Maria Vittoria Mattoli

Usefulness of whole-body fluorine-18-fluorodeoxyglucose positron emission tomography in patients with large-vessel vasculitis: a systematic review

The objective of this study is to systematically review the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) with fluorine-18-fluorodeoxyglucose (FDG) in patients with large-vessel vasculitis (LVV). A comprehensive literature search of published studies through April 2011 in PubMed/MEDLINE and Scopus databases regarding whole-body FDG-PET and PET/CT in patients with LVV was performed. We identified 32 studies including 604 LVV patients. The main findings of these studies are presented. The conclusions are the following: (1) FDG-PET and PET/CT are useful imaging methods in the initial diagnosis and in the assessment of activity and extent of disease in patients with LVV; (2) the correlation between FDG-PET findings and serological levels of inflammatory markers, as well as the usefulness of FDG-PET and PET/CT in evaluating treatment response, remains unclear; (3) it appears that there is a superiority of FDG-PET and PET/CT over conventional imaging methods in the diagnosis of LVV, but not in assessing disease activity under immunosuppressive treatment, in predicting relapse or in evaluating vascular complications; and (4) given the heterogeneity between studies with regard to PET analysis and diagnostic criteria, a standardization of the technique is needed.

Diagnostic accuracy of ¹⁸F-FDG-PET and PET/CT in patients with Ewing sarcoma family tumours: a systematic review and a meta-analysis.

ObjectiveTo systematically review and meta-analyse literature data on the diagnostic performance of fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography (PET) and positron emission tomography/computed tomography (PET/CT) in patients with Ewing sarcoma family tumours (ESFT).Materials and methodsPubMed/MEDLINE, Embase and Scopus databases were searched for articles that evaluated FDG-PET and PET/CT in patients with ESFT from inception to 31 May 2011. Studies that fulfilled the three following criteria were included in the systematic review: FDG-PET or PET/CT performed in patients with ESFT; articles about the diagnostic accuracy of FDG-PET and PET/CT; sample size of at least 10 patients with ESFT were included. Studies in which there were sufficient data to reassess sensitivity and specificity of FDG-PET or PET/CT in ESFT were included in the meta-analysis, excluding duplicate publications. Finally, pooled sensitivity, pooled specificity and area under the receiver operating characteristic (ROC) curve of FDG-PET or PET/CT in ESFT were calculated.ResultsWe found 13 studies comprising a total of 342 patients with ESFT. The main findings of the studies included are presented. The meta-analysis of five selected studies provided these results about FDG-PET and PET/CT in ESFT: pooled sensitivity: 96% (95% confidence interval [CI] 91–99%); pooled specificity: 92% (95% CI 87–96%); area under the ROC curve: 0.97.ConclusionWith regard to the staging and restaging of patients with ESFT, the sensitivity, specificity and accuracy of FDG-PET and PET/CT are high; the combination of FDG-PET or PET/CT with conventional imaging is a valuable tool for the staging and restaging of ESFT and has a relevant impact on the treatment strategy plan.

The role of Fluorine-18-Fluorodeoxyglucose positron emission tomography in staging and restaging of patients with osteosarcoma.

Background. The objective of this study is to systematically review the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) with Fluorine-18-Fluorodeoxyglucose (FDG) in patients with osteosarcoma (OS). Methods. A comprehensive literature search of published studies through October 10th, 2012 in PubMed/MEDLINE, Embase and Scopus databases regarding whole-body FDG-PET and FDG-PET/CT in patients with OS was performed. Results. We identified 13 studies including 289 patients with OS. With regard to the staging and restaging of OS, the diagnostic performance of FDG-PET and PET/CT seem to be high; FDG-PET and PET/CT seem to be superior to bone scintigraphy and conventional imaging methods in detecting bone metastases; conversely, spiral CT seems to be superior to FDG-PET in detecting pulmonary metastases from OS Conclusions. Metabolic imaging may provide additional information in the evaluation of OS patients. The combination of FDG-PET or FDG-PET/CT with conventional imaging methods seems to be a valuable tool in the staging and restaging of OS and may have a relevant impact on the treatment planning.

