Antonella Stefanelli

MIBG scintigraphy in differential diagnosis of Parkinsonism: a meta-analysis

ObjectiveDifferential diagnosis between Parkinson’s disease (PD) and other Parkinsonism using clinical criteria or imaging methods is often difficult. The purpose of this study is to systematically review and meta-analyze published data about the diagnostic performance of myocardial innervation imaging using 123I-metaiodobenzylguanidine (MIBG) scintigraphy in differential diagnosis between PD and other Parkinsonism.MethodsA comprehensive computer literature search of studies published through March 2011 regarding MIBG scintigraphy in patients with PD and other Parkinsonism was performed in PubMed/MEDLINE and Embase databases. Only studies in which MIBG scintigraphy was performed for differential diagnosis between PD and other Parkinsonism were selected. Pooled sensitivity, pooled specificity and area under the ROC curve were calculated to measure the accuracy of MIBG scintigraphy in differential diagnosis between PD and other Parkinsonism.ResultsNineteen studies comprising 1,972 patients (1,076 patients with PD, 117 patients with other Lewy body diseases and 779 patients with other diseases) were included in this meta-analysis. The pooled sensitivity of MIBG scintigraphy in detecting PD was 88% (95% CI 86–90%); the pooled specificity of MIBG scintigraphy in discriminating between PD and other Parkinsonism was 85% (95% CI 81–88%). The area under the ROC curve was 0.93.ConclusionsIn patients with clinically suspected PD, myocardial innervation imaging demonstrated high sensitivity and specificity. MIBG scintigraphy is an accurate test in this setting. Nevertheless, possible causes of false-negative and false-positive results should be kept in mind when interpreting the scintigraphic results.

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.

18F-Fluorodeoxyglucose positron emission tomography in evaluating treatment response to imatinib or other drugs in gastrointestinal stromal tumors: a systematic review☆

OBJECTIVE To systematically review the role of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) in evaluating treatment response to imatinib or other drugs in gastrointestinal stromal tumors (GIST). METHODS A comprehensive literature search of published studies through February 2011 in PubMed/MEDLINE and EMBASE databases was performed. RESULTS We identified 19 studies including 628 patients with GIST. Main findings of included studies are presented. CONCLUSIONS (18)F-FDG PET has a significant value in assessing treatment response to imatinib or other drugs in GIST patients. (18)F-FDG PET allows an early assessment of treatment response and is a strong predictor of clinical outcome.

Diagnostic performance of iodine-123-metaiodobenzylguanidine scintigraphy in differential diagnosis between Parkinson's disease and multiple-system atrophy: A systematic review and a meta-analysis

BACKGROUND AND PURPOSE This study was designed to review the diagnostic performance of iodine-123-metaiodobenzylguanidine (MIBG) scintigraphy in differential diagnosis between Parkinsons disease (PD) and multiple-system atrophy (MSA). METHODS A comprehensive computer literature search of studies published through March 2011 regarding MIBG scintigraphy in patients with PD and MSA was performed in PubMed/MEDLINE and Embase databases. Only studies in which MIBG scintigraphy was performed for differential diagnosis between PD and MSA were selected. Pooled sensitivity and specificity of MIBG scintigraphy were presented with a 95% confidence interval (CI). The area under the ROC curve was calculated to measure the accuracy of MIBG scintigraphy in differential diagnosis between PD and MSA. RESULTS Ultimately, we identified 12 studies comprising a total of 1226 patients (593 patients with PD, 117 patients with other Lewy body disease, 129 patients with MSA, and 387 patients with other diseases). The pooled sensitivity of MIBG scintigraphy to detect PD was 89% (95% CI: 86-91%); the pooled specificity of MIBG scintigraphy to discriminate between PD and MSA was 77% (95% CI: 68-84%). The area under the ROC curve was 0.93. CONCLUSIONS MIBG scintigraphy is an accurate test for PD detection and differential diagnosis between PD and MSA; this method shows high sensitivity and adequate specificity in this field. Nevertheless, possible causes of false negative and false positive findings should be considered when interpreting the scintigraphic results.

Multicenter comparison of 18F-FDG and 68Ga-DOTA-peptide PET/CT for pulmonary carcinoid

Purpose The aims of this study were to retrospectively evaluate and compare the detection rate (DR) of 68Ga-DOTA-peptide and 18F-FDG PET/CT in the preoperative workup of patients with pulmonary carcinoid (PC) and to assess the utility of various functional indices obtained with the 2 tracers in predicting the histological characterization of PC, that is, typical versus atypical. Methods Thirty-three consecutive patients with confirmed PC referred for 18F-FDG and 68Ga-DOTA-peptide PET/CT in 2 centers between January 2009 and April 2013 were included. The semiquantitative evaluation included the SUVmax, the SUV of the tumor relative to the maximal liver uptake for 18F-FDG (SUVT/L) or the maximal spleen uptake for 68Ga-DOTA-peptides (SUVT/S), the ratio between SUVmax of 68Ga-DOTA-peptides PET/CT, and the SUVmax of 18F-FDG PET/CT (SUVmax ratio). Histology was used as reference standard. Results Definitive diagnosis consisted of 23 typical carcinoids (TCs) and 10 atypical carcinoids. 18F-FDG PET/CT was positive in 18 cases and negative in 15 (55% DR). 68Ga-DOTA-peptide PET/CT was positive in 26 cases and negative in 7 (79% DR). In the subgroup analysis, 68Ga-DOTA-peptide PET/CT was superior in detecting TC (91% DR; P < 0.001), whereas 18F-FDG PET/CT was superior in detecting atypical carcinoid (100% DR; P = 0.04). The SUVmax ratio was the most accurate semiquantitative index in identifying TC. Conclusions Overall diagnostic performance of PET/CT in detecting PC is optimal when integrating 18F-FDG and 68Ga-DOTA-peptide PET/CT findings. In the subgroup analysis, the SUVmax ratio seems to be the most accurate index in predicting TC. Both methods should be performed when PC is suspected or when the histological subtype is undefined.

