[Show abstract][Hide abstract] ABSTRACT: Positron emission tomography-computed tomography (PET-CT) with (18)F-fluorodeoxyglucose (FDG) has emerged as a rapidly evolving diagnostic tool for infectious diseases. However, the optimal imaging time in this clinical setting is not clear yet. The aim of this study is to investigate whether delayed (3 hours) FDG PET-CT could increase the diagnostic accuracy of this technique compared to standard (1 hour) imaging in the detection of septic foci involving the pocket and/or pacing leads in patients with suspected cardiovascular implantable electronic device (CIED) infection scheduled for device removal.
Twenty-seven patients underwent standard and delayed imaging. PET-CT results were compared to bacteriological cultures after CIED removal. Fifteen controls free of infection underwent PET-CT imaging as part of investigation of malignancy. The diagnostic accuracy of delayed imaging was significantly higher than 1-hour scan for lead infection (70% vs 51%, P = .024). No significant difference was found between standard and delayed diagnostic accuracy for pocket or device infection. Semi-quantitative analysis showed that mean pocket and lead target-to-background ratio were significantly higher on delayed compared to standard imaging (3.7 ± 1.9 vs 1.6 ± 1.1, P = .0002; 3.0 ± 1.3 vs 0.7 ± 1.0, P = .01).
Delayed FDG PET-CT imaging should be considered at least in patients with negative 1-hour scan and founded suspicion of pacing lead infection.
[Show abstract][Hide abstract] ABSTRACT: To evaluate whether standardized uptake value (SUV) and/or metabolic rate of glucose (MRglu) are different among epithelioid, mixed, and spindle cell uveal melanomas, as well as between low and high risk melanomas; to correlate ultrasonographic data and metabolic parameters with histopathological features; and to assess the role of (18)F-FDG PET/CT for evaluating prognosis.
Of 34 eligible patients prospectively enrolled with clinical suspicion of medium/large uveal melanoma, 26 (15 men, mean age 62.8 ± 11.8 years) were evaluated. All patients underwent metastatic work-up, 3-D dynamic brain and whole-body (18)F-FDG PET/CT, and surgery.
Of the 26 ocular lesions, 23 showed (18)F-FDG uptake, with a sensitivity of 88 %. MRglu was significantly higher in the epithelioid cell melanomas than in the spindle cell melanomas, as well as in high-risk lesions than in low-risk lesions (p = 0.01, p = 0.02, respectively). SUV and MRglu were correlated with histopathological features while ultrasonographic data were not.
MRglu is useful for distinguishing the different cell types in uveal melanoma, as well as high-risk from low-risk lesions, while SUV is not. MRglu provides a more accurate evaluation of glucose consumption, whereas SUV provides only an estimation. In addition, the metabolic parameters correlate with histopathological features, well also reflecting cellular behaviour in ocular malignancy. A longer follow-up is needed to assess the role of (18)F-FDG in evaluating prognosis.
European Journal of Nuclear Medicine 07/2013; 40(11). DOI:10.1007/s00259-013-2488-6 · 5.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose:
We prospectively evaluated the regional cerebral metabolic rate of glucose (CMRglu) before and after ventricular shunt placement in idiopathic normal-pressure hydrocephalus (iNPH) patients, to investigate whether some brain regions are more involved than others; we also correlated the individual variations of CMRglu with the clinical scale score assessment after shunting.
Twenty iNPH patients (12 men; mean age 73 ± 9 years) underwent clinical scale score assessment and F-FDG PET-CT before and 1 week after shunting.
Before shunting, CMRglu values were similar in right and left brain regions, as well as after shunting. After shunting, 17 of 20 iNPH patients were clinically improved; all scale scores decreased, and CMRglu significantly increased in all regions (P < 10). In 3 of 20 iNPH patients, the symptoms persisted, the scale scores did not change, and CMRglu increased only in 3 regions: left frontal, left putamen, and right thalamus. Before shunting, no difference in global CMRglu between clinically improved (n = 17) and not improved (n = 3) iNPH patients was found. After shunting, a significant (P = 0.01) correlation between individual variations of CMRglu and clinical assessment was found.
