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131.
Value of 18-Fluorodeoxyglucose Positron Emission Tomography in the Management of Patients With Cystic Tumors of the Pancreas 总被引:17,自引:0,他引:17
Cosimo Sperti Claudio Pasquali Franca Chierichetti Guido Liessi Giorgio Ferlin Sergio Pedrazzoli 《Annals of surgery》2001,234(5):675-680
OBJECTIVE: To assess the reliability of 18-fluorodeoxyglucose positron emission tomography (18-FDG PET) in distinguishing benign from malignant cystic lesions of the pancreas. SUMMARY BACKGROUND DATA: The preoperative differential diagnosis of cystic lesions of the pancreas remains difficult: the most important point is to identify malignant or premalignant cysts that require resection. 18-FDG PET is a new imaging procedure based on the increased glucose metabolism by tumor cells and has been proposed for the diagnosis and staging of pancreatic cancer. METHODS: During a 4-year period, 56 patients with a suspected cystic tumor of the pancreas underwent 18-FDG PET in addition to computed tomography scanning, serum CA 19-9 assay, and in some instances magnetic resonance imaging or endoscopic retrograde cholangiopancreatography. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value. The accuracy of 18-FDG PET and computed tomography was determined for preoperative diagnosis of a malignant cyst. RESULTS: Seventeen patients had malignant tumors. Sixteen patients (94%) showed 18-FDG uptake with a standard uptake value of 2.6 to 12.0. Twelve patients (70%) were correctly identified as having malignancy by computed tomography, CA 19-9 assay, or both. Thirty-nine patients had benign tumors: only one mucinous cystadenoma showed increased 18-FDG uptake (standard uptake value 2.6). Five patients with benign cysts showed computed tomography findings of malignancy. Sensitivity, specificity, and positive and negative predictive values for 18-FDG PET and computed tomography scanning in detecting malignant tumors were 94%, 97%, 94%, and 97% and 65%, 87%, 69%, and 85%, respectively. CONCLUSIONS: 18-FDG PET is more accurate than computed tomography in identifying malignant pancreatic cystic lesions and should be used, in combination with computed tomography and tumor markers assay, in the preoperative evaluation of patients with pancreatic cystic lesions. A positive result on 18-FDG PET strongly suggests malignancy and, therefore, a need for resection; a negative result shows a benign tumor that may be treated with limited resection or, in selected high-risk patients, with biopsy, follow-up, or both. 相似文献
132.
133.
Paola Cassoni Lorenzo Daniele Elena Maldi Luisella Righi Veronica Tavaglione Silvia Novello Marco Volante Giorgio Vittorio Scagliotti & Mauro Papotti 《Histopathology》2009,55(1):20-27
Aims: To study caveolin-1 (Cav-1) expression in metastatic lung carcinomas.
Methods and results: Cav-1 expression was investigated in a series of 121 lung carcinomas and it was shown that 18/121 tumours (14.9%) were Cav-1+. None of the pure bronchioloalveolar carcinomas proved to be positive, vs. 42.8% of the large cell carcinomas (neuroendocrine subtype excluded). Adenocarcinomas (8.5%), large cell neuroendocrine carcinomas (20%) and squamous cell carcinomas (29.6%) displayed an intermediate percentage of positive cases, suggesting a gradient of Cav-1 expression according to tumour histotype-related aggressiveness. Moreover, the percentage of Cav-1+ tumours with distant metastases was almost double that of non-metastatic tumours (17.8% vs. 8.1%), irrespective of the histotype. In 34 tumours metastatic to the brain, primary and secondary lesions were compared and 53% of brain metastases were Cav-1+ vs. 20.6% of primaries, indicating a de novo acquisition of Cav-1 expression. This pattern was exclusive to the brain, as it was not acquired in adrenal metastases. In our series, the presence of epidermal growth factor receptor amplification, determined by fluorescence in situ hybridization, was not related to Cav-1 reactivity.