Emerging role of Fluorine-18-fluorodeoxyglucose positron emission tomography in patients with retroperitoneal fibrosis: a systematic review

To systematically review the literature data on the role of Fluorine-18-fluorodeoxyglucose positron emission tomography and positron emission tomography/computed tomography (FDG-PET and PET/CT) in patients with retroperitoneal fibrosis (RF), PubMed/MEDLINE, Embase and Scopus databases were searched for articles that evaluated the usefulness of FDG-PET and PET/CT in patients with RF from inception to March 31, 2012. Review articles or editorials, articles not in the field of interest of this review, case reports and preclinical studies were excluded. Only studies including FDG-PET or PET/CT scans performed in at least three patients with RF were included. Ten studies comprising a total of 101 patients with RF were found. The main findings of the included studies are described. FDG-PET and PET/CT are feasible and suitable imaging methods for evaluating patients with RF. These functional imaging techniques seem to be useful both in the diagnosis (mainly in the assessment of activity and extent of the disease) and in evaluating the treatment response in patients with RF. Given the heterogeneity among the various studies for PET analysis and diagnostic criteria, a standardization of the technique is required in order to achieve reproducible and inter-observer independent results. Moreover, further studies are needed to substantiate the role of FDG-PET and PET/CT in patients with RF.

Diagnostic Performance of 18F-Fluorodeoxyglucose in 162 Small Pulmonary Nodules Incidentally Detected in Subjects Without a History of Malignancy

BACKGROUND Solitary pulmonary nodule (SPN) still represents a diagnostic challenge. The aim of our study was to evaluate the diagnostic performance of (18)F-fluorodeoxyglucose positron emission tomography-computed tomography in one of the largest samples of small SPNs, incidentally detected in subjects without a history of malignancy (nonscreening population) and undetermined at computed tomography. METHODS One-hundred and sixty-two small (>0.8 to 1.5 cm) and, for comparison, 206 large nodules (>1.5 to 3 cm) were retrospectively evaluated. Diagnostic performance of (18)F-fluorodeoxyglucose visual analysis, receiver-operating characteristic (ROC) analysis for maximum standardized uptake value (SUVmax), and Bayesian analysis were assessed using histology or radiological follow-up as a golden standard. RESULTS In 162 small nodules, (18)F-fluorodeoxyglucose visual and ROC analyses (SUVmax = 1.3) provided 72.6% and 77.4% sensitivity and 88.0% and 82.0% specificity, respectively. The prevalence of malignancy was 38%; Bayesian analysis provided 78.8% positive and 16.0% negative posttest probabilities of malignancy. In 206 large nodules (18)F-fluorodeoxyglucose visual and ROC analyses (SUVmax = 1.9) provided 89.5% and 85.1% sensitivity and 70.8% and 79.2% specificity, respectively. The prevalence of malignancy was 65%; Bayesian analysis provided 85.0% positive and 21.6% negative posttest probabilities of malignancy. In both groups, malignant nodules had a significant higher SUVmax (p < 0.0001) than benign nodules. Only in the small group, malignant nodules were significantly larger (p = 0.0054) than benign ones. CONCLUSIONS (18)F-fluorodeoxyglucose can be clinically relevant to rule in and rule out malignancy in undetermined small SPNs, incidentally detected in nonscreening population with intermediate pretest probability of malignancy, as well as in larger ones. Visual analysis can be considered an optimal diagnostic criterion, adequately detecting a wide range of malignant nodules with different metabolic activity.

Physiological Activity of Spinal Cord in Children: An 18F-FDG PET-CT Study

Study Design. Retrospective study. Objective. To evaluate, in a pediatric population, 18F-Fluoro-deoxy-glucose (18F-FDG) metabolic activity of normal spinal cord and to assess the correlation with demographic, clinical, and environmental variables. Summary of Background Data. 18F-FDG uptake of normal spinal cord is variable in children. The knowledge of physiological metabolism of spinal cord is essential to distinguish normal from pathological findings by positron emission tomography–computed tomography (PET-CT). Methods. We retrospectively evaluated 18F-FDG positron emission tomography–computed tomography scans from a total of 167 pediatric patients (97 males; 3.9–18.9 yr) divided into 4 age groups (0–4.9 yr, 5–9.9 yr, 10–14.9 yr, and 15–18.9 yr), excluding those submitted to previous or recent therapeutic procedures influencing spinal cord metabolism or with central nervous system diseases. Spinal cord was divided into 3 levels (C1–C7; D1–D6; and D7–L1), and maximum standardized uptake value (SUVmax) of each cord level was measured. Correlations between SUVmax and spinal cord level, age, body weight, sex, type of disease, and season were statistically assessed. Results. Median SUVmax was similar and significantly (P < 0.01) higher at C1–C7 and D7–L1 levels than at D1–D6 level and it significantly (P < 0.01) increased with age in all spinal cord levels. A positive and significant association between SUVmax and body weight, female sex, and Hodgkin lymphoma was found. No significant association with season was observed. By multivariate analysis, only weight and female sex remained significant. Conclusion. Knowledge of physiological 18F-FDG spinal cord activity in children is essential for a correct interpretation of positron emission tomography–computed tomography, especially in oncologic pediatric patients to avoid potential pitfalls. Level of Evidence: N/A