These findings confirm that iNPH is a disease involving all cerebral regions almost in the same way, and shunt procedure has a similar effect on regional cerebral metabolism almost in the same way. Individual variations of CMRglu are more important than absolute values and correlate with clinical status after shunting. Clinical improvement depends not only on the capability to restore the cerebrospinal fluid dynamic, but also on the ability of cerebral parenchyma to recover the metabolic function.
Clinical nuclear medicine 05/2013; 38(6). DOI:10.1097/RLU.0b013e31828e949b · 3.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report an unusual case of malignant pseudothyroiditis (MPT) occurred in a 35-year-old female patient presenting with symptoms and signs of thyroiditis. Fine-needle aspiration biopsy of the thyroid demonstrated the presence of a MPT induced by a metastatic extrathyroidal carcinoma. F-FDG-PET/CT showed increased radiopharmaceutical uptake in the thyroid, in multiple cervical and mediastinal lymph nodes, and in a right pulmonary nodule. Histological examination demonstrated the presence of a metastatic non-small cell lung cancer (NSCLC). In this unusual case of MPT F-FDG-PET/CT has been useful in staging the disease and in detecting the primary tumor site.
Clinical nuclear medicine 03/2013; 39(2). DOI:10.1097/RLU.0b013e31827a27c8 · 3.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report a rare case of thymic Hodgkin lymphoma that occurred in an elderly patient and detected by F-FDG PET/CT. A 77-year-old woman with fever of unknown origin underwent F-FDG PET/CT scanning, which showed an area of increased radiopharmaceutical uptake in a mediastinal mass corresponding to a thymic lesion at CT scan. On the basis of the PET/CT findings, the patient was referred to surgery with the clinical suspicious of a thymoma. Histological examination demonstrated the presence of a primary thymic Hodgkin lymphoma instead.
Clinical nuclear medicine 01/2013; 38(5). DOI:10.1097/RLU.0b013e318252e01b · 3.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose:
Low-dose radiotherapy (LDR) (<50 cGy) induces enhanced cell killing in vitro via the hyper-radiation sensitivity phenomenon. Aim of this study was to evaluate the safety and efficacy of a palliative regimen combining pemetrexed and LDR (as a chemopotentiator) on patients affected by recurrent non-small-cell lung cancer (NSCLC).
Methods and materials:
Eligible patients had an ECOG performance status ≤2, one prior chemotherapy regimen for advanced NSCLC, adequate organ function, measurable lesions. Patients received pemetrexed (500 mg/m(2) IV) and concurrent LDR (40 cGy bid on days 1 and 2) delivered to target pulmonary or metastatic disease. This cycle was repeated fourfold every 21 days. The accrual was determined by the single proportion powered analysis (α=0.05, power=0.8) with H0 ("bad" response probability, 9% according to literature) and H1 ("good" response probability, 35% ongoing study); 19 is the number required.
Nineteen patients with stage III and IV disease were enrolled. Only one patient experienced neutropenia grade 4. All patients are evaluable for clinical response of irradiated lesion: overall response rate was 42%.
Low-dose radiotherapy combined with pemetrexed has a similar toxicity profile to chemotherapy alone. The response rate of this novel approach is encouraging, since it was higher than what was reported for pemetrexed alone (42% versus 9.1%). Additional scientific investigation of this new treatment paradigm is warranted.
Radiotherapy and Oncology 10/2012; 105(2). DOI:10.1016/j.radonc.2012.09.006 · 4.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objective:
The aim of our preliminary study was to evaluate the potential role of 18F-FDG PET-CT in monitoring response to reduced-intensity conditioning (RIC) transplant in a small series of chronic lymphocytic leukemia (CLL) patients and to compare the results with those obtained by standard criteria.