Conclusions: Cav-1 immunoreactivity in lung carcinoma is histotype-dependent and acquired de novo in brain metastases, suggesting a site-specific phenotypic shift in secondary lesions. 相似文献
Methods and results: Cav-1 expression was investigated in a series of 121 lung carcinomas and it was shown that 18/121 tumours (14.9%) were Cav-1+. None of the pure bronchioloalveolar carcinomas proved to be positive, vs. 42.8% of the large cell carcinomas (neuroendocrine subtype excluded). Adenocarcinomas (8.5%), large cell neuroendocrine carcinomas (20%) and squamous cell carcinomas (29.6%) displayed an intermediate percentage of positive cases, suggesting a gradient of Cav-1 expression according to tumour histotype-related aggressiveness. Moreover, the percentage of Cav-1+ tumours with distant metastases was almost double that of non-metastatic tumours (17.8% vs. 8.1%), irrespective of the histotype. In 34 tumours metastatic to the brain, primary and secondary lesions were compared and 53% of brain metastases were Cav-1+ vs. 20.6% of primaries, indicating a de novo acquisition of Cav-1 expression. This pattern was exclusive to the brain, as it was not acquired in adrenal metastases. In our series, the presence of epidermal growth factor receptor amplification, determined by fluorescence in situ hybridization, was not related to Cav-1 reactivity.
Conclusions: Cav-1 immunoreactivity in lung carcinoma is histotype-dependent and acquired de novo in brain metastases, suggesting a site-specific phenotypic shift in secondary lesions. 相似文献
134.
Alanine aminotransferase predicts coronary heart disease events: a 10-year follow-up of the Hoorn Study. Schindhelm RK, Dekker JM, Nijpels G, Bouter LM, Stehouwer CD, Heine RJ, Diamant M. Alanine aminotransferase (ALT) is a marker of non-alcoholic fatty liver disease (NAFLD) and predicts incident type 2 diabetes mellitus (DM2). Recently, ALT was shown to be also associated with endothelial dysfunction and carotid atherosclerosis. We studied the predictive value of ALT for all-cause mortality, incident cardiovascular disease (CVD) and coronary heart disease (CHD) events in a population-based cohort of Caucasian men and women aged 50-75 years, at baseline. The 10-year risk of all-cause mortality, fatal and non-fatal CVD and CHD events in relation to ALT was assessed in 1439 subjects participating in the Hoorn Study, using Cox survival analysis. Subjects with prevalent CVD/CHD and missing data were excluded. As compared with the first tertile, the age- and sex-adjusted hazard ratios (95% confidence intervals) for all-cause mortality, CVD events and CHD events were 1.30 (0.92-1.83), 1.40 (1.09-1.81) and 2.04 (1.35-3.10), respectively, for subjects in the upper tertile of ALT. After adjustment for components of the metabolic syndrome and traditional risk factors, the association of ALT and CHD events remained significant for subjects in the third relative to those in the first tertile, with a hazard ratio of 1.88 (1.21-2.92) and 1.75 (1.12-2.73), respectively. In conclusion, the predictive value of ALT for coronary events, seems independent of traditional risk factors and the features of the metabolic syndrome in a population-based cohort. Further studies should confirm these findings and elucidate the pathophysiological mechanisms. [Abstract reproduced by permission of Atherosclerosis 2007;191:391-396]. 相似文献
135.
Prof. Leonardo Marzio MD Matteo Neri MD Anna Maria Di Giammarco MD Franco Cuccurullo MD Giorgio Assuero Lanfranchi MD 《Digestive diseases and sciences》1986,31(4):349-354
The effect of dopamine on human gastric and small intestinal interdigestive motility was investigated in 12 subjects. Intestinal motility was recorded by means of a four-lumen polyvinyl probe with four open tips located 15 cm apart, continuously perfused with distilled water. In each subject during the same study, after recording two consecutive spontaneous phase III of migrating myoelectrical complexes and when a phase II appeared, dopamine was infused intravenously twice in a dose of 5 g/kg/min for 15 min with an interval of 20 min between each infusion. In six subjects, the second dopamine infusion was preceded by a treatment with sulpiride (10 mg, intravenously, as bolus) or domperidone (10 mg, intravenously, as bolus), each considered a highly selective dopamine antagonist. The results show that dopamine stimulates duodenal motility producing a pattern similar to that observed in phase III of spontaneously occurring migrating myoelectrical complexes. The second dopamine infusion reproduced in all cases the same pattern of motility as observed during the first infusion. Sulpiride and domperidone prevented the effect of dopamine in all cases. It is therefore suggested that dopamine-induced duodenal motility may involve specific dopaminergic receptors. 相似文献
136.