Intranasal Nerve Growth Factor administration improves cerebral functions in a child with severe traumatic brain injury: A case report

ABSTRACT Background: Nerve growth factor (NGF) promotes neural recovery after experimental traumatic brain injury (TBI) supporting neuronal growth, differentiation and survival of brain cells and up-regulating the neurogenesis-associated protein Doublecortin (DCX). Only a few studies reported NGF administration in paediatric patients with severe TBI. Methods: A four-year-old boy in a persistent unresponsive wakefulness syndrome (UWS) was treated with intranasal murine NGF administration 6 months after severe TBI. The patient received four cycles of intranasal NGF (0.1 mg/kg, twice a day for 10 consecutive days). Results: NGF administration improved functional [Positron Emission Tomography/Computed Tomography (PET/CT); Single photon emission/Computed Tomography (SPECT/CT) and Magnetic Resonance Imaging (MRI)] assessment, electrophysiological [Electroencephalogram (EEG) and Visual Evoked Potential (VEP)] studies and clinical conditions. He showed improvements in voluntary movements, facial mimicry, phonation, attention and verbal comprehension, ability to cry, cough reflex, oral motility, feeding capacity, and bowel and urinary functions. After NGF administration, raised levels of both NGF and DCX were found in the cerebrospinal fluid of the patient. No side effects were reported. Conclusions: Although further studies are needed for better understanding the neuroprotective role of this neurotrophin, intranasal NGF administration appears to be a promising and safe rescuing strategy treatment in children with neurological impairment after TBI.

Fluorine-18-Fluorodeoxyglucose Positron Emission Tomography in Assessing Retroperitoneal Fibrosis: A Literature Review

Background and Purpose. Several studies have evaluated the role of fluorine-18-fluorodeoxyglucose positron emission tomography and positron emission tomography/computed tomography (FDG-PET and PET/CT) in diagnosing and assessing disease activity in patients with retroperitoneal fibrosis (RF). The aim of our paper is to perform a literature review on this topic. Methods. Scientific articles that evaluated the usefulness of FDG-PET and PET/CT in patients with RF were searched and discussed. Results. Eleven studies were found, and the main findings of these articles were described. Conclusion. FDG-PET and PET/CT are useful functional imaging methods for assessing patients with RF both in the diagnosis and in the treatment response evaluation. Moreover, further studies are needed to substantiate the role of FDG-PET and PET/CT in patients with RF.

Recurrent renal hyperparathyroidism due to parathyromatosis

Parathyromatosis is the most severe type of recurrent secondary hyperparathyroidism (SHPT) after parathyroidectomy (PTX) in haemodialysis patients. It is difficult to completely remove all foci of parathyroid tissue and neck re-explorations are often required. Here, we report for the first time a case of recurrent SHPT due to parathyromatosis treated by radio-guided PTX. A haemodialysed 48-year-old woman with recurrent SHPT due to parathyromatosis was treated by radio-guided PTX. Preoperatively Ultrasonography, 99Tc-SestaMIBI scintigraphy and magnetic resonances of the neck and thorax were performed. The preoperative imaging techniques detected four parathyroid nodules, while intraoperative gamma probe identified six nodules (three in atypical site). No frozen sections were performed during surgery. Post-operative intact parathyroid hormone levels were stabilized in the range 300–500 pg/mL during the 26 month follow-up by means of cinacalcet and paricalcitol therapy. In cases of parathyromatosis, the preoperative imaging techniques are inadequate, while intraoperative gamma probe is useful to detect the parathyroid tissue and allows a more extensive cytoreduction because it ensures the removal of undetectable and ectopic parathyroid foci. The operative time is reduced and frozen sections are unnecessary. However, the radio-guided PTX do not rule out parathyromatosis recurrence and complementary medical treatment is appropriate.

Usefulness of 11C-Methionine Positron Emission Tomography in Differential Diagnosis between Recurrent Tumours and Radiation Necro-sis in Patients with Glioma: An Overview

Differential diagnosis between radiation necrosis and tumour recurrence is important in the clinical manage- ment of patients with glioma. We performed an overview of the literature in order to summarize the role of 11 C- methionine positron emission tomography (MET-PET) in this setting. This functional imaging method appears to have a high sensitivity, specificity, and accuracy in differentiating between glioma recurrence and radiation necrosis. Neverthe- less, possible false negative and false positive results of MET-PET should be well kept in mind in the management of pa- tients with glioma.