We retrospectively analyzed 9 consecutive refractory/relapsed CLL patients, who underwent RIC transplant from March 2004 until May 2009. PET-CT was planned at 6-8 months after transplant to assess response and at a mean of 6 months during follow-up. The mean long-term follow-up period was 38 months (range 12-74 months, median 29 months).
The first PET-CT showed abnormal 18F-FDG uptake in five patients, while by standard criteria eight patients showed persistent disease. At the end of follow-up (mean 38 months), all four patients with previously negative scan were still PET negative and in complete remission by standard criteria. All five patients with previously positive scan were still PET positive: one patient died for disease progression and four are alive with disease.
Our preliminary data, although in a small series of CLL patients, suggest that the metabolic findings revealed at first PET-CT after transplant seem to predict the patient outcome and to assess the metabolic disease status earlier than clinical evaluation by standard criteria. PET-CT performed during follow-up may be useful to early detect disease progression.
Annals of Nuclear Medicine 08/2012; 26(9). DOI:10.1007/s12149-012-0639-7 · 1.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To evaluate the metabolic changes on ¹⁸F-fluoro-2-deoxyglucose positron emission tomography integrated with computed tomography (¹⁸ F-FDG PET-CT) performed before, during and after concurrent chemo-radiotherapy in patients with locally advanced non-small cell lung cancer (NSCLC); to correlate the metabolic response with the delivered radiation dose and with the clinical outcome.
Twenty-five NSCLC patients candidates for concurrent chemo-radiotherapy underwent ¹⁸F-FDG PET-CT before treatment (pre-RT PET-CT), during the third week (during-RT PET-CT) of chemo-radiotherapy, and 4 weeks from the end of chemo-radiotherapy (post-RT PET-CT). The parameters evaluated were: the maximum standardized uptake value (SUVmax) of the primary tumor, the SUVmax of the lymph nodes, and the Metabolic Tumor Volume (MTV).
SUVmax of the tumor and MTV significantly (p=0.0001, p=0.002, respectively) decreased earlier during the third week of chemo-radiotherapy, with a further reduction 4 weeks from the end of treatment (p<0.0000, p<0.0002, respectively). SUVmax of lymph nodes showed a trend towards a reduction during chemo-radiotherapy (p=0.06) and decreased significantly (p=0.0006) at the end of treatment. There was a significant correlation (r=0.53, p=0.001) between SUVmax of the tumor measured at during-RT PET-CT and the total dose of radiotherapy reached at the moment of the scan. Disease progression free survival was significantly (p=0.01) longer in patients with complete metabolic response measured at post-RT PET-CT.
In patients with locally advanced NSCLC, ¹⁸F-FDG PET-CT performed during and after treatment allows early metabolic modifications to be detected, and for this SUVmax is the more sensitive parameter. Further studies are needed to investigate the correlation between the metabolic modifications during therapy and the clinical outcome in order to optimize the therapeutic strategy. Since the metabolic activity during chemo-radiotherapy correlates with the cumulative dose of fractionated radiotherapy delivered at the moment of the scan, special attention should be paid to methodological aspects, such as the radiation dose reached at the time of PET.
[Show abstract][Hide abstract] ABSTRACT: The objective of this study was to assess striatal dopamine transporter availability in patients with advanced Parkinson's disease (PD) before and after 13 months of unilateral extradural motor cortex stimulation (EMCS) with [123I]N-ω-fluoropropyl-2-β-carbo-methoxy-3-β-(4-iodophenyl)nortropane single photon emission computed tomography (123I-FP-CIT SPECT).
Six PD patients (five women and one man, aged 63.2 ± 5.6 years) underwent 123I-FP-CIT SPECT and clinical evaluation [Unified Parkinson's Disease Rating Scale (UPDRS) and Parkinson's Disease Quality of Life Scale (PDQL)] preoperatively, 8 and 13 months after EMCS. Striatum-to-occipital cortex, caudate-to-occipital cortex and putamen-to-occipital cortex 123I-FP-CIT uptake ratios were calculated using the region of interest method.
Total and part III UPDRS scores significantly decreased at 8 and 13 months after stimulation (P=0.02 and 0.04, respectively); UPDRS part II and PDQL scores improved after 13 months (P=0.02 and 0.04, respectively). No significant differences in 123I-FP-CIT uptake ratios between baseline and follow-up were found in the examined regions. However, a progressive reduction in 123I-FP-CIT uptake ratios in the striatum contralateral to the implant was found. In contrast, no further decrease in 123I-FP-CIT uptake ratios was detected in the striatum ipsilateral to the implant. There were no correlations between changes in 123I-FP-CIT uptake ratios with disease duration, changes in medication dosage and motor UPDRS scores.
Despite a small but highly selected sample of advanced PD patients, our results showed that no further dopamine transporter reduction occurred in the striatum ipsilateral to the implant side. This finding could lead to the hypothesis that EMCS might elicit a 'neuroprotective' effect, as suggested by significant clinical benefits.
Nuclear Medicine Communications 06/2012; 33(9):933-40. DOI:10.1097/MNM.0b013e3283561810 · 1.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To systematically review published data on the role of positron emission tomography (PET) or PET/computed tomography (PET/CT) using either Carbon-11 ((11)C) or Fluorine-18 ((18)F) choline tracer in tumors other than prostatic cancer. A comprehensive literature search of studies published in PubMed/MEDLINE and Embase databases through January 2012 and regarding (11)C-choline or (18)F-choline PET or PET/CT in patients with tumors other than prostatic cancer was carried out. Fifty-two studies comprising 1800 patients were included and discussed. Brain tumors were evaluated in 15 articles, head and neck tumors in 6, thoracic tumors (including lung and mediastinal neoplasms) in 14, liver tumors (including hepatocellular carcinoma) in 5, gynecologic malignancies (including breast tumors) in 5, bladder and upper urinary tract tumors in 5, and musculoskeletal tumors in 7. Radiolabeled choline PET or PET/CT is useful to differentiate high-grade from low-grade gliomas and malignant from benign brain lesions, to early detect brain tumor recurrences and to guide the stereotactic biopsy sampling. The diagnostic accuracy of radiolabeled choline PET is superior compared to Fluorine-18 fluorodeoxyglucose ((18)F-FDG) PET in this setting. Radiolabeled choline PET or PET/CT seems to be accurate in differential diagnosis between malignant and benign thoracic lesions and in staging lung tumors; nevertheless, a superiority of radiolabeled choline compared to (18)F-FDG has not been demonstrated in this setting, except for the detection of brain metastases. Few but significant studies on radiolabeled choline PET and PET/CT in patients with hepatocellular carcinoma (HCC) and musculoskeletal tumors are reported in the literature. The combination of radiolabeled choline and (18)F-FDG PET increases the detection rate of HCC. The diagnostic accuracy of radiolabeled choline PET or PET/CT seems to be superior compared to (18)F-FDG PET or PET/CT and conventional imaging methods in patients with bone and soft tissue tumors. Limited experience exists about the role of radiolabeled choline PET and PET/CT in patients with head and neck tumors, bladder cancer and gynecologic malignancies including breast cancer.
Annals of Nuclear Medicine 05/2012; 26(6):451-61. DOI:10.1007/s12149-012-0602-7 · 1.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
18F-fluoro-deoxy-glucose (18 F-FDG) positron emission tomography integrated/combined with computed tomography (PET-CT) provides the best diagnostic results in the metabolic characterization of undetermined solid pulmonary nodules. The diagnostic performance of 18 F-FDG is similar for nodules measuring at least 1 cm and for larger masses, but few data exist for nodules smaller than 1 cm.
We report five cases of oncologic patients showing focal lung 18 F-FDG uptake on PET-CT in nodules smaller than 1 cm. We also discuss the most common causes of 18 F-FDG false-positive and false-negative results in the pulmonary parenchyma.