Baroldi G Silver MD Parolini M Pomara C Turillazzi E Fineschi V 《International journal of cardiology》2005,100(3):435-441
BACKGROUND: Electrophysiologically, ventricular fibrillation is defined as a "chaotic, random, asynchronous electrical activity of the ventricles due to repetitive re-entrant excitation and/or rapid focal discharge". To this point its morphological equivalent has not been defined. MATERIAL AND METHOD: Several groups of different diseases and types of accidental death in normal subjects were studied. A complete autopsy was performed and the hearts were examined in 432 cases. A total of 16 myocardial samples per heart were processed for histological examination and sections were stained by haematoxylin and eosin or by specific stains. The frequency, location and extent of myocellular segmentation (stretching and/or rupture) of intercalated discs and associated changes of myocardial bundles and single myocells were investigated. A quantitative analysis was performed and the data were processed for statistical evaluation. RESULTS: The frequency of MFB was maximal in coronary (88%) and Chagas (76%) groups followed by the intracranial brain haemorrhage group (52%). The extent of myofiberbreak-up was maximal in coronary/Chagas groups followed by intracranial haemorrhage and transplant groups. CONCLUSIONS: No correlation was seen between gender, age, heart weight, degree of coronary atherosclerosis, myocardial fibrosis, survival and MFB. If our postulate is correct, finding MFB in the myocardium might allow the diagnosis of a malignant arrhythmia followed by cardiac arrest due to ventricular fibrillation even in the absence of clinical information (sudden death out-of-hospital). 相似文献
137.
ras and c-myc protein expression in colorectal carcinoma 总被引:6,自引:0,他引:6
Felice Miller M.D. Tomas M. Heimann M.D. Astrid Quish M.D. Daniel J. Pyo M.D. Arnold Szporn M.D. Giorgio Martinelli Ph.D. Thomas M. Fasy M.D. Ph.D. 《Diseases of the colon and rectum》1992,35(5):430-435
This study was performed to determine the correlation of tumor ras and c-myc oncogene expression with clinical and prognostic variables in patients prone to develop colorectal cancer. One hundred eighteen patients with colorectal cancer were studied; mean age was 40 years. Fifty-three were young patients (age 40 or less), 49 had ulcerative colitis, and 16 had multiple polyposis coli. Immunoperoxidase stains of paraffin-embedded cancer sections were performed for the c-myc and ras proteins. ras staining was found to correlate with Dukes stage and prognosis. Patients with tumors negative for ras protein stain had an actuarial five-year survival of 61 percent versus 44 percent for those tumors with a positive stain (P less than 0.05). This correlation was not seen with the c-myc stain. Positive ras oncogene stain appears to be a useful indicator of advanced stage and poor prognosis in colorectal cancer occurring in cancer-prone patients. 相似文献
138.
139.
Elena Geuna Andrea Milani Rossella Martinello Caterina Aversa Giorgio Valabrega Maurizio Scaltriti 《Expert opinion on investigational drugs》2015,24(3):421-431
Introduction: Deregulation of the phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) intracellular signaling pathway is common in breast cancer (BC) and has been found to be potentially implicated in resistance to endocrine and anti-HER2 therapies. Targeting the PI3K/Akt/mTOR pathway may remove this inhibition and restore sensitivity to these compounds. Buparlisib (BKM120) is a potent oral pan-class I PI3K inhibitor that is being extensively evaluated in multiple tumor types.Areas covered: This review briefly summarizes the pharmacodynamics and pharmacokinetics of buparlisib, focusing on preclinical and clinical data in BC and on ongoing randomized trials.Expert opinion: Overall, buparlisib is a safe and tolerable drug and, despite its peculiar toxicity profile, it is suitable for studies in combination with other anticancer agents in BC. Early-phase clinical trials in BC have provided evidence of antitumor activity. Several trials are being conducted in all the biological subsets of BC, including combinations with endocrine therapy, anti-HER2 agents, PARP-inhibitors and chemotherapy. While clinical results are eagerly awaited, biological material suitable for both genomic and non-genomic analyses is being collected. The authors expect an intense investigation of the potential biomarkers that explain response or resistance to buparlisib and inspire strategies to rationally explore the therapeutic potential of this drug. 相似文献
140.
Gagliardi Federica Lauro Augusto Tripodi Domenico Amabile Maria Ida Palumbo Piergaspare Di Matteo Filippo Maria Palazzini Giorgio Forte Flavio Frattaroli Stefano Khouzam Simone Marino Ignazio R. DAndrea Vito Sorrenti Salvatore Pironi Daniele 《Digestive diseases and sciences》2022,67(3):786-798
Digestive Diseases and Sciences - Mesenteric cysts are defined as a heterogeneous group of intra-abdominal cystic lesions of the mesentery or omentum that may be found in any portion of the... 相似文献