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C Messa

Publications and source records attributed to C Messa.

At least 19 recordsLinked to original sources
PubMed2006

Integrated PET/CT as a first-line re-staging modality in patients with suspected recurrence of ovarian cancer.

PURPOSE: The aims of this study were to compare CT with PET/CT results in patients with suspected ovarian cancer recurrence and to assess the impact of the PET/CT findings on their clinical management. METHODS: Thirty-two consecutive patients with suspected ovarian cancer recurrence were retrospectively included in the study. Abdominal contrast-enhanced CT and PET/CT with [(18)F]FDG, in addition to conventional follow-up, were performed in all 32 patients. After the comparison between CT and PET/CT results, based on clinical reports, changes in the clinical management of patients (intermodality changes) due to PET/CT information were analysed. RESULTS: Twenty of the 32 patients were positive at CT (62.5%) versus 29 (90.6%) at PET/CT. Intermodality changes in management, i.e. use of a different treatment modality, after PET/CT examination were indicated in 14/32 (44%) patients. In particular, before PET/CT study, the planned management was as follows: wait-and-see in 7/32 (22%), further instrumental examinations in 4/32 (12%), chemotherapy in 10/32 (31%), diagnostic surgical treatment in 6/32 (19%) and surgical treatment in the remaining 5/32 (16%). After PET/CT study, wait-and-see was indicated in 1/32 (3%), further instrumental examinations in 7/32 (22%), chemotherapy in 16/32 (50%), diagnostic surgical treatment in 2/32 (6%) and surgical treatment in the remaining 6/32 (19%). CONCLUSION: Integrated PET/CT could detect tumour relapse in a higher percentage of patients than could CT. A change in the clinical management was observed in 44% of cases when PET/CT information was added to conventional follow-up findings.

Adult↗
PubMed2006

PET/CT and radiotherapy.

This article reviews the state of the art of PET/CT applications in radiotherapy, specifically its use in disease staging, patient selection, treatment planning and treatment evaluation. Diseases for which radiotherapy with radical intent is indicated will be considered, as well as those in which PET/CT may actually change the course of disease. The methodological and technological aspects of PET/CT in radiotherapy are discussed, focusing on the problem of target volume definition with CT and PET functional imaging and the problem of tumor motion with respect to imaging and dose delivery.

Humans↗
PubMed2005

Feasibility of [18F]FDG-PET and coregistered CT on clinical target volume definition of advanced non-small cell lung cancer.

AIM: To prospectively evaluate the impact of coregistered positron emission tomography (PET) and computed tomography (CT) in 3D conformal radiotherapy (3D-CRT) planning in patients with non-small lung cancer (NSCLC). METHODS: Twenty-one patients (median age: 57 years; range: 42-80 years) referred to 3D-CRT for NSCLC were recruited. Positron emission tomography with 18F-fluorodeoxyglucose ([18F]FDG-PET) and conventional CT images were coregistered (PET/CT images) using a commercial software package based on surface matching technique. Neoplastic areas were contoured on [18F]FDG-PET images with the aid of the correspondent CT image by a nuclear medicine physician. CT images and their relative PET contours were then transferred to treatment planning system. A radiation oncologist firstly contoured clinical target volumes (CTV) on CT scan alone (CTV-CT), and then on coregistered PET/CT images (CTV-PET/CT). CTV-CT and CTV-PET/CT were compared for each patient; a difference higher than 25% was considered of clinical relevance. RESULTS: Three patients were shifted to palliative radiotherapy for metastatic disease or very large tumor size, showed by [18F]FDG-PET. Of the remaining 18 patients a CTV change, after inclusion of PET/CT data, was observed in 10/18 cases (55%): larger in 7/18 (range 33-279%) and smaller in 3/18 patients (range 26-34%), mainly due to inclusion or exclusion of lymph-nodal disease and to better definition of tumor extent. CTV changes smaller than 25% occurred in the remaining 8/18 patients. CONCLUSIONS: [18F]FDG-PET and CT images co-registration in radiotherapy treatment planning led to a change in CTV definition in the majority of our patients, which may significantly modify management and radiation treatment modality in these patients.