In patient 1, contrast-enhanced CT performed 10 days before PET-CT did not show any abnormality in the site of uptake; in patient 2, high-resolution CT performed 1 month after PET showed a bronchiole filled with dense material interpreted as a mucoid impaction; in patient 3, contrast-enhanced CT performed 15 days before PET-CT did not identify any nodules; in patients 4 and 5, contrast-enhanced CT revealed a nodule smaller than 1 cm which could not be characterized. The 18 F-FDG uptake at follow-up confirmed the malignant nature of pulmonary nodules smaller than 1 cm which were undetectable, misinterpreted, not recognized or undetermined at contrast-enhanced CT.
In all five oncologic patients, 18 F-FDG was able to metabolically characterize as malignant those nodules smaller than 1 cm, underlining that: 18 F-FDG uptake is not only a function of tumor size but it is strongly related to the tumor biology; functional alterations may precede morphologic abnormalities. In the oncologic population, especially in higher-risk patients, PET can be performed even when the nodules are smaller than 1 cm, because it might give an earlier characterization and, sometimes, could guide in the identification of alterations missed on CT.
World Journal of Surgical Oncology 04/2012; 10(1):71. DOI:10.1186/1477-7819-10-71 · 1.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A 64-year-old man was referred to our center for metabolic characterization of 2 bilateral pulmonary lesions, incidentally detected at computed tomography (CT). F-FDG PET/CT scan showed a weak radiopharmaceutical uptake in both pulmonary lesions. A subsequent Ga-DOTANOC PET/CT showed intense radiopharmaceutical uptake in both pulmonary lesions. Subsequently, the patient underwent histopathological examinations of both lesions, which showed a synchronous well-differentiated pulmonary neuroendocrine carcinoma (typical carcinoid tumor). This case reports a rare occurrence of synchronous pulmonary carcinoid, highlighting the role of different PET tracers for metabolic characterization of pulmonary nodules.
Clinical nuclear medicine 04/2012; 37(4):e91-4. DOI:10.1097/RLU.0b013e3182444252 · 3.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Positron emission tomography (PET) is widely used in the diagnostic evaluation and staging of different malignant tumors. The role of PET/computed tomographic scan in detecting distant metastases in the workup of Ewing sarcoma in children or young adults is less well defined. We report a case of a boy affected by a metastatic Ewing sarcoma with cardiac asymptomatic metastasis detected by F-FDG PET/computed tomography.
[Show abstract][Hide abstract] ABSTRACT: We evaluated the relationships between the cerebral metabolic rate of glucose (CMRglu) measured by dynamic (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and the clinical and neuropsychological assessment before and after the surgical procedure in idiopathic normal pressure hydrocephalus (INPH) patients.
Eleven selected INPH patients underwent clinical assessment (modified Rankin scale, Krauss scale, Larsson categorization system and Stein-Langfitt scale), cognitive evaluation (Mini-Mental State Examination, MMSE) and dynamic (18)F-FDG PET/CT scan 3 days before and 1 week after ventricular shunt placement.
After shunting, the global CMRglu significantly increased (2.95 ± 0.44 vs 4.38 ± 0.68, p = 10(-7)) in all INPH patients with a mean percentage value of 48.7%. After shunting, no significant change was found in the Evans ratio whereas a significant decrease in all clinical scale scores was observed. Only a slight reduction in the MMSE was found. After shunting, a significant correlation between the global CMRglu value and clinical assessment was found (R (2) = 0.75, p = 0.024); indeed all clinical scale scores varied (decreasing) and the CMRglu value also varied (increasing) in all INPH patients.
Our preliminary data show that changes in the CMRglu are promptly reversible after surgery and that there is a relationship between the early metabolic changes and clinical symptoms, independently from the simultaneous changes in the ventricular size. The remarkable and prompt improvement in the global CMRglu and in symptoms may also have important implications for the current concept of "neuronal plasticity" and for the cells' reactivity in order to recover their metabolic function.
