italian Medicines Agency (AIFA) and added to the National Comprehensive Cancer Network (NCCN) 2020 guidelines as a preferred regimen. Given its complex effects at the molecular level, the most appropriate imaging tools to assess early response to treatment is still a matter of debate. Diffusion-weighted imaging and O-(2-18F-fluoroethyl)-L-tyrosine positron emission tomography ([18F]FET PET) are promising methodologies providing additional information to the currently used RANO criteria. The aim of this study was to evaluate the variations in diffusion-weighted imaging/apparent diffusion coefficient (ADC) and [18F]FET PET-derived parameters in patients who underwent PET/MR at both baseline and after starting regorafenib. METHODS: We retrospectively reviewed 16 consecutive GBM patients who underwent [18F]FET PET/MR before and after two cycles of regorafenib. Patients were sorted into stable (SD) or progressive disease (PD) categories in accordance with RANO criteria. We were also able to analyze four SD patients who underwent a third PET/MR after another four cycles of regorafenib. [18F]FET uptake greater than 1.6 times the mean background activity was used to define an area to be superimposed on an ADC map at baseline and after treatment. Several metrics were then derived and compared. Log-rank test was applied for overall survival analysis. RESULTS: Percentage difference in FET volumes correlates with the corresponding percentage difference in ADC (R = 0.54). Patients with a twofold increase in FET after regorafenib showed a significantly higher increase in ADC pathological volume than the remaining subjects (p = 0.0023). Kaplan-Meier analysis, performed to compare the performance in overall survival prediction, revealed that the percentage variations of FET- and ADC-derived metrics performed at least as well as RANO criteria (p = 0.02, p = 0.024 and p = 0.04 respectively) and in some cases even better. TBR Max and TBR mean are not able to accurately predict overall survival. CONCLUSION: In recurrent glioblastoma patients treated with regorafenib, [18F]FET and ADC metrics, are able to predict overall survival and being obtained from completely different measures as compared to RANO, could serve as semi-quantitative independent biomarkers of response to treatment. ADVANCES IN KNOWLEDGE: Simultaneous evaluation of [18F]FET and ADC metrics using PET/MR allows an early and reliable identification of response to treatment and predict overall survival.