Adult↗
PubMed2005

Automatic registration of PET and CT studies for clinical use in thoracic and abdominal conformal radiotherapy.

AIM: Implementation and validation of an automatic registration method based on mutual information (MI) for the integration of thoracic and abdominal positron emission tomography (PET)/computed tomography (CT) studies, with the purpose to facilitate in a clinical context the inclusion of PET metabolic information in conformal radiotherapy (RT). METHODS: Registration was obtained by modeling a rigid spatial transformation between CT and PET transmission studies. The registration method was based on Normalized Mutual Information (NMI), by iteratively transforming the PET volume, until its optimal alignment to the CT study is achieved, in correspondence of the maximum of NMI. To avoid entrapment in local maxima and to improve convergence speed we introduced a multiresolution scheme. Accuracy of the proposed approach was investigated in experimental data, relative to phantom and patient studies, acquired in conditions similar to clinical situations. RESULTS: In phantom studies the mean error in the 3D space is 3.6 mm (range 3-4 mm) in thoracic region and 3.2 mm (range 2.9-3.7 mm) in abdominal region, considerably less than PET spatial resolution. In patient studies the spatial mean error increases with respect to phantom studies (5.4 mm and 5.2 mm for thorax and abdomen, respectively) but remains comparable to the PET spatial resolution. The accuracy of spatial realignment was thus found adequate for the registration of PET/CT registration, if good patient repositioning was adopted. CONCLUSIONS: The proposed registration method, based on MI, was validated for the integration of PET/CT studies of patients candidate for thoracic and abdominal conformal RT. The method is automatic and provided with a user interface, thus suitable for clinical use.

Abdominal Neoplasms↗
PubMed2004

Multi-modal medical image integration to optimize radiotherapy planning in lung cancer treatment.

This work presents a method for CT and PET image registration, and multi-modal analysis, to optimize radiotherapy planning in lung cancer treatment. The method relies on an image registration technique based on fiducial external markers to realign, spatially, PET images with the CT spatial reference system. The method was set up for clinical use in radiotherapy, allowing minimal modifications to be introduced in the management of patients undergoing radiation treatment. The accuracy of the registration technique was evaluated on patient studies in terms of Target Registration Error and was found to be less than 6.40 mm. The method was applied in the treatment planning of five patients affected by non-small-cell lung cancer, revealing the usefulness of PET/CT integration in delineating the extension of both the tumor mass and the tissues involved in the neoplastic process. Moreover, the functional information provided by PET often led to alterations in the treatment planning, changing the size and/or direction of radiation portals. The proposed method for PET/CT integration has been confirmed as being useful for optimizing radiotherapy planning in lung cancer treatment.

Algorithms↗
PubMed2004

PET/CT in diagnostic oncology.

In the last years positron emission tomography (PET) with 18F-fluorodeoxyglucose ([18F]FDG) has become an established technique for the staging and follow-up of a wide variety of neoplasms. As PET imaging is based on the physiological mediated distribution of the administered tracer, rather than on anatomic and structural characteristics of tissue, the addition of CT imaging to PET improves the interpretation of PET images. Recently, integrated PET/CT scanners have been developed that can produce directly functional PET and anatomical CT data 1 session, without moving the patient and with minimal delay between the reconstruction and fusion of the 2 image data sets. In addition, CT images are also being used for attenuation correction in the reconstruction process of the PET emission data. A brief review of the most relevant technical characteristics of 3 PET/CT systems, which represent the state of the art of this technology, are described. Furthermore an overview of PET/CT acquisition protocols and clinical applications of PET/CT in oncology are described. Overall, advantages of PET/CT over PET that may influence the clinical routine, have been identified as a) the shorter image acquisition time with benefit on patients throughput and on patient compliance, b) the better accuracy in anatomically localizing focal areas of abnormal tracer uptake and defining tumor extent and c) the possibility to stage a disease in 1 single step.

Fluorodeoxyglucose F18↗
PubMed2003

Helicobacter pylori is associated with modified lipid profile: impact on Lipoprotein(a).

