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1.
Dis Esophagus ; 29(2): 197-204, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25516110

RESUMEN

A wide variety of pieces of evidence has suggested that obesity is associated with a significant increase in the risk for gastroesophageal reflux disease (GERD) symptoms and its complications. The aim of this study was to evaluate the effect of weight loss on reflux symptoms in overweight/obese patients with proven GERD. We enrolled overweight/obese patients with typical GERD symptoms and erosive esophagitis. At baseline, patients underwent detailed reflux symptoms evaluation and anthropometric assessment, and were divided into two treatment groups: group A received proton pump inhibitor (PPI) and a personalized hypocaloric diet and aerobic exercise; and group B received PPI and a 'standard of care diet'. The dietetic treatment was considered effective if at least 10% of weight loss was achieved within 6 months. All patients were evaluated in terms of anthropometric data, GERD symptoms, and PPI use. In group A, mean body mass index (BMI) decreased from 30.3 ± 4.1 to 25.7 ± 3.1 (P < 0.05), and mean weight decreased from 82.1 ± 16.9 kg to 69.9 ± 14.4 kg (P < 0.05). In group B, there was no change in BMI and weight. Symptom perception decreased (P < 0.05) in both groups during PPI therapy, but a higher improvement was recorded in group A. In group A, PPI therapy was completely discontinued in 27/50 of the patients, and halved in 16/50. Only 7/50 continued the same PPI dosage. In group B, 22/51 halved the therapy and 29/51 maintained full dosage of therapy, but none was able to discontinue PPI due to a symptom recurrence. Overall, weight loss of at least 10% is recommended in all patients with GERD in order to boost the effect of PPI on reflux symptom relief and to reduce chronic medication use.


Asunto(s)
Reflujo Gastroesofágico/tratamiento farmacológico , Obesidad/terapia , Sobrepeso/terapia , Inhibidores de la Bomba de Protones/administración & dosificación , Pérdida de Peso , Adulto , Índice de Masa Corporal , Dieta Reductora/métodos , Esofagitis/tratamiento farmacológico , Esofagitis/etiología , Terapia por Ejercicio/métodos , Femenino , Reflujo Gastroesofágico/etiología , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/fisiopatología , Sobrepeso/complicaciones , Sobrepeso/fisiopatología
2.
Dis Esophagus ; 29(1): 3-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25212408

RESUMEN

Multichannel impedance pH monitoring has shown that weakly acidic refluxes are able to generate heartburn. However, data on the role of different pH values, ranging between 4 and 7, in the generation of them are lacking. The aim of this study was to evaluate whether different pH values of weakly acidic refluxes play a differential role in provoking reflux symptoms in endoscopy-negative patients with physiological esophageal acid exposure time and positive symptom index and symptom association probability for weakly acidic refluxes. One hundred and forty-three consecutive patients with gastroesophageal reflux disease, nonresponders to proton pump inhibitors (PPIs), were allowed a washout from PPIs before undergoing: upper endoscopy, esophageal manometry, and multichannel impedance pH monitoring. In patients with both symptom index and symptom association probability positive for weakly acidic reflux, each weakly acidic reflux was evaluated considering exact pH value, extension, physical characteristics, and correlation with heartburn. Forty-five patients with normal acid exposure time and positive symptom association probability for weakly acidic reflux were identified. The number of refluxes not heartburn related was higher than those heartburn related. In all distal and proximal liquid refluxes, as well as in distal mixed refluxes, the mean pH value of reflux events associated with heartburn was significantly lower than that not associated. This condition was not confirmed for proximal mixed refluxes. Overall, a low pH of weakly acidic reflux represents a determinant factor in provoking heartburn. This observation contributes to better understand the pathophysiology of symptoms generated by weakly acidic refluxes, paving the way toward the search for different therapeutic approaches to this peculiar condition of esophageal hypersensitivity.


