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1.
AJNR Am J Neuroradiol ; 35(10): 2013-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24948497

RESUMO

BACKGROUND AND PURPOSE: Systematic investigations of the distinguishing imaging features between spinal hyperplastic hematopoietic bone marrow and bone metastasis have not been reported, to our knowledge. The purpose of this study was to determine the distinguishing imaging features of the 2 entities. MATERIALS AND METHODS: We retrospectively reviewed the radiologic images of 8 consecutive male patients (age range, 52-78 years; mean, 64 years) with suspected spinal metastasis on MR imaging and FDG-PET, which was later confirmed as hyperplastic hematopoietic bone marrow. MR imaging, FDG-PET, CT, and bone scintigraphy images were qualitatively and/or quantitatively evaluated. Imaging findings in 24 patients with spinal metastasis were compared, and differences were statistically analyzed. RESULTS: All 8 vertebral hyperplastic hematopoietic bone marrow lesions were hypointense on T1- and T2-weighted images; lesions contiguous with the adjacent vertebra were significantly more often seen in hyperplastic hematopoietic bone marrow than in metastasis (P = .035). T2 signal intensity of the lesion was significantly different between the 2 entities (P = .033). FDG-PET showed slightly higher uptake in all hyperplastic hematopoietic bone marrow lesions; their maximum standard uptake value was significantly lower than that of metastatic lesions (P = .037). CT attenuation of hyperplastic hematopoietic bone marrow was equal to or slightly higher than that of adjacent normal-appearing vertebra; the CT appearances of hyperplastic hematopoietic bone marrow and metastasis were significantly different (P < .01). Bone scintigraphy showed normal uptake for all vertebrae with hyperplastic hematopoietic bone marrow; the uptake was significantly different from that of metastasis (P < .01). CONCLUSIONS: If a lesion was isointense to hyperintense to normal-appearing marrow on MR imaging or had a maximum standard uptake value of >3.6, the lesion was considered metastatic. A normal appearance on CT or bone scintigraphy excluded metastasis.


Assuntos
Doenças da Medula Óssea/diagnóstico , Medula Óssea/patologia , Neoplasias da Coluna Vertebral/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Humanos , Hiperplasia/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Cintilografia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
2.
Dis Esophagus ; 27(1): 36-41, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23384275

RESUMO

Radiofrequency ablation (RFA) is increasingly being used for the treatment of intrathoracic malignancies. Although RFA has been found to be promising in the treatment of lung metastases from some types of neoplasms, little is known concerning its clinical significance in the treatment of pulmonary metastasis from esophageal squamous cell carcinoma (ESCC). This retrospective study evaluated the feasibility, safety, and effectiveness of computed tomography-guided RFA for pulmonary metastasis from ESCC. A series of 10 ESCC patients with 17 pulmonary tumors were included. Correct placement of the ablation device into the target tumor proved to be feasible in all tumors (100%). The mean visual analog scale score, with values that ranged from 0 (no pain) to 10 (worst pain possible), was 1. This suggested that this procedure was well tolerated. No procedure-related deaths occurred. A pneumothorax needing drainage was a major complication in two patients. Local control of ablated tumor lasting for at least 1 year was achieved in 10 (83%) of 12 assessable tumors. Although locoregional recurrences developed in two tumors, these lesions could be recontrolled by repeat treatment with RFA. Three patients died of recurrent disease. The predicted 1- and 2-year overall survival rates after lung RFA were 77.8% and 62.2%, respectively. Percutaneous computed tomography-guided RFA yielded relatively high levels of local control in patients with pulmonary metastases from ESCC and was associated with an acceptable level of complications. It was concluded that a prospective study will be necessary to evaluate the effectiveness of a combination of systemic therapy and RFA for ESCC lung metastases.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Ablação por Cateter/métodos , Neoplasias Esofágicas/patologia , Neoplasias Pulmonares/cirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/secundário , Estudos de Coortes , Neoplasias Esofágicas/cirurgia , Esofagectomia , Estudos de Viabilidade , Humanos , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Cirurgia Assistida por Computador , Tomografia Computadorizada por Raios X , Resultado do Tratamento
3.
Clin Radiol ; 65(8): 609-15, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20599062

RESUMO

AIM: To investigate the effect of a double-exposure dual-energy subtraction (DES) technique on the diagnostic performance of radiologists detecting small pulmonary nodules on flat-panel detector (FPD) chest radiographs. MATERIALS AND METHODS: Using FPD radiography 41 sets of chest radiographs were obtained from 26 patients with pulmonary nodules measuring

Assuntos
Competência Clínica/normas , Neoplasias Pulmonares/diagnóstico por imagem , Radioterapia (Especialidade)/normas , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Curva ROC , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/instrumentação , Sensibilidade e Especificidade , Técnica de Subtração/instrumentação
4.
Acta Radiol ; 49(6): 693-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18568563