OBJECTIVES: Helicobacter pylori is a controversial risk factor for atherosclerosis. We investigated whether the bacterium persistent inflammation or the expression of the cytotoxin-associated gene A (CagA) may affect serum lipids as well as Lipoprotein(a). DESIGN AND METHODS: Two hundred-eleven healthy volunteers were evaluated for lipids and Lipoprotein(a). Helicobacter pylori was characterized by Urea Breath Test and IgG-anti-CagA. apo(a) Kringle-IV polymorphism was genotyped. RESULTS: Prevalence of the infection was 72%; 43% of subjects expressed CagA reactivity. Infected subjects showed increased levels of cholesterol, LDL-cholesterol, and cholesterol/HDL-cholesterol atherogenic index. Association with the Helicobacter pylori CagA(-) strains persisted after the adjustment for covariates. Significant difference between infected and uninfected subjects was found in Lipoprotein(a) levels. This difference did not arise from the Kringle-IV genotype. CONCLUSIONS: The infection per se significantly modified serum lipid and Lipoprotein(a) concentrations. CagA does not seem to be a reliable marker of pathogenicity for the atherogenic complications of H. pylori infection.

Adult↗
PubMed2003

[18F]fluorodeoxyglucose positron emission tomography as a useful indicator of metastatic gestational trophoblastic tumor: preliminary results in three patients.

OBJECTIVE: The goal of this study was to evaluate the usefulness of positron emission tomography with [(18)F]fluorodeoxyglucose ([(18)F]FDG-PET) in detecting metastases in patients with gestational trophoblastic tumor (GTTs). METHODS: A retrospective study was conducted on three patients with GTTs who had been studied with [(18)F]FDG-PET and computed tomography (CT) after an increase in human chorionic beta-gonadotropin (betahCG) serum levels. PET scans were performed with a multiring whole-body positron emission tomograph 45 min after an intravenous bolus injection of [(18)F]FDG ( approximately 5.2 MBq/kg). CT studies were obtained on a spiral scanner prior and after administration of intravenous iodinated contrast material. Within a week of CT and [(18)F]FDG-PET studies, the patients underwent surgical procedures for histological diagnosis. RESULTS: In one patient, a lung lesion positive for neoplastic tissue with [(18)F]FDG-PET and negative with CT was confirmed to be a GTT metastasis at histology. In another patient, [(18)F]FDG-PET was negative, while CT was positive for the presence of lung metastasis; no viable tumor tissue was found at histological analysis. The remaining patient had a positive [(18)F]FDG-PET and CT study for lung metastasis; this was confirmed at histological analysis. In the same patient, both [(18)F]FDG-PET and CT depicted the presence of a liver lesion. Necrotic lesion regression after treatment was clearly documented with [(18)F]FDG-PET only. CONCLUSIONS: Our preliminary results suggest that [(18)F]FDG-PET may be useful for the assessment of metastatic disease in patients with GTTs.

Adult↗
PubMed2003

Value of [11C]choline-positron emission tomography for re-staging prostate cancer: a comparison with [18F]fluorodeoxyglucose-positron emission tomography.

PURPOSE: We compared [11C]choline-positron emission tomography (PET) with [18F]fluorodeoxyglucose-PET for re-staging prostate cancer in a group of 100 patients. MATERIALS AND METHODS: A total of 100 consecutive patients referred for whole body [18F]fluorodeoxyglucose-PET for clinical prostate re-staging after radical treatment for prostate cancer were retrospectively included in the study. Mean prostate specific antigen (PSA) was 6.57 ng./ml. In all cases [11C]choline-PET was also performed. PET studies were done with a multiring device 5 minutes after intravenous injection of approximately 370 MBq. [11C]choline and 60 minutes after injection of approximately 370 MBq. [18F]fluorodeoxyglucose. PET findings were compared with those obtained with different conventional imaging and with PSA assessed at the time of PET and 1 year later. RESULTS: Areas of abnormal focal increases were noted in 47% of patients on [11C]choline-PET and in 27% on [18F]fluorodeoxyglucose-PET. Of the 100 patients 49 had positive conventional imaging findings. All except 14 [11C]choline-PET findings were concordant with conventional imaging, including 6 negative and 8 positive conventional imaging results. All except 1 [11C]choline-PET negative cases also had negative conventional imaging after 1 year. PSA at 1 year remained stable or decreased in 80% and 62% of [11C]choline-PET negative and positive cases, respectively. CONCLUSIONS: [11C]choline-PET seems to be useful for re-staging prostatectomy cases with increasing serum PSA levels. It is superior to [18F]fluorodeoxyglucose-PET and complementary to conventional imaging but with the advantage of staging disease at a single step.

Aged↗
PubMed2003

Advanced ovarian carcinoma: usefulness of [(18)F]FDG-PET in combination with CT for lesion detection after primary treatment.

AIM: To determine the additional value of [(18)F]FDG-PET in combination with computed tomography (CT) over CT used alone, for evaluating ovarian cancer patients after primary treatment. METHODS: Twenty-five women (mean age: 53.6 years) had primary debulking surgery followed by chemotherapy for histologically proven ovarian carcinoma. At initial diagnosis, the tumor types were papillary serous adenocarcinoma (n=20), endometroid carcinoma (n=3), mixed mullerian tumor (n=1), and granulosa cell tumor (n=1). All patients underwent [(18)F]FDG-PET and contrast enhanced CT examinations, within 30 days of the completion of chemotherapic treatment. [(18)F]FDG-PET images were interpreted with the knowledge of CT findings (PET+CT); conversely, CT images were evaluated with no knowledge of the [(18)F]FDG-PET results. Within 7 day of imaging studies, 2(nd)-look laparoscopy (n=7) or laparotomy (n=18) was performed for histological confirmation. In all cases, imaging findings were then correlated with results of histopathologic examination. RESULTS: Of the 23 neoplastic viable lesions, all histologically confirmed, 16 could be detected by CT alone and 19 by PET+CT. An inflammatory lymph-node was misdiagnosed as viable tumor with both PET+CT and CT alone; an area of scar tissue in the presacral region was also misinterpreted as malignant tissue with CT alone. Overall lesion-based sensitivity, specificity and accuracy in assessing focal areas of residual tumor were as follows: 69.56%, 83.33%, 74.28% for CT, and 82.60%, 91.67%, 85.71% for PET+CT. The negative predictive value of PET+CT was markedly higher (73.33%), compared to that of CT alone (58.82%). CONCLUSION: PET used in combination with CT allows to accurately assess tumor response. A major advantage of PET+CT over CT alone is in excluding the presence of residual viable lesions after treatment.

Adult↗
PubMed2002

In vivo serotonin 5HT(2A) receptor binding and personality traits in healthy subjects: a positron emission tomography study.

Using positron emission tomography (PET) and [(11)C]raclopride, an association between striatal D(2) dopamine receptors and emotional detachment has been recently reported. Several laboratory findings indicate a link between the serotoninergic system and harm avoidance. In this study we investigated, in a group of healthy volunteers, the relationship between the in vivo binding of 3-(2'-[(18)F]fluoroethyl)spiperone ([(18)F]FESP) to cortical 5HT(2) and striatal D(2) receptors and three personality dimensions, i.e., "novelty seeking," "reward dependence," and "harm avoidance." Eleven healthy volunteers were evaluated by means of the Tridimensional personality Questionnaire (C. R., Arch. Gen. Psychiatry 44: 573-588.) and underwent a PET scan with [(18)F]FESP. Harm avoidance showed a significant inverse correlation with [(18)F]FESP binding in the cerebral cortex, particularly in the frontal cortex (R(2) = -0.709, P = 0.0145) and left parietal cortex (R = -0.629, P = 0.038) but not in the basal ganglia (r = -0.176, P = 0.651). Similar results were obtained using SPM at a P threshold of 0.05. No significant correlation was observed with novelty seeking or reward dependence. In the cerebral cortex, high values of [(18)F]FESP binding values are associated with a high tendency to avoid danger, indicating involvement of the serotoninergic system and, in particular, 5HT(2A) receptors, in this trait of personality. The results of this as well as of previous studies on personality dimensions indicate the existence of a relationship between behavioral and neurobiological factors. In addition these results support the concept that the variability of PET data may be explained by neurochemical differences related to the prevalence of specific personality traits.

Adult↗
PubMed2002

New perspectives on neurochemical effects of amantadine in the brain of parkinsonian patients: a PET - [(11)C]raclopride study.

Amantadine, is a non competitive NMDA receptors antagonist that has been proved beneficial in Parkinson's disease. However its mechanism of action at therapeutic doses is still under discussion. Aim of this study was to evaluate the effect of repeated administration of amantadine on striatal dopaminergic system by measuring [(11)C]raclopride binding to striatal D(2) dopamine receptors, in patients with moderate idiopathic Parkinson's disease. Eight patients completed the study undergoing a PET scan, before and after 10-14 days treatment with Amantadine (200 mg/day). Patients were on treatment with L-DOPA, which was suspended 1 night before each PET scans, and free from dopaminergic agonists, anticholinergic and antidepressants. Amantadine treatment significantly increased [(11)C-]Raclopride binding (caudate: 10% p = 0.04; putamen 11% p = 0.01). A slight reduction (-7.3%, p = 0.062) of UPDRS total scores was also observed. The increased availability of striatal D(2) receptors, is likely to be caused by drug induced modification of receptors expression. This hypothesis is consistent with previous experiments, indicating an increase in striatal D(2) receptors in rats treated with amantadine or other non competitive NMDA antagonists and suggests that the neo-synthesis of D(2) receptors may represent a reinforcing mechanism of drug efficacy.

Aged↗
PubMed2001

Oestrogen receptors and microsatellite instability in colorectal carcinoma patients.

About 10-15% of sporadic colorectal cancers show microsatellite instability (MIN), a mutator phenotype of mismatch repair genes. It seems that oestrogens may inhibit the pathway to colorectal carcinoma which involves a mismatch repair deficiency. Oestrogen receptorial status was evaluated in the neoplastic tissue and uninvolved surrounding mucosa of 17 MIN-positive and 33 MIN-negative tumours using an immunoenzymatic assay. MIN status was examined using the polymerase chain reaction and specific microsatellite markers. MIN was significantly associated with very low levels of oestrogen receptor in tumour tissue. Our findings suggest that MIN-positive tumours might lose a possible oestrogenic modulation mechanism.

Adult↗
PubMed2001

PET in psychopharmacology.

Emission tomography techniques and, in particular, positron emission tomography (PET) enable the in vivo study of several physiological and neurochemical variables in human subjects using methods originally developed for quantitative autoradiography. In particular, PET allows one to evaluate in human subjects: (a) the effect of specific neurochemical challenges on regional brain function at rest or under activation; (b) the activity of neurotransmitters and the regional expression of specific molecular targets during pathology including their modulation by drug treatment; (c) the kinetics of drug disposition and activity directly in the target organ. This is of primary interest in the field of biological psychiatry and in psychoactive drugs development, where it is particularly difficult to reproduce human diseases using animal models in view of the peculiarity of this field and the large heterogeneity of each psychiatric illness also inside the same clinical definition. The aim of this paper is to review the principal strategies and the main results of the use of PET in psychopharmacology.

Animals↗
PubMed2001

A PET study with [11-C]raclopride in Parkinson's disease: preliminary results on the effect of amantadine on the dopaminergic system.

Amantadine has been proved to be beneficial in Parkinson's disease. Although it is still uncertain which neurochemical events are modified at therapeutic doses, an increase in dopaminergic tone secondary to NMDA receptor blockade and a direct inhibition of the glutamatergic overactivity have been suggested to be involved in its clinical effects. The aim of this study was to evaluate the effects of amantadine on the dopaminergic system by measuring the in vivo binding of [11-C]raclopride to D2 dopamine receptors in the basal ganglia of 6 patients with idiopathic Parkinson's disease. Each patient underwent a PET study, before and after 14 days of treatment with amantadine (200 mg/day). Repeated treatment with therapeutic doses of amantadine induced a moderate increase in the in vivo binding of [11C]raclopride in the putamen of PD patients. This observation indicates that in PD patients, 200 mg/day amantadine does not produce an increase in extracellular levels of dopamine sufficiently to inhibit raclopride binding or that, if present, is it masked by a concurrent increase in receptor availability, as recently reported in rat striatum.

Aged↗