Asunto(s)
Monitorización del pH Esofágico/métodos , Reflujo Gastroesofágico , Pirosis , Concentración de Iones de Hidrógeno , Percepción del Dolor/fisiología , Adulto , Esófago/fisiopatología , Femenino , Determinación de la Acidez Gástrica , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/fisiopatología , Pirosis/diagnóstico , Pirosis/etiología , Pirosis/fisiopatología , Pirosis/psicología , Humanos , Masculino , Manometría/métodos , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/uso terapéutico , Estadística como Asunto , Evaluación de Síntomas
3.
J Hazard Mater ; 306: 115-123, 2016 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-26705888

RESUMEN

We studied the strategy of an Aspergillus fumigatus strain able to grow on metal cyanide wastes to cope with silver. The tolerance test revealed that the Minimum Inhibitory Concentration of Ag(I) was 6mM. In 1mM AgNO3 aqueous solution the fungus was able to reduce and sequestrate silver into the cell in the form of nanoparticles as evidenced by the change in color of the biomass and Electron Microscopy observations. Extracellular silver nanoparticle production also occurred in the filtrate solution after previous incubation of the fungus in sterile, double-distilled water for 72h, therefore evidencing that culture conditions may influence nanoparticle formation. The nanoparticles were characterized by UV-vis spectrometry, X-ray diffraction and Energy Dispersion X-ray analysis. Atomic absorption spectrometry revealed that the optimum culture conditions for silver absorption were at pH 8.5.The research is part of a polyphasic study concerning the behavior of the fungal strain in presence of metal cyanides; the results provide better understanding for further research targeted at a rationale use of the microorganism in bioremediation plans, also in view of possible metal recovery. Studies will be performed to verify if the fungus maintains its ability to produce nanoparticles using KAg(CN)2.


Asunto(s)
Aspergillus fumigatus/efectos de los fármacos , Cianuros/metabolismo , Nanopartículas del Metal/toxicidad , Nitrato de Plata/toxicidad , Aspergillus fumigatus/metabolismo , Aspergillus fumigatus/ultraestructura , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión
4.
Neurogastroenterol Motil ; 26(1): 28-35, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23992024

RESUMEN

BACKGROUND: A short-course of proton pump inhibitors (PPIs) is often used to confirm gastroesophageal reflux disease (GERD). However, some patients with PPI responsive heartburn do not seem to have evidence of GERD on impedance-pH monitoring (MII-pH). The aim of the study was to evaluate patients with reflux symptoms and a negative endoscopy, who well respond to PPIs with MII-pH. METHODS: We enrolled 312 patients with GERD symptoms and negative endoscopy: 144 reported well-controlled symptoms after 8-week PPIs and 155 were non-responders. Symptom relief was evaluated with GERD Impact Scale and visual analog scale score. All patients underwent MII-pH off-therapy. Thirteen patients were excluded from analysis. Patients were grouped as follows: non-erosive reflux disease (NERD; increased acid exposure time, AET); hypersensitive esophagus (HE; normal AET, positive symptom association, SI/SAP); MII-pH-/PPI+ (normal AET, negative SI/SAP) in the responder group; MII-pH-/PPI- in non-responders. KEY RESULTS: MII-pH in PPI responders (symptom relief during PPI therapy > 75%) showed: 79/144 NERD (54.9%); 37/144 HE (25.7%); 28/144 MII-pH-/PPI+ (19.4%). MII-pH-/PPI+ patients reported the same symptom relief when compared with NERD and HE. In non-responder (symptom relief during PPI therapy < 50%) group, 27/155 patients were NERD (17.4%); 53/155 were HE (34.2%); 75/155 were MII-pH-/PPI- (48.4%). NERD diagnosis was significantly higher in responder group (p < 0.01). CONCLUSIONS & INFERENCES: In a substantial subgroup of patients responding to PPI with typical reflux symptoms, the diagnosis of GERD cannot be confirmed with pH-impedance monitoring. Proton pump inhibitor response and presence of typical symptoms are thus not reliable predictors of the diagnosis and antireflux surgery should always be preceded by reflux monitoring.


Asunto(s)
Monitorización del pH Esofágico , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/tratamiento farmacológico , Inhibidores de la Bomba de Protones/uso terapéutico , Adulto , Impedancia Eléctrica , Femenino , Reflujo Gastroesofágico/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
5.
Q J Nucl Med Mol Imaging ; 54(6): 689-97, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20639808

RESUMEN

AIM: Kinase inhibitors have been proposed as novel therapeutic agents in different forms of solid tumours. The Food and Drug Administration (FDA) approved the use of Sorafenib, an oral multikinase inhibitor, for advanced renal carcinoma and unresectable hepatocellular carcinoma. On-going studies are investigating the efficacy of Sorafenib in other solid tumours such as melanoma and non-small cells lung carcinoma and pre-clinical models showed the efficacy of treatment with Sorafenib in murine models of renal cells carcinoma, breast cancer, colon carcinoma and melanoma. To our knowledge, Sorafenib has never been employed in human lymphoma. The aim of the present study was to assess the efficacy of Sorafenib in murine models of human anaplastic large cells lymphoma (ALCL) and Hodgkin lymphoma (HD). METHODS: Sorafenib cytotoxicity was assessed in vitro and growth inhibition (IC50) was calculated. Cells were assayed for Caspase-3 to measure apoptosis. Human ALCL and HD xenografts in NOD/SCID mice were monitored by small animal positron emission tomography (PET) and computed tomography (CT) over time. Tumour bearing animals were randomly selected to receive treatment with Sorafenib or no treatment. Pathology was available in all cases. RESULTS: Sorafenib efficacy on cells proliferation and apoptosis (IC50: HD=0.0343 mg/L; ALCL=0.319 mg/L) was confirmed in vitro. Caspase-3 production showed a dose-dependent trend reaching significantly higher values for 0.046 mg/L and 0.465 mg/L drug concentrations in both cell lines. In vivo experiments showed a progressive increase of tumour lesions metabolism and dimensions regardless treatment. CONCLUSION: Sorafenib showed a good cytotoxic effect in vitro especially on human HD cell line, but these findings were not confirmed in vivo. The strong discrepancy between in vitro and in vivo results suggests that further studies are needed to better acknowledge the biodistribution and metabolism of Sorafenib in NOD/SCID mice. Factors influencing drug availability at tumour site or differences in the downstream pathways may be responsible for the scarse effect of treatment.


Asunto(s)
Bencenosulfonatos/uso terapéutico , Fluorodesoxiglucosa F18 , Linfoma/diagnóstico por imagen , Linfoma/tratamiento farmacológico , Tomografía de Emisión de Positrones/veterinaria , Piridinas/uso terapéutico , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Evaluación Preclínica de Medicamentos/métodos , Evaluación Preclínica de Medicamentos/veterinaria , Humanos , Ratones , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Pronóstico , Radiofármacos , Sorafenib , Resultado del Tratamiento
6.
Q J Nucl Med Mol Imaging ; 54(1): 16-23, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20168283

RESUMEN

Neuroendocrine tumours (NET) diagnosis has represented a major challenge in the past decades. The introduction of somatostatin receptor scintigraphy in the diagnostic work-up led to a significant improvement of accuracy. However with the advent of positron emission tomography (PET) that presents a higher spatial resolution as compared to the gamma camera and an array of different radiotracers, it is now possible to image NET with an even higher accuracy. In fact, PET imaging of NET is a rapidly evolving field closely connected to the development of novel beta-emitting radiopharmaceuticals. NET can be easily visualized on PET scans using an array of both metabolic and receptor-based tracers. [18F]DOPA and [68Ga]DOTA-peptides (DOTA-TOC, DOTA-NOC, DOTA-TATE) are very promising to image well differentiated NET and were reported to be superior to other imaging modalities (computed tomography [CT], somatostatin receptor scintigraphy). On the contrary, the role of [18F]FDG is limited in well differentiated NET, due to their low glucose metabolism and growth rate, while it still can provide valuable information in less differentiated tumours. On-going studies are investigating the potential role of new imaging agents (bombesin, GLP-1, CCK) that specifically bind to receptors expressed on NET cells.


Asunto(s)
Tumores Neuroendocrinos/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Humanos , Tumores Neuroendocrinos/metabolismo , Radiofármacos/metabolismo
7.
Radiol Med ; 114(1): 152-67, 2009 Feb.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-19082783

RESUMEN

In recent years, new technologies have become available for imaging small animals. The use of animal models in basic and preclinical sciences, for example, offers the possibility of testing diagnostic markers and drugs, which is becoming crucial in the success and timeliness of research and is allowing a more efficient approach in defining study objectives and providing many advantages for both clinical research and the pharmaceutical industry. The use of these instruments offers data that are more predictive of the distribution and efficacy of a compound. The mouse, in particular, has become a key animal model system for studying human disease. It offers the possibility of manipulating its genome and producing accurate models for many human disorders, thus resulting in significant progress in understanding pathologenic mechanisms. In neurobiology, the possibility of simulating neurodegenerative diseases has enabled the development and validation of new treatment strategies based on gene therapy or cell grafting. Noninvasive imaging in small living animal models has gained increasing importance in preclinical research, itself becoming an independent specialty. The aim of this article is to review the characteristics of these systems and illustrate their main applications.


Asunto(s)
Investigación Biomédica , Imagen por Resonancia Magnética/métodos , Microrradiografía , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Ultrasonografía/métodos , Experimentación Animal , Animales , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Industria Farmacéutica , Vivienda para Animales , Humanos , Imagenología Tridimensional , Ratones , Microrradiografía/métodos , Ratas , Sensibilidad y Especificidad
8.
Cancer Biomark ; 4(4-5): 277-84, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18957716

RESUMEN

With increasing application of positron-emission tomography (PET) imaging, familiarity with the applications of PET in genitourinary oncology, especially prostate-cancer (PCa) imaging, becomes important. PET studies provide functional information using radiolabeled tracers, with fluoro-dexoxy-glucose (FDG) being the most commonly used. Nevertheless FDG has limitations for evaluation of PCa patients and therefore alternative tracers are being investigated. To date, the best results have been obtained with 11C-choline and 11C-acetate PET, which seem to demonstrate similar values in this field. We review the current role of PET in PCa patients based on data published in the literature as well as our own experience. Most studies of PET imaging of PCa address three goals: a) detecting primary PCa; b) staging PCa; and c) assessing PCa recurrence. From available results, routine clinical use of 11C-choline PET cannot be recommended for detecting and staging primary PCa. At present, the only clinical indication for imaging PCa with 11C-choline-PET is evaluation of suspected recurrence after treatment.


Asunto(s)
Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Acetatos , Anciano , Biopsia , Radioisótopos de Carbono , Colina , Fluorodesoxiglucosa F18 , Humanos , Masculino , Estadificación de Neoplasias , Radiofármacos , Tomografía Computarizada por Rayos X
9.
Ann Oncol ; 18(3): 551-5, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17158773

RESUMEN

BACKGROUND: Recent guidelines do not recommend antithrombotic prophylaxis (AP) to prevent catheter-related thrombosis in cancer patients with a central line. PATIENTS AND METHODS: This study assessed the management of central lines in cancer patients, current attitude towards AP, catheter-related and systemic venous thromboses, and survival. RESULTS: Of 1410 patients enrolled, 1390 were seen at least once in the 6-month median follow-up. Continuous AP, mainly low-dose warfarin, was given to 451 (32.4%); they were older, with a more frequent history of venous thromboembolism (VTE), and more advanced cancer. There was no difference in catheter-related thrombosis in patients given AP or not (2.8% and 2.2%, odds ratio 1.29, 95% confidence interval 0.64-2.6). The median time to first catheter-related complication was 120 days. Systemic VTE including deep and superficial thromboses and pulmonary embolism, were less frequent with AP (4% versus 8.2%, P = 0.005). Mortality was also lower (25% versus 44%, P = 0.0001). Multiple logistic regression analysis found only advanced cancer and no AP significantly associated with mortality. No major bleeding was recorded with AP. CONCLUSIONS: Current AP schedules do not appear to prevent catheter-related thrombosis. Systemic VTE and mortality, however, appeared lower after prophylaxis.


Asunto(s)
Cateterismo Venoso Central/efectos adversos , Catéteres de Permanencia/efectos adversos , Fibrinolíticos/uso terapéutico , Neoplasias/complicaciones , Embolia Pulmonar/prevención & control , Trombosis de la Vena/prevención & control , Warfarina/uso terapéutico , Cateterismo Venoso Central/instrumentación , Femenino , Humanos , Italia/epidemiología , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Oportunidad Relativa , Estudios Prospectivos , Embolia Pulmonar/etiología , Embolia Pulmonar/mortalidad , Medición de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Trombosis de la Vena/etiología , Trombosis de la Vena/mortalidad
10.
Radiol Med ; 111(8): 1146-55, 2006 Dec.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-17171520

RESUMEN

PURPOSE: Metastatic cancers of unknown primary origin are characterised by a poor prognosis, with a survival rate from diagnosis of approximately 12 months. Conventional radiological imaging allows detection of 20%-27% of primary cancers, whereas the detection rate with positron emission tomography (PET) is 24%-40%. The aim of this study was to assess the role of 18F-fluorodeoxyglucose (FDG) PET/computed tomography (CT) in the identification of occult primary cancers. MATERIALS AND METHODS: The study population consisted of 38 consecutive patients with histologically proven metastatic disease and negative or nonconclusive conventional diagnostic procedures. All patients were studied by 18F-FDG PET performed according to the standard procedure (6 h of fasting, intravenous injection of 370 MBq 18F-FDG, and image acquisition with a PET/CT scanner for 4 min per bed position). RESULTS: 18F-FDG-PET/CT detected the occult primary cancer in 20 cases (53%), showing higher sensitivity than that reported for any other imaging modality, including PET. CONCLUSIONS: The encouraging results, if validated by larger series, support the use of PET/CT in patients with carcinoma of unknown primary origin and negative conventional imaging results.


Asunto(s)
Carcinoma/diagnóstico , Carcinoma/secundario , Fluorodesoxiglucosa F18 , Neoplasias Primarias Desconocidas/diagnóstico , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Primarias Desconocidas/diagnóstico por imagen , Pronóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Biomed Pharmacother ; 60(9): 593-606, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16978824

RESUMEN

This paper aims at discussing the utility of 18F-FDG PET/CT in the evaluation of paediatric solid extracranial tumours. Following a brief discussion of the basic principles and methodology of PET/CT system, it reviews the main characteristics of the tumours that can be visualised with 18F-FDG PET and presents examples of cases where the combined use of 18F-FDG PET/CT fusion imaging helped in the management of patients. It will also discuss the physiologic biodistribution of 18F-FDG, outlining the normal variants in the paediatric patients that may lead to misinterpretation.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Niño , Humanos , Interpretación de Imagen Asistida por Computador , Linfoma/diagnóstico por imagen , Neuroblastoma/diagnóstico por imagen , Osteosarcoma/diagnóstico por imagen , Distribución Tisular
13.
Ann Oncol ; 17 Suppl 7: vii10-4, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16760270

RESUMEN

BACKGROUND: Tamoxifen, for many years the 'gold standard' in the adjuvant setting for the management of endocrine sensitive early breast cancer, is associated with an increased risk of endometrial cancer and other life-threatening events. Moreover, many women relapse during or after tamoxifen therapy due to the development of resistance. This provided the rationale for a switching trial with anastrozole, the updated results of which are reported here. PATIENTS AND METHODS: This trial investigated the efficacy of switching to anastrozole for women already receiving tamoxifen. After 2-3 years of tamoxifen treatment, postmenopausal, node-positive, ER-positive patients were randomized to receive either anastrozole 1 mg/day or to continue tamoxifen, 20 mg/day, giving a total duration of 5-years treatment. The primary end point was disease-free survival and secondary endpoints were event-free survival, overall survival and safety. RESULTS: A total of 448 patients were enrolled. At a median follow-up time of 64 months (range 12-93), 63 events had been reported in the tamoxifen group compared with 39 in the anastrozole group [HR 0.57 (95% CI 0.38-0.85) P = 0.005]. Relapse-free and overall survival were also longer in the anastrozole group [HR 0.56 (95% CI 0.35-0.89) P = 0.01 and 0.56 (95% CI 0.28-1.15) P = 0.1]. However, the latter difference was not statistically significant. Overall more patients in the anastrozole group experienced at least one adverse event (209 versus 151: P = 0.000). However, numbers of patients experiencing serious adverse events were comparable (37 versus 40, respectively: P = 0.7). CONCLUSIONS: Switching to anastrozole after the first 2-3 years of treatment was confirmed to improve event-free and relapse-free survival of postmenopausal, node-positive, ER-positive early breast cancer patients already receiving adjuvant tamoxifen.


Asunto(s)
Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Nitrilos/uso terapéutico , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Tamoxifeno/uso terapéutico , Triazoles/uso terapéutico , Anastrozol , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/metabolismo , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Nitrilos/efectos adversos , Posmenopausia , Receptores de Estrógenos/biosíntesis , Moduladores Selectivos de los Receptores de Estrógeno/efectos adversos , Tamoxifeno/efectos adversos , Triazoles/efectos adversos
14.
Biomed Imaging Interv J ; 2(4): e60, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21614340

RESUMEN

Positron emission tomography (PET) is a non-invasive imaging modality, which is clinically widely used both for diagnosis and accessing therapy response in oncology, cardiology and neurology.Fusing PET and CT images in a single dataset would be useful for physicians who could read the functional and the anatomical aspects of a disease in a single shot.The use of fusion software has been replaced in the last few years by integrated PET/CT systems, which combine a PET and a CT scanner in the same gantry. CT images have the double function to correct PET images for attenuation and can fuse with PET for a better visualization and localization of lesions. The use of CT for attenuation correction yields several advantages in terms of accuracy and patient comfort, but can also introduce several artefacts on PET-corrected images.PET/CT image artefacts are due primarily to metallic implants, respiratory motion, use of contrast media and image truncation. This paper reviews different types artefacts and their correction methods.PET/CT improves image quality and image accuracy. However, to avoid possible pitfalls the simultaneous display of both Computed Tomography Attenuation Corrected (CTAC) and non corrected PET images, side by side with CT images is strongly recommended.

15.
Eur J Nucl Med Mol Imaging ; 32(5): 589-92, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15726356

RESUMEN

PURPOSE: Metastatic cancer of unknown primary origin is a syndrome characterised by a poor prognosis, with a typical survival rate from diagnosis of no longer than 1 year. Only 20-27% of primary tumours are identified by conventional radiological imaging. By contrast, it has been reported that 18F-fluorodeoxyglucose positron emission tomography (FDG PET) allows the identification of 24-40% of otherwise unrecognised primary tumours. To our knowledge, the studies on this topic have been conducted using 18F-FDG PET imaging alone. The aim of this study was to evaluate the potential additional diagnostic role of fused 18F-FDG PET-CT imaging for the detection of metastatic occult primary tumours. METHODS: The study population consisted of 21 consecutive patients with biopsy-proven metastatic disease and negative conventional diagnostic procedures. Each patient underwent a PET scan, carried out according to a standard procedure (6 h of fasting, i.v. injection of 370 MBq of 18F-FDG and image acquisition with a dedicated PET-CT scanner for 4 min per bed position). RESULTS: 18F-FDG PET-CT detected the occult primary tumour in 12 patients (57% of cases), providing a detection rate higher than that reported with any other imaging modality, including conventional 18F-FDG PET. CONCLUSION: The favourable results of this study need to be confirmed in larger patient populations with long-term follow-up.


Asunto(s)
Adenocarcinoma/diagnóstico , Adenocarcinoma/secundario , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/secundario , Aumento de la Imagen/métodos , Neoplasias Primarias Desconocidas/diagnóstico , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Técnica de Sustracción
16.
Panminerva Med ; 47(3): 187-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16462726

RESUMEN

AIM: The aim of the present study was to assess the accuracy of an hybrid PET/CT scanner in the evaluation of newly diagnosed parotid masses, comparing the results with those reported in the literature with using PET scanners only. METHODS: The potential role of 18F-FDG PET/CT in distinguishing benign from malignant parotid masses in 14 consecutive patients was investigated. All patients were preoperatively evaluated by means of ultrasound (US), US-guided fine needle aspiration (FNA) cytology, computed tomography (CT) scan, magnetic resonance imaging (MRI) and 18F-FDG PET/CT. For To interpreting FDG PET findings, the right to left parotid (R/L) SUV max ratio was calculated in a group of 54 patients without evidence of parotideal disease (mean+/-SD = 1+/-0.2; range = 0.8-1.2); considering the R/L SUV max ratio, focal or diffuse uptakes <0.8 or >1.2 were considered as potentially pathological. RESULTS: Imaging data were compared with surgical and histopathological findings. At FDG PET/CT, 9 false positive cases were found (8 Warthin's tumours, 1 pleomorphic adenoma), 1 false negative (acinar cell carcinoma), 4 true negative (1 Warthin's tumour, 1 pleomorphic adenoma, 1 lymph epithelial cyst, 1 parotid inflammation) whereas there was no case of true positive. The global accuracy of FGD PET/CT was rather low = at 29%. CONCLUSIONS: In agreement with other preliminary reports in which the FDG PET without CT fusion imaging was used, in our experience 18F-FDG PET/CT did not prove to play a significant role in differential diagnosis (benign vs malignant) of parotid masses. Further studies collecting larger groups of patients are needed to further elucidate this observation.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de la Parótida/diagnóstico , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Neoplasias de la Parótida/patología
18.
Anticancer Drugs ; 11(8): 645-8, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11081457

RESUMEN

This paper is a report on a case of gastric carcinoma of diffuse type in a young female patient aged 38. The patient was still asymptomatic at hospital admission, her only pathological sign being the finding of malignant cells of indeterminate origin at a routine Pap-test examination. Subsequent investigations showed the presence of a poorly differentiated gastric carcinoma, with metastatic diffusion to uterus, ovaries and peritoneum. Only a few cases of gastric carcinomas without cervical localization, detected by Pap-test, are reported in literature. A few other cases with cervical localization have been described. The aim of this work is to point out that a Pap-test smear may reveal the presence of extragenital tumors still unappreciated.


Asunto(s)
Adenocarcinoma/secundario , Carcinoma/diagnóstico , Carcinoma/patología , Neoplasias Ováricas/secundario , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Neoplasias Uterinas/secundario , Frotis Vaginal , Adulto , Femenino , Humanos
19.
Haematologica ; 84(7): 604-7, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10406901

RESUMEN

BACKGROUND AND OBJECTIVE: Therapy of both Hodgkin's disease (HD) and aggressive non-Hodgkin's lymphoma (NHL) with mediastinal presentation at the time of diagnosis is frequently followed by radiological detection of residual masses. Computed tomography (CT) scanning is generally unable to detect the differences between tumor tissue and fibrosis. Gallium-67-citrate single photon emission ((67)GaSPECT) can potentially differentiate residual active tumor tissue from fibrosis. DESIGN AND METHODS: Seventy-five patients with HD or aggressive NHL presenting mediastinal involvement (64% with a bulky mass) were studied with CT and (67)GaSPECT at the end of combined modality therapy (chemo- and radiation therapy). RESULTS: After treatment, 3/3 (100%) patients with positive (67)GaSPECT and negative CT scan relapsed while only 1/18 (6%) patients with both negative (67)GaSPECT and CT scan did so. At the same time, 54 patients had a positive restaging CT scan (abnormal mass < 10% of size of initial mass). Of these patients, 13 had a positive (67)GaSPECT, 10 of whom (77%) relapsed; 41 had a negative (67)GaSPECT of whom 5 (12%) relapsed. The 4-year actuarial relapse-free survival rate was 90% for those with negative scans compared with 23% for gallium-positive patients (p < 0.000000). INTERPRETATION AND CONCLUSIONS: In lymphoma patients with mediastinal involvement, (67)GaSPECT should be considered, at least in patients who are CT positive, the imaging technique of choice for monitoring and differentiating the nature of any residual masses.


Asunto(s)
Linfoma/diagnóstico , Neoplasias del Mediastino/diagnóstico , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Galio , Humanos , Linfoma/tratamiento farmacológico , Linfoma/fisiopatología , Masculino , Neoplasias del Mediastino/fisiopatología , Neoplasias del Mediastino/terapia , Persona de Mediana Edad , Análisis de Supervivencia , Tomografía Computarizada de Emisión de Fotón Único
20.
Minerva Cardioangiol ; 45(6): 259-66, 1997 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-9432566

RESUMEN

BACKGROUND: Clinical diagnosis of deep venous thrombosis (DVT) of the leg is unreliable. An accurate diagnosis is important for therapeutic decision since anticoagulant treatment, though potentially dangerous, is useless in case of a false positive diagnosis, whereas a false negative diagnosis may lead to withdrawal of an extremely necessary anticoagulation. Contrast venography is still recognized as the gold standard method for the diagnosis of DVT, but in recent years a variety of accurate non-invasive methods has been developed. The ultrasound compression sonography (CUS) is considered a simple non invasive test highly sensitive and specific for proximal DVT in symptomatic outpatients, though non adequately sensitive and specific for isolated calf DVT. Plasma D-dimer levels (DD, fibrin degradation products) have a high negative predictive value for DVT. The aim of this study, performed in outpatients with suspected leg DVT, was to validate, versus venography, a non-invasive, easy to perform and fast diagnostic procedure based on a combination of CUS and D-dimer test. End points of the procedure were: confirmation or exclusion of proximal DVT; suspicion of isolated calf DVT in which case the test would be repeated in a few days to detect any possible proximalization of thrombosis. MATERIALS AND METHODS: Sixty-eight consecutive outpatients, 37 male, with clinically suspected first episode of leg DVT were eligible and examined with CUS, DD test and venography. RESULTS: The results showed that the diagnostic procedure under examination has a high sensibility and specificity for DVT. CONCLUSIONS: It can thus be recommended as routine diagnostic procedure in symptomatic outpatients with suspected DVT reserving venography special cases only.


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno/análisis , Tromboflebitis/diagnóstico por imagen , Instituciones de Atención Ambulatoria , Femenino , Humanos , Masculino , Flebografía , Valor Predictivo de las Pruebas , Ultrasonografía/métodos
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