Usefulness of F-18 FDG PET/CT in the follow-up of POEMS syndrome after autologous peripheral blood stem cell transplantation

We report a case of a patient with relapse of POEMS syndrome (peripheral neuropathy, organomegaly, endocrinopathy, monoclonal plasma proliferative disorder, skin changes) that occurred 6 years after an autologous peripheral blood stem cell transplantation. F-18 FDG PET/CT showed several hypermetabolic as well as nonhypermetabolic bone lesions. Based on these findings, the patient was referred for radiotherapy to the hypermetabolic bone lesions. After autologous peripheral blood stem cell transplantation, F-18 FDG PET/CT may play a pivotal role in detecting new bone lesions in patients with POEMS syndrome, which may be treated by a focalized radiotherapy and/or systemic therapy.

F-FDG PET Imaging in the Evaluation of Treatment Response to New Chemotherapies beyond Imatinib for Patients with Gastrointestinal Stromal Tumors

Aim. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) is a powerful tool for staging and defining “good responders” to chemotherapy in tumor setting. Gastrointestinal stromal tumors (GISTs) are sarcoma involving gastrointestinal tract and may require a chemotherapy including imatinib, a tyrosine kinase inhibitor agent. Some GIST patients become refractory to imatinib; therefore, other tyrosine kinase inhibitors or concomitant chemotherapy may be considered for treatment. The aim of this paper is to assess if 18F-FDG PET imaging is a useful tool to evaluate treatment response to new chemotherapies beyond imatinib for GIST patients. Methods. We performed a review of the literature about the role of 18F-FDG PET in the evaluation of treatment response to new chemotherapies beyond imatinib for GIST patients. Results and Conclusions. 18F-FDG PET seems to be able to assess therapy response earlier than computed tomography (CT) imaging in imatinib refractory GIST patients treated with other agents. However, a dual modality PET-CT imaging is recommendable to achieve a better detection of all lesions.

Multifocal Extra-Adrenal Paraganglioma Evaluated With Different PET Tracers: Comparison Between 18F-FDG, 18F-DOPA and 68Ga DOTANOC PET/CT

A 40-year-old female patient with suspected multifocal extra-adrenal paraganglioma, on the basis of biochemical, genetic, and conventional imaging data, underwent 18F-FDG, 18F-DOPA and 68Ga DOTANOC PET/CT. FDOPA- and FDG-PET/CT detected a multifocal mediastinal and cervical paraganglioma. 68Ga-DOTANOC PET/CT detected 2 additional lesions compared to the other PET/CT methods. In our case, somatostatin receptor PET/CT with 68Ga-DOTANOC correctly assessed the extent of the disease in a patient with multifocal paraganglioma.

Masking effect of chronic pancreatitis in the interpretation of somatostatin receptor positron emission tomography in pancreatic neuroendocrine tumors.

To the Editor: W e present the rare occurrence of a concurrent pancreatic neuroendocrine tumor (pNET) and pancreatic ductal adenocarcinoma (PDAC) in a patient with multiple endocrine neoplasia 1 (MEN1) syndrome. It is important for clinicians to consider the possibility of PDAC in patients with MEN1 because aggressive early surgical intervention provides the only chance of cure. Multiple endocrine neoplasia 1 is characterized by parathyroid adenomas, pNETs, and anterior pituitary tumors. Multiple endocrine neoplasia 1Yassociated pNETs are usually slowly progressive and associated with low malignant potential. In the context of MEN1, pancreatic NET size correlates with prognosis and the presence of metastases,2 and lesions of more than 2 cm are associated with greater genetic instability and malignant behaviour. The European Neuroendocrine Tumour Society recommendations for management of pancreatic lesions in a patient with MEN1 state that early diagnosis and surgical excision of MEN1-related pNET improve survival, preventing or delaying the development of distant metastases.4 It is mandatory to operate on MEN1-related nonfunctioning pancreatic tumors with metastases, size of more than 2 cm, or yearly increased size of more than 0.5 cm. Management of pNETs of less than 2 cm is controversial, current recommendation being intensive surveillance to avoid repeated intervention where lesions are typically multiple and behave in an indolent fashion.

123I-MIBG Scintigraphy as a Powerful Tool to Plan an Implantable Cardioverter Defibrillator and to Assess Cardiac Resynchronization Therapy in Heart Failure Patients

Iodine-123-metaiodobenzylguanidine (123I-MIBG) scintigraphy is a nuclear medicine technique which describes the functional status of the cardiac sympathetic nervous system. It is well known that an autonomic dysfunction is present in heart failure setting as a neuronal uptake of norepinephrine is impaired in the failing myocardium. Reduction in sympathetic nervous function in the heart, measured by reduced myocardial uptake of 123I-MIBG, is an indicator of poor prognosis for heart failure patients. The aim of this paper was to investigate the role of 123I-MIBG scintigraphy in evaluating the need of implantable cardioverter defibrillator (ICD) and the response to cardiac resynchronization therapy (CRT) in heart failure patients. For this purpose scientific literature data on these topics were reviewed. Based on literature data, 123I-MIBG scintigraphy seems to be a useful tool to assess which patients may benefit most from an ICD implantation to reduce the risk of ventricular arrhythmia or sudden cardiac death. Furthermore, 123I-MIBG scintigraphy seems to predict which patients will response to CRT with an improvement in left ventricular function.