European Journal of Nuclear Medicine 02/2012; 39(2):236-41. DOI:10.1007/s00259-011-1950-6 · 5.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Primary pancreatic lymphoma (PPL) is an extremely rare disease which occurs in pancreas, accounts for less than 1% of extra-nodal malignant lymphomas and 0,5% of cases of pancreatic masses. We report the case of PPL in a 15 year-old boy suffering from Maturity Onset Diabetes of the Young type 3 (MODY3) diagnosed at the age of 1 year.
Mediterranean Journal of Hematology and Infectious Diseases 01/2012; 4(1):e2012005. DOI:10.4084/MJHID.2012.005
[Show abstract][Hide abstract] ABSTRACT: (1) To investigate the diagnostic value of some O-(2-[F]fluoroethyl)-L-tyrosine (F-18 FET) indices derived from the dynamic acquisition to differentiate low-grade gliomas from high-grade; (2) to analyze the course of tumor time-activity curves (TACs); and (3) to calculate the individual probability of a high-grade glioma using the logistic regression.
Seventeen low-grade (WHO I-II) and 15 high-grade (WHO III-IV) gliomas were studied with dynamic F-18 FET PET. Regions of interests were drawn over the tumor and contralateral brain, and TACs were analyzed. We considered early standardized uptake value (SUV), middle SUV, late SUV, early-to-middle SUV tumor ratio, early-to-late SUV tumor ratio; time to peak (Tpeak), in minutes, from the beginning of the dynamic acquisition up to the maximum SUV of the tumor; and SoD (sum of the frame-to-frame differences). To assess the individual probability of high-grade, logistic regression was also used.
High-grade gliomas showed significantly (P < 0.0001) higher values when compared with low-grade gliomas in early SUV, early-to-middle ratio, early-to-late ratio, Tpeak, and SoD. For the grading of gliomas, the best indices were early-to-middle ratio and Tpeak providing a diagnostic accuracy of 94%. TACs analysis provided an 87% diagnostic accuracy. For individual high-grade diagnosis, the logistic regression provided 93% sensitivity, 100% specificity, and 97% accuracy.
Early-to-middle SUV tumor ratio and Tpeak were the best indices for assessing the grading of gliomas. Since early-to-middle ratio derives from the first 35 minutes of the dynamic acquisition, the PET study could last half an hour instead of 1 hour. By logistic regression, it is possible to assess the individual probability of high-grade, useful for prognosis and treatment.
Clinical nuclear medicine 10/2011; 36(10):841-7. DOI:10.1097/RLU.0b013e3182291b40 · 3.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study was designed to review the emerging role of fluorine 18 fluorodeoxyglucose (¹⁸F-FDG)-positron emission tomography (PET) CT/computed tomography (PET/CT) in patients with mycobacteriosis.
A comprehensive literature search of published studies through October 2010 in PubMed/MEDLINE database regarding ¹⁸F-FDG-PET and PET/CT in patients with mycobacteriosis was performed.
Ultimately, we identified 16 studies comprising a total of 220 patients with mycobacteriosis. Main findings of the included studies are presented.
(1) Mycobacteriosis commonly causes increased ¹⁸F-FDG uptake; therefore, positive ¹⁸F-FDG-PET results should be interpreted with caution in differentiating benign from malignant abnormalities. (2) ¹⁸F-FDG-PET and PET/CT are potentially useful in detecting sites of Mycobacterium infection. (3) Dual-phase ¹⁸F-FDG-PET is not useful for the differential diagnosis between malignant lesions and sites of Mycobacterium infection. (4) ¹⁸F-FDG-PET and PET/CT are useful for the evaluation of disease activity and in monitoring response to therapy in patients with mycobacteriosis. (5) Dual-tracer PET and PET/CT are potentially useful for presumptive diagnosis of solitary pulmonary nodules.