RESUMO

BACKGROUND: Although gross tumor volume (GTV) at the primary site can predict local control of head-and-neck squamous cell carcinoma (SCC) in patients who are treated with organ-preservation therapy, GTV assessment does not eliminate substantial interobserver variation. PURPOSE: To evaluate whether F-18-fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) fused imaging provides additional information for GTV assessment. MATERIAL AND METHODS: We obtained FDG-PET/CT fused images on 20 patients with head-and-neck SCC. All had undergone preoperative conventional workup, including contrast-enhanced CT and magnetic resonance imaging (MRI). The GTV of the primary tumors was designed by two independent observers who used routine clinical data. Observer A was a radiologist and observer B a radiation oncologist. GTV1 and GTV2 were designed without and with FDG-PET/CT, respectively. For geometric interobserver comparison, we calculated the concordance rate as the ratio of the intersection (AxB) of the GTVs to their union (AxB). Intermethod (GTV1 vs. GTV2) and interobserver (A vs. B) differences in the GTVs were assessed by Bland-Altman analysis and the Spearman rank-correlation test. The interobserver concordance rates for GTV1 and GTV2 were compared using a two-tailed paired-samples t test. RESULTS: On FDG-PET/CT, all primary tumors were visualized. There was no systemic trend for a volume difference between GTV1 and GTV2. Although the 95% limits of agreement were wider for interobserver than intermethod differences, the 95% limits of interobserver agreement were narrower for GTV2 than GTV1. The mean interobserver concordance rate for GTV2 was higher than for GTV1 (54.5% vs. 39.1%, P=0.0002). CONCLUSION: FDG-PET/CT is a useful modality for consistent GTV assessment, which should not be used as a single modality but rather to obtain supplemental information in patients with head-and-neck SCC.


Assuntos
Carcinoma de Células Escamosas/patologia , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/patologia , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral , Adulto , Idoso , Feminino , Humanos , Imageamento Tridimensional , Laringe/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Boca/diagnóstico por imagem , Variações Dependentes do Observador , Faringe/diagnóstico por imagem , Compostos Radiofarmacêuticos , Estudos Retrospectivos
5.
Acta Radiol ; 48(8): 900-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17924221

RESUMO

BACKGROUND: Although intraarterial chemotherapy has been used to treat head and neck cancers, some cases have shown poor response. If we can predict the response to this therapy on MRI, individual treatment plans may be altered to the most appropriate form of treatment. PURPOSE: To evaluate whether MRI can predict the histological response to preoperative chemoirradiation in patients with cancer of the mouth. MATERIAL AND METHODS: This study comprised of 29 consecutive patients with 30 oral cancers. All patients underwent tumor resection after intraarterial infusion chemotherapy and conformal radiotherapy. We compared the margin of the tumor, the presence of bone invasion, tumor area, and volume on pre- and post-treatment MRI with histological responses. RESULTS: Eighteen lesions showed an excellent response, nine exhibited a good response, and three a poor response. Only the tumor area on pretreatment T1-weighted images and the tumor area and volume on pretreatment enhanced T1-weighted images were significantly correlated with the histological response (P = 0.039, 0.008, and 0.016, respectively); smaller cancers showed better responses. The other factors were not significantly correlated with the histological responses. CONCLUSION: MRI parameters, excluding initial tumor area and volume, were not predictive of the histological response of oral tumors to preoperative treatment.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Neoplasias Bucais/patologia , Neoplasias Bucais/terapia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Feminino , Humanos , Infusões Intra-Arteriais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Radioterapia Adjuvante , Radioterapia Conformacional
6.
Diabetes ; 50(6): 1397-401, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375341

RESUMO

In many patients with human immunodeficiency virus (HIV) treated with HIV protease inhibitors, a complication develops that resembles abdominal obesity syndrome, with insulin resistance and glucose intolerance that, in some cases, progresses to diabetes. In this study, we tested the hypothesis that indinavir, an HIV-protease inhibitor, directly induces insulin resistance of glucose transport in skeletal muscle. Rat epitrochlearis muscles were incubated with a maximally effective insulin concentration (12 nmol/l) and 0, 1, 5, 20, or 40 micromol/l indinavir for 4 h. In control muscles, insulin increased 3-O-[(3)H]methyl-D-glucose (3MG) transport from 0.15 +/- 0.03 to 1.10 +/- 0.05 micromol. ml(-)(1). 10 min(-)(1). Incubation of muscles with 5 micromol/l indinavir reduced the insulin-stimulated increase in 3MG transport by 40%, whereas 20 micromol/l indinavir reduced the insulin-stimulated increase in 3MG transport by 58%. Indinavir induced a similar reduction in maximally insulin-stimulated 3MG transport in the soleus muscle. The increase in glucose transport activity induced by stimulating epitrochlearis muscles to contract was also markedly reduced by indinavir. The insulin-stimulated increase in cell-surface GLUT4, assessed using the 2-N-4-(1-azi-2,2,2-trifluoroethyl)benzoyl-1,3-bis-[2-(3)H] (D-mannose-4-yloxy)-2-propylamine exofacial photