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1.
Eur J Nucl Med Mol Imaging ; 51(4): 1185-1193, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38038755

RESUMEN

PURPOSE: To assess early tumor response with quantitated SPECT/CT and to correlate it with clinical outcome in metastatic castration-resistant prostate cancer (mCRPC) patients treated with 177Lutetium-PSMA I&T therapy. METHODS: Single-center, observational study, part of the prospective Swiss national cancer registry study investigating the safety and efficacy of [177Lu]Lu-PSMA I&T (EKNZ: 2021-01271) in mCRPC patients treated with at least two cycles of [177Lu]Lu-PSMA I&T 6-weekly. After the first and second cycle quantitated SPECT/CT (Symbia Intevo, Siemens) was acquired 48 h after injection (three fields of view from head to thigh, 5 s/frame) and reconstructed using xQuant® (48i, 1 s, 10-mm Gauss). Image analysis: The PSMA-positive total tumor volumes (TTV) were semi-automatically delineated using a SUV threshold of 3 with MIMencore® (version 7.1.3, Medical Image Merge Software Inc.). Changes in TTV, highest tumor SUVmax, and total tumor SUVmean between cycles 1 and 2 were calculated and grouped into a) stable or decrease and b) increase. Serum PSA levels were assessed at each therapy cycle and at follow-up until progression or death. Changes in TTV, PSA, SUVmax, and SUVmean were correlated with PSA-progression-free survival (PSA-PFS) and the overall survival (OS) using the Kaplan-Meier methodology (log-rank test). RESULTS: Between 07/2020 and 04/2022, 111 patients were screened and 73 finally included in the data analysis. The median follow-up was 8.9 months (range 1.4-26.6 months). Stable or decreased TTV at cycle 2 was associated with longer OS (hazard ratio (HR) 0.28, 95% confidence interval (CI) 0.09-0.86, p < 0.01). Similar, stable, or decreased PSA was associated with longer OS (HR 0.21; CI 0.07-0.62, p < 0.01) and PSA-PFS (HR 0.34; 95% CI 0.16-0.72, p < 0.01). Combining TTV and PSA will result in an augmented prognostic value for OS (HR 0.09; CI 0.01-0.63; p < 0.01) and for PSA-PFS (HR 0.11; CI 0.02-0.68; p < 0.01). A reduction of SUVmax or SUVmean was not prognostically relevant, neither for OS (p 0.88 and 0.7) nor for PSA-PFS (p 0.73 and 0.62, respectively). CONCLUSION: Six weeks after initiating [177Lu]Lu-PSMA I&T, TTV and serum PSA appear to be good prognosticators for OS. Combined together, TTV + PSA change demonstrates augmented prognostic value and can better predict PSA-PFS. Larger studies using TTV change prospectively as an early-response biomarker are warranted for implementing management change towards a more personalized clinical practice.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración , Urea/análogos & derivados , Masculino , Humanos , Neoplasias de la Próstata Resistentes a la Castración/diagnóstico por imagen , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Suiza , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Resultado del Tratamiento , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Lutecio/uso terapéutico , Dipéptidos/uso terapéutico , Estudios Retrospectivos
2.
Pituitary ; 24(6): 878-886, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34155554

RESUMEN

PURPOSE: 11-C-methionine (MET)-positron emission tomography (PET) as an adjunct to magnetic resonance imaging (MRI) has been proposed as a suitable molecular imaging modality for localizing pituitary adenomas in Cushing's disease. 18-F-Fluoroethyl-L-tyrosine (FET)-PET, which is more widely available has not yet been reported in this context. METHODS: Retrospective double-center cohort study on 15 patients who underwent transsphenoidal surgery for biochemically proven Cushing's disease between 2011 and 2019. Preoperative MET-PET/MRI and/or FET-PET/MRI were compared with intraoperative and histopathological examinations using the Mann Whitney U test and the Fisher's Exact test, along with positive predictive value calculations. RESULTS: Fifteen patients were included, with a mean age of 47.2 (18-69) years. Six patients received either a MET-PET/MRI or a FET-PET/MRI and 3 patients both exams, respectively. 67% of the tumors were detected by MRI (MET-PET-group [56%]; FET-PET-group [78%]). All tumors were microadenomas with a mean adenoma volume of 0.19 cm3 (0.02-0.78), all of which displayed a circumscribed pathological FET- and/or MET-uptake. FET-PET/MRI results positively correlated with the localization of the tumor confirmed intraoperatively and histopathologically in all cases, resulting in a sensitivity and specificity of FET-PET/MRI for tumor localization of 100% (95% CI 66.37-100%). One MET-PET/MRI suggested a localization contralateral to the expected spot. The sensitivity and specificity of MET-PET for tumor localization hence was 89% (95% CI 51.75-99.72%). CONCLUSIONS: Preoperative hybrid FET-PET/MRI and MET-PET/MRI have a high predictive value in localizing corticotroph adenoma for selective adenomectomy in Cushing's disease.


Asunto(s)
Adenoma , Neoplasias Encefálicas , Adenoma/diagnóstico por imagen , Adenoma/cirugía , Estudios de Cohortes , Humanos , Imagen por Resonancia Magnética , Metionina , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Estudios Retrospectivos , Tirosina
3.
Eur J Nucl Med Mol Imaging ; 44(10): 1671-1678, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28631036

RESUMEN

PURPOSE: Radium Ra 223 dichloride (radium-223, Xofigo®) is the first targeted alpha therapy for patients with castration-resistant prostate cancer and symptomatic bone metastases. Radium-223 provides a new treatment option for this setting, but also necessitates a new treatment management approach. We provide straightforward and practical recommendations for European nuclear medicine centres to optimize radium-223 service provision. METHODS: An independent research consultancy agency observed radium-223 procedures and conducted interviews with all key staff members involved in radium-223 treatment delivery in 11 nuclear medicine centres across six countries (Germany, Italy, the Netherlands, Spain, Switzerland and the UK) experienced in administering radium-223. The findings were collated and discussed at a meeting of experts from these centres, during which key consensus recommendations were defined. RESULTS: The recommendations cover centre organization and preparation; patient referral; radium-223 ordering, preparation and disposal; radium-223 treatment delivery/administration; and patient experience. Guidance includes structured coordination and communication within centres and multidisciplinary teams, focusing on sharing best practice to provide high-quality, patient-centred care throughout the treatment pathway. CONCLUSIONS: These expert recommendations are intended to complement existing management guidelines. Sharing best practice and experience will help nuclear medicine centres to optimize radium-223 service provision and improve patient care.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Radio (Elemento)/uso terapéutico , Testimonio de Experto , Humanos , Masculino , Metástasis de la Neoplasia , Satisfacción del Paciente , Selección de Paciente
4.
Onkologie ; 32(12): 724-30, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20016233

RESUMEN

BACKGROUND: Only responding patients benefit from preoperative therapy for locally advanced esophageal carcinoma. Early detection of non-responders may avoid futile treatment and delayed surgery. PATIENTS AND METHODS: In a multi-center phase ll trial, patients with resectable, locally advanced esophageal carcinoma were treated with 2 cycles of induction chemotherapy followed by chemoradiotherapy (CRT) and surgery. Positron emission tomography with 2[fluorine-18]fluoro-2-deoxy-d-glucose (FDG-PET) was performed at baseline and after induction chemotherapy. The metabolic response was correlated with tumor regression grade (TRG). A decrease in FDG tumor uptake of less than 40% was prospectively hypothesized as a predictor for histopathological non-response (TRG > 2) after CRT. RESULTS: 45 patients were included. The median decrease in FDG tumor uptake after chemotherapy correlated well with TRG after completion of CRT (p = 0.021). For an individual patient, less than 40% decrease in FDG tumor uptake after induction chemotherapy predicted histopathological non-response after completion of CRT, with a sensitivity of 68% and a specificity of 52% (positive predictive value 58%, negative predictive value 63%). CONCLUSIONS: Metabolic response correlated with histopathology after preoperative therapy. However, FDG-PET did not predict non-response after induction chemotherapy with sufficient clinical accuracy to justify withdrawal of subsequent CRT and selection of patients to proceed directly to surgery.


Asunto(s)
Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/terapia , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Pronóstico , Estudios Prospectivos , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Suiza , Resultado del Tratamiento
5.
Nucl Med Commun ; 28(10): 789-97, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17728609

RESUMEN

OBJECTIVE: To determine parameters of perfusion, distribution coefficient, and glucose metabolism as part of the tumour-specific micromilieu of breast cancer and compare them with corresponding values in normal breast tissue. METHODS: H2(15)O PET and 18F-FDG PET were performed on 10 patients with advanced invasive ductal carcinomas of the breast. Perfusion, distribution coefficient, and glucose metabolism and standardized uptake were quantified and analysed. RESULTS: Mean values based on the regions of interest were 59.2+/-43.9 ml x min(-1) x 100 g(-1) (perfusion), 0.58+/-0.26 ml x g(-1) (distribution coefficient), 7.76+/-6.10 (standardized uptake), and 5.4+/-2.5 mg x min(-1) x 100 g(-1) (glucose metabolism). The corresponding values for normal breast tissue were 22.1+/-13.2 ml x min x 100 g(-1) (perfusion), 0.16+/-0.05 ml x g(-1) (distribution coefficient), 0.33+/-0.07 (standardized uptake), and 0.18+/-0.08 mg x min x 100 g(-1) (glucose metabolism). For each tumour-normal tissue parameter pair, the mean values were significantly higher in tumours than normal breast tissue. Region-of-interest and pixel-wise correlation analysis revealed a positive association between glucose metabolism and distribution coefficient and glucose metabolism and perfusion for 7/10 tumours investigated. CONCLUSIONS: H2(15)O PET and 18F-FDG PET were able to differentiate breast cancer and normal breast tissue. The pixel-wise analysis revealed information about the heterogeneity of tumour fine structure in perfusion, distribution coefficient, and glucose metabolism, which may provide important guidelines for improving individual treatment.


Asunto(s)
Velocidad del Flujo Sanguíneo , Neoplasias de la Mama/fisiopatología , Fluorodesoxiglucosa F18/farmacocinética , Glucosa/metabolismo , Neovascularización Patológica/fisiopatología , Radioisótopos de Oxígeno/farmacocinética , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Tasa de Depuración Metabólica , Persona de Mediana Edad , Neovascularización Patológica/diagnóstico por imagen , Distribución Tisular , Agua/metabolismo
6.
J Am Coll Cardiol ; 45(9): 1505-12, 2005 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-15862426

RESUMEN

OBJECTIVES: We sought to assess prospectively whether patients with normal coronary angiograms but with impaired myocardial blood flow (MBF) increases to cold pressor testing (CPT) are at increased risk for cardiovascular events. BACKGROUND: Invasive angiographic assessments of coronary vasomotor function have demonstrated an impairment of endothelium-related coronary flow increases to independently predict future cardiovascular events. It is unknown whether noninvasive positron emission tomography (PET)-measured MBF alterations to sympathetic stimulation with CPT are associated with the risk of developing cardiovascular events. METHODS: A total of 72 patients (44 men, 28 women, age 58 +/- 8 years) referred for diagnostic cardiac catheterization were studied. Myocardial blood flow was measured in absolute units with (13)N-ammonia using PET, at baseline and during CPT in each patient. Cardiovascular events (cardiovascular death, acute coronary syndrome, myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass grafting, ischemic stroke, or peripheral revascularization) were assessed as clinical outcome parameters over a mean follow-up period of 66 +/- 8 months. Patients were assigned to three groups: group 1, patients with >/=40% increase in MBF (%DeltaMBF), n = 22; group 2, patients with >0 and <40% increases in MBF, n = 32; and group 3, patients with decreases in MBF (

Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Infarto del Miocardio/epidemiología , Tomografía de Emisión de Positrones , Amoníaco , Velocidad del Flujo Sanguíneo , California/epidemiología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/fisiopatología , Circulación Coronaria/fisiología , Femenino , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/mortalidad , Radioisótopos de Nitrógeno , Tomografía de Emisión de Positrones/efectos adversos , Estudios Prospectivos , Radiofármacos , Análisis de Supervivencia , Suiza/epidemiología
7.
Circulation ; 110(9): 1069-75, 2004 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-15313940

RESUMEN

BACKGROUND: The goal of this study was to examine a possible association between systemic microinflammation, as reflected by C-reactive protein (CRP) serum levels, and coronary vasomotion in patients with coronary risk factors but with angiographically normal coronary arteries. METHODS AND RESULTS: Coronary vasomotor function was studied in response to cold pressor testing (CPT) in 71 patients with normal angiograms. In all patients, CPT-induced changes in epicardial luminal area (LA; mm2) were assessed with quantitative angiography. Within 20 days, myocardial blood flow (MBF) responses to CPT were measured (mL x g(-1) x min(-1)) noninvasively with 13N-ammonia and PET imaging. The CPT-induced mean changes in LA and in MBF in patients with elevated CRP (> or =0.5 mg/dL) were significantly impaired compared with patients presenting with CRP levels within normal range (<0.5 mg/dL) (DeltaLA, -1.09+/-0.86 versus 0.45+/-0.63 mm2; DeltaMBF, 0.06+/-0.18 versus 0.44+/-0.31 mL x g(-1) x min(-1); P<0.0001, respectively). Coronary LA changes and MBF responses to CPT were inversely correlated with CRP serum levels (r=-0.84 and r=-0.63; P<0.0001). Lastly, regression analysis revealed a significant correlation between the changes in LA and MBF during CPT for patients with elevated CRP levels and those for patients with normal CRP levels (r=0.56 and r=0.66; P<0.001). CONCLUSIONS: These findings suggest a direct association between systemic microinflammation and altered coronary vasomotor function of both the epicardial conductance and the arteriolar resistance vessels.


Asunto(s)
Proteína C-Reactiva/análisis , Enfermedad Coronaria/complicaciones , Vasos Coronarios/fisiopatología , Inflamación/complicaciones , Sistema Vasomotor/fisiopatología , Anciano , Arteriolas/fisiopatología , Biomarcadores , Frío , Comorbilidad , Angiografía Coronaria , Circulación Coronaria , Enfermedad Coronaria/sangre , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/fisiopatología , Endotelio Vascular/fisiopatología , Femenino , Humanos , Inflamación/sangre , Masculino , Persona de Mediana Edad , Factores de Riesgo , Resistencia Vascular , Vasoconstricción
8.
J Am Coll Cardiol ; 42(5): 814-22, 2003 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-12957426

RESUMEN

OBJECTIVES: We sought to determine whether abnormal myocardial blood flow (MBF) responses to the cold pressor test (CPT) in patients with various risk factors may involve different mechanisms that could lead to varying responses of short- and long-term administration of antioxidants. BACKGROUND: There is a growing body of evidence that increased vascular production of reactive oxygen species markedly reduces the bioavailability of endothelium-derived nitric oxide, leading to impaired vasodilator function. It is unknown whether increased oxidative stress is the prevalent mechanism underlying endothelial dysfunction in patients with different coronary risk factors. METHODS: Fifty patients with normal coronary angiograms were studied. The MBF responses to CPT was determined by means of positron emission tomography before and after intravenous infusion of 3 g vitamin C or saline (placebo), as well as after 3 months and 2 years of 2 g vitamin C or placebo supplementation daily. RESULTS: In hypertensive patients, the change in MBF (DeltaMBF) was not modified significantly by short-term vitamin C administration challenges (0.20 +/- 0.20 ml/g/min; p = NS) but was significantly increased after three months and two years of treatment with vitamin C versus baseline (0.58 +/- 0.27 and 0.63 +/- 0.17 vs. 0.14 +/- 0.18 ml/g/min; both p < or = 0.001). In smokers, DeltaMBF in response to CPT was significantly increased after short-term vitamin C infusion and long-term vitamin C treatment (0.52 +/- 0.10, 0.54 +/- 0.13, 0.50 +/- 0.07 vs. -0.08 +/- 0.10 ml/g/min; all p < or = 0.001). In hypercholesterolemic patients, no improvement in DeltaMBF during CPT was observed after short- and long-term vitamin C treatment (0.05 +/- 0.14, 0.08 +/- 0.18, 0.02 +/- 0.19 vs. 0.08 +/- 0.16 ml/g/min; p = NS). The CPT-induced DeltaMBF in hypertensive patients and smokers after follow-up was significant as compared with placebo and control subjects (p < or = 0.001). CONCLUSIONS: The present study revealed marked heterogeneous responses in MBF changes to short- and long-term vitamin C treatment in patients with various risk factors, which highlights the quite complex nature underlying abnormal coronary vasomotion.


Asunto(s)
Antioxidantes/uso terapéutico , Ácido Ascórbico/uso terapéutico , Circulación Coronaria/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Hipercolesterolemia/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Fumar/tratamiento farmacológico , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Angiografía Coronaria , Enfermedad Coronaria/etiología , Enfermedad Coronaria/prevención & control , Vasos Coronarios/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Hipercolesterolemia/complicaciones , Hipercolesterolemia/metabolismo , Hipercolesterolemia/fisiopatología , Hipertensión/complicaciones , Hipertensión/metabolismo , Hipertensión/fisiopatología , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/efectos adversos , Especies Reactivas de Oxígeno/metabolismo , Factores de Riesgo , Fumar/efectos adversos , Fumar/metabolismo , Fumar/fisiopatología , Tomografía Computarizada de Emisión , Resultado del Tratamiento
9.
Arterioscler Thromb Vasc Biol ; 23(3): 495-501, 2003 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-12615687

RESUMEN

OBJECTIVE: We aimed to evaluate prospectively whether patients with normal coronary angiogram but abnormal epicardial vasoreactivity to cold pressor test (CPT) are at increased risk for cardiovascular events. METHODS AND RESULTS: Vasoreactivity in response to CPT and dilation of epicardial arteries to intracoronary application of nitroglycerin were assessed quantitatively (percent change of luminal area, DeltaLA%) in 130 patients with normal coronary angiograms. Cardiovascular events (cardiovascular death, acute coronary syndrome, myocardial infarction, percutaneous transluminal coronary angioplasty, coronary bypass grafting, ischemic stroke, or peripheral revascularization) were assessed as clinical outcome parameters over a mean follow-up period of 45+/-9 months. Based on their vascular responses to CPT, patients were assigned into the following 3 groups: group 1, patients with normal vasodilator response (DeltaLA >0%; n=37); group 2, patients with moderate vasoconstrictor response (DeltaLA between 0% and -15%; n=42); and group 3, patients with severe vasoconstrictor response (DeltaLA < or =-15%; n=51). Although patients from groups 2 and 3 had significantly increased vasoconstrictor response to CPT (group 2, DeltaLA -6+/-3% and group 3, DeltaLA -24+/-6% versus group 1, DeltaLA 11+/-9%; P< or =0.0001), they showed normal endothelial-independent epicardial vasodilation to intracoronary application of nitroglycerin similar to patients from group 1 (DeltaLA 39+/-16% and 34+/-14% versus 41+/-14%; P=NS, respectively). During follow-up, none of the patients from group 1 developed cardiac events. However, 7 cardiovascular events occurred in group 2 and 30 occurred in group 3 in 4 and 22 patients, respectively (P< or =0.0001, univariate by log-rank test). After adjustment for known risk factors for coronary artery disease, impaired epicardial coronary vasoreactivity to CPT remained significantly associated with the risk of developing cardiovascular events (P=0.040, multivariate by Cox regression model). CONCLUSIONS: In patients with normal coronary angiogram, abnormal vasoreactivity of epicardial coronary arteries in response to sympathetic stimulation is associated with the risk of developing cardiovascular events.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Vasoespasmo Coronario/complicaciones , Vasoespasmo Coronario/diagnóstico por imagen , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/etiología , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Angiografía Coronaria , Vasoespasmo Coronario/fisiopatología , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Sistema Nervioso Simpático/fisiopatología
10.
Eur J Radiol ; 54(2): 264-70, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15837408

RESUMEN

PURPOSE: We evaluated the diagnostic accuracy of magnetic resonance imaging (MRI) and positron emission tomography (PET) for detection of liver metastases in malignant melanoma. MATERIAL AND METHODS: Thirty-five patients with 39 combined unenhanced MRI and fluorine-18 deoxyglucose (F-18 FDG) PET scans were prospectively studied. In discordant imaging findings final diagnosis was proven by clinical follow-up >6 months and demonstration of progressive liver metastases by at least one imaging method. Sensitivities and specificities were compared and the influence of lesion size and melanin content on diagnostic accuracy was determined. RESULTS: MRI and PET were concordantly negative for presence and number of liver metastases in 28 patients and positive in four patients. PET and MRI were false positive in one patient each. In one patient MRI showed a single metastases not seen by PET and in one patient MRI demonstrated more metastases at the first examination. In follow-up investigations MRI revealed more metastases than PET in both patients. The sensitivities for lesion detection were 47% (16/34) for PET and 100% for MRI. Lesion detectability by PET was related to lesion size (P < 0.0001) but not to melanin content. CONCLUSION: MRI is more sensitive in the detection of liver metastases in patients with malignant melanoma. Small lesions are easily missed by PET, while melanin content does not influence detectability by PET.


Asunto(s)
Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética/métodos , Melanoma/diagnóstico , Melanoma/secundario , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste/administración & dosificación , Fluorodesoxiglucosa F18 , Estudios de Seguimiento , Humanos , Aumento de la Imagen/métodos , Hígado/diagnóstico por imagen , Hígado/patología , Melaninas/metabolismo , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
J Nucl Med ; 43(5): 610-6, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11994522

RESUMEN

UNLABELLED: The aim of this prospective phase II study was to evaluate the tumor response of neuroendocrine tumors to high-dose targeted irradiation with 7.4 GBq/m(2) of the radiolabeled somatostatin analog (90)Y-1,4,7,10-tetra-azacyclododecan-4,7,10-tricarboxy-methyl-1-yl-acetyl-D-Phe-Tyr(3)-octreotide (DOTATOC). In addition, we investigated the clinical benefit of (90)Y-DOTATOC regarding the malignant carcinoid syndrome and tumor-associated pain. METHODS: Thirty-nine patients (mean age, 55 y) with progressive neuroendocrine gastroenteropancreatic and bronchial tumors were included. The treatment consisted of 4 equal intravenous injections of a total of 7.4 GBq/m(2) (90)Y-DOTATOC, administered at intervals of 6 wk. After each treatment cycle, a standardized clinical benefit assessment using the National Cancer Institute grading criteria (NCI-CTC) was performed. RESULTS: The objective response rate according to World Health Organization (WHO) criteria was 23%. For endocrine pancreatic tumors (13 patients), the objective response rate was 38%. Complete remissions were found in 5% (2/39), partial remissions in 18% (7/39), stable disease in 69% (27/39), and progressive disease in 8% (3/39). A significant reduction of clinical symptoms could be found in 83% of patients with diarrhea, in 46% of patients with flush, in 63% of patients with wheezing, and in 75% of patients with pellagra. The overall clinical benefit was 63%. All responses (both clinical benefit and WHO response) were ongoing for the duration of follow-up (median, 6 mo; range, 2-12 mo). Side effects were grade 3 or 4 (NCI-CTC) lymphocytopenia in 23%, grade 3 anemia in 3%, and grade 2 renal insufficiency in 3%. CONCLUSION: High-dose targeted radiotherapy with 7.4 GBq/m(2) (90)Y-DOTATOC is a well-tolerated treatment for neuroendocrine tumors, with remarkable clinical benefit and objective response.


Asunto(s)
Tumores Neuroendocrinos/radioterapia , Octreótido/análogos & derivados , Octreótido/uso terapéutico , Radiofármacos/uso terapéutico , Radioisótopos de Itrio/uso terapéutico , Tumor Carcinoide/radioterapia , Humanos , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/mortalidad , Dolor Intratable/tratamiento farmacológico , Cintigrafía , Radioisótopos de Itrio/efectos adversos
12.
J Nucl Med ; 45(3): 419-28, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15001682

RESUMEN

UNLABELLED: The aims of this study were to determine whether responses in myocardial blood flow (MBF) to the cold pressor testing (CPT) method noninvasively with PET correlate with an established and validated index of flow-dependent coronary vasomotion on quantitative angiography. METHODS: Fifty-six patients (57 +/- 6 y; 16 with hypertension, 10 with hypercholesterolemia, 8 smokers, and 22 without coronary risk factors) with normal coronary angiograms were studied. Biplanar end-diastolic images of a selected proximal segment of the left anterior descending artery (LAD) (n = 27) or left circumflex artery (LCx) (n = 29) were evaluated with quantitative coronary angiography in order to determine the CPT-induced changes of epicardial luminal area (LA, mm(2)). Within 20 d of coronary angiography, MBF in the LAD, LCx, and right coronary artery territory was measured with (13)N-ammonia and PET at baseline and during CPT. RESULTS: CPT induced on both study days comparable percent changes in the rate x pressure product (%DeltaRPP, 37% +/- 13% and 40% +/- 17%; P = not significant [NS]). For the entire study group, the epicardial LA decreased from 5.07 +/- 1.02 to 4.88 +/- 1.04 mm(2) (DeltaLA, -0.20 +/- 0.89 mm(2)) or by -2.19% +/- 17%, while MBF in the corresponding epicardial vessel segment increased from 0.76 +/- 0.16 to 1.03 +/- 0.33 mL x min(-1) x g(-1) (DeltaMBF, 0.27 +/- 0.25 mL x min(-1) x g(-1)) or 36% +/- 31% (P

Asunto(s)
Frío , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Pericardio/diagnóstico por imagen , Tomografía Computarizada de Emisión/métodos , Velocidad del Flujo Sanguíneo , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Endotelio Vascular/diagnóstico por imagen , Endotelio Vascular/fisiopatología , Femenino , Humanos , Hipercolesterolemia , Hipertensión , Masculino , Persona de Mediana Edad , Pericardio/fisiopatología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto , Vasoconstricción
13.
Mol Imaging Biol ; 6(3): 160-71, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15193250

RESUMEN

PURPOSE: To determine the prevalence of viable myocardium in patients with ischemic cardiomyopathy and, to evaluate the value of three-dimensional (3-D) fusion imaging of myocardial scintigraphic and angiographic data to assign coronary artery lesions to the corresponding viable and nonviable myocardial territory. PROCEDURES: In 105 patients, the combination of perfusion and metabolic imaging with (201)thallium ((201)TI) single-photon emission computed tomography (SPECT) and 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) positron emission tomography (PET) determined viability in dysfunctional myocardium. In addition, the value of 3-D scintigraphic fusion imaging was assessed in these patients. RESULTS: Based on the presence of viable dysfunctional myocardium, 54% of patients with ischemic cardiomyopathy may be considered for coronary revascularization. In 31 of 105 patients, the 3-D fusion imaging was estimated to be helpful in the diagnostic and interpretative process. CONCLUSION: In patients with end-stage coronary artery disease scintigraphic imaging is most important in the decision-making process. Three-dimensional fusion imaging may add important information in approximately 30% of these patients.


Asunto(s)
Cardiomiopatías/diagnóstico por imagen , Angiografía Coronaria/métodos , Isquemia Miocárdica/diagnóstico por imagen , Tomografía Computarizada de Emisión/métodos , Anciano , Femenino , Fluorodesoxiglucosa F18 , Corazón/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Miocardio/citología , Pronóstico , Talio
14.
Neurosci Lett ; 335(2): 79-82, 2002 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-12459503

RESUMEN

Cerebral positron emission tomography (PET) in children often requires sedation. This study evaluated sedation-associated effects on cerebral glucose metabolism in 30 children with severe myoclonic epilepsy as investigated by cerebral (18)F-fluorodeoxyglucose (FDG)-PET. Prior to the PET acquisition, 24 children underwent propofol sedation. Pixel-based t-statistics were calculated using statistical parametric mapping (SPM99) for comparisons of the patients' PET scans with both a healthy adult control group and an age-matched child intra-group control. In both analyses, statistically significant hypometabolic areas were found in the medial parieto-occipital cortex bilaterally, including the lingual gyrus, cuneus, posterior cingulate and middle occipital gyrus in all sedated children. All these localizations correlated in a covariate analysis with the injected dose of propofol (P<0.01, corrected). The bilateral parieto-occipital hypometabolism is likely to be a sedation-specific effect and should be taken into account when evaluating cerebral FDG-PET scans in sedated children.


Asunto(s)
Anticonvulsivantes/farmacología , Corteza Cerebral/efectos de los fármacos , Epilepsias Mioclónicas/metabolismo , Glucosa/metabolismo , Propofol/farmacología , Tomografía Computarizada de Emisión , Adolescente , Adulto , Anciano , Algoritmos , Mapeo Encefálico , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/metabolismo , Niño , Preescolar , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Occipital/metabolismo , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/metabolismo
15.
J Nucl Med ; 55(4): 546-50, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24566001

RESUMEN

UNLABELLED: Low-grade gliomas (LGGs) may harbor malignant foci, which are characterized by increased tumor cellularity and angiogenesis. We used diffusion-weighted MR imaging (apparent diffusion coefficient [ADC]) and PET with the amino acid O-(2-(18)F-fluorethyl)-L-tyrosine ((18)F-FET) to search for focal changes of diffusion (ADC) and amino acid uptake and to investigate whether focal changes in these parameters colocalize within LGGs. METHODS: We retrospectively selected 18 patients with nonenhancing LGG. All patients had undergone (18)F-FET PET and MR imaging for preoperative evaluation or for therapy monitoring in recurrent or progressive LGG. Region-of-interest analysis was performed to compare (18)F-FET uptake and ADC values in areas with focal intratumoral maximum metabolic activity and diffusion restriction and between tumor and normal brain. (18)F-FET uptake was normalized to the mean cerebellar uptake (ratio). ADC values were also compared with the (18)F-FET uptake on a voxel-by-voxel basis across the whole tumor. RESULTS: The mean focal maximum (mean ± SD, 1.69 ± 0.85) and global (18)F-FET uptake in tumors (1.14 ± 0.41) exceeded that of normal cortex (0.85 ± 0.09) and cerebrospinal fluid (0.82 ± 0.20). ADC values in the area with most restricted diffusion (1.07 ± 0.22 × 10(-3) mm(2)/s) and in the whole tumor (1.38 ± 0.27 × 10(-3) mm(2)/s) were in the range between normal cortex (0.73 ± 0.06 × 10(-3) mm(2)/s) and cerebrospinal fluid (2.84 ± 0.09 × 10(-3) mm(2)/s). (18)F-FET uptake did not correlate with corresponding (colocalizing) ADC values, either in the area with focal maximum metabolic activity or in the area with most restricted diffusion or in the whole tumor. CONCLUSION: There is no congruency between (18)F-FET uptake and diffusivity in nonenhancing LGG. Diffusion restriction in these tumors most likely represents changes in brain and tumor cell densities as well as alteration of water distribution and is probably not directly correlated with the density of tumor cells.


Asunto(s)
Aminoácidos/metabolismo , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Imagen de Difusión por Resonancia Magnética/métodos , Glioma/diagnóstico por imagen , Glioma/patología , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Neoplasias Cerebelosas/diagnóstico por imagen , Cerebelo/diagnóstico por imagen , Difusión , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Radiofármacos/líquido cefalorraquídeo , Estudios Retrospectivos , Tirosina/análogos & derivados , Tirosina/líquido cefalorraquídeo
17.
Clin Nucl Med ; 37(1): e1-3, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22157049

RESUMEN

PURPOSE: Positron emission tomography (PET) with radiolabeled amino acids provides information on biopsy target and chemotherapy response in patients with low-grade gliomas (LGG). In this article, we addressed whether PET with F-18 choline (CHO) detects increased metabolism in F-18 fluoroethyltyrosine (FET)-negative LGG patients. METHODS: Six LGG patients with nongadolinium-enhancing (magnetic resonance) FET-negative LGG were imaged with CHO PET. Regions of interest were positioned over tumor and contralateral brain. Uptake of FET and CHO was quantified as count ratio of tumor to contralateral brain. RESULTS: The mean FET uptake ratio for FET-negative LGG was 0.95 ± 0.03 (mean ± standard deviation). Five tumors did not show increased uptake ratios for CHO (0.96 ± 0.12). Slightly increased CHO uptake was found in 1 patient (1.24), which, however, was not associated with tumor visualization. CONCLUSIONS: Amino acid and choline uptake appear to behave similar in nongadolinium-enhancing LGG. For clinical purposes, CHO PET is not superior to FET PET.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Colina/análogos & derivados , Glioma/metabolismo , Tomografía de Emisión de Positrones/métodos , Tirosina/análogos & derivados , Adulto , Neoplasias Encefálicas/diagnóstico por imagen , Colina/farmacocinética , Reacciones Falso Negativas , Femenino , Glioma/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tirosina/farmacocinética
18.
Eur J Nucl Med Mol Imaging ; 32(6): 674-81, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15747154

RESUMEN

PURPOSE: This study was performed to investigate the value of( 18)F-fluorodeoxyglucose positron emission tomography ([(18)F]FDG-PET) in the diagnosis of large-vessel vasculitis and the assessment of activity and extent of disease. METHODS: Twenty-six consecutive patients (21 females, 5 males; median age - years, range 17-86 years) with giant cell arteritis or Takayasu's arteritis were examined with [(18)F]FDG-PET. Follow-up scans were performed in four patients. Twenty-six age- and gender-matched controls (21 females, 5 males; median age 71 years, range 17-86 years) were included. The severity of large-vessel [(18)F]FDG uptake was visually graded using a four-point scale. C-reactive protein (CRP) and the erythrocyte sedimentation rate (ESR) were measured and correlated with [(18)F]FDG-PET results by logistic regression. RESULTS: [(18)F]FDG-PET revealed pathological findings in 18 of 26 patients. Three scans were categorised as grade I, 12 as grade II and 3 as grade III arteritis. Visual grade was significantly correlated with both CRP and ESR levels (p=0.002 and 0.007 respectively; grade I: CRP 4.0 mg/l, ESR 6 mm/h; grade II: CRP 37 mg/l, ESR 46 mm/h; grade III: CRP 172 mg/l, ESR 90 mm/h). Overall sensitivity was 60% (95% CI 40.6-77.3%), specificity 99.8% (95% CI 89.1-100%), positive predictive value 99.7% (95% CI 77-100%), negative predictive value 67.9% (95% CI 49.8-80.9%) and accuracy 78.6% (95% CI 65.6-88.4%). In patients presenting with a CRP <12 mg/l or an ESR <12 mm/h, logistic regression revealed a sensitivity of less than 50%. In patients with high CRP/ESR levels, sensitivity was 95.5%/80.7%. CONCLUSION: [(18)F]FDG-PET is highly effective in assessing the activity and the extent of large-vessel vasculitis. Visual grading was validated as representing the severity of inflammation. Its use is simple and provides high specificity, while high sensitivity is achieved by scanning in the state of active inflammation.


Asunto(s)
Fluorodesoxiglucosa F18 , Arteritis de Células Gigantes/clasificación , Arteritis de Células Gigantes/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Arteritis de Takayasu/clasificación , Arteritis de Takayasu/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Método Simple Ciego
19.
J Magn Reson Imaging ; 15(4): 456-61, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11948835

RESUMEN

PURPOSE: To improve analysis of cerebral white matter (WM) in fluoro-deoxy-glucose positron emission tomography (PET) images. MATERIALS AND METHODS: A multimodality analysis technique (segmented MRI and registered Talairach-transformed PET [SMART-PET]) was used for quantitative assessment of WM metabolism. Data processing included Talairach transformation of three-dimensional magnetic resonance imaging (MRI) and subsequent automated segmentation and coregistration to normalized PET images. Color model transformations were used for combined display: the hue saturation value color model was regarded as a three-dimensional data matrix, integrating quantitative voxel data of both modalities. The technique was applied in normal subjects and in patients suffering from different WM diseases. Regional analysis was performed to classify metabolic impairment on a five-point scale. RESULTS: Using SMART-PET, a considerable gain in image contrast for WM was achieved in all cases. In the normal subjects, WM metabolism was shown to be homogeneously unimpaired. Sum scores of regional analysis revealed metabolic WM changes in all patients. Extent of WM hypometabolism exceeded the extent of the lesions as delineated by MRI signal changes. CONCLUSION: The potential of the method for further elucidation of the role of WM diseases in brain dysfunction in patients is discussed.


Asunto(s)
Encéfalo/anatomía & histología , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada de Emisión/métodos , Encefalopatías/diagnóstico , Color , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos
20.
Clin Positron Imaging ; 2(4): 191-196, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-14516529

RESUMEN

The objective of this study was to test the clinical practicability of a 3D-cardiac-positron emission tomography(PET) procedure. During preoperative viability diagnostics of the myocardium with fluorine-18-fluorodeoxyglucose(18F-FDG)PET, comparative recordings were made in 2D (ECAT Exact) and 3D Mode (Quest). Ten patients (2 women, 8 men, ages 34-72 years) with coronary artery disease and a known myocardial infarction in the history were examined. Both examinations were made on the same day following single FDG injection. In 9 of the 10 cases, 3 independent examiners arrived at the same diagnoses from the 2D and 3D recordings, whereby only one-third the activity used for 2D exposures was required for 3D acquisition. In one case, the 3D recording showed no accumulation around the anterior wall near the apex, in spite of demonstrated, albeit limited, viability in the 2D mode. The cause of this discrepant finding is assumed to lie in equipment/uptake and patient-related differences in the test configuration. In summary, 3D acquisition offers a promising alternative to 2D recordings in the viability diagnostics of the myocardium based on a considerable reduction in radiation exposure for patients and personnel, as well as reduction in the costs for radiopharmaceuticals. Further evaluation of the method in broader studies would appear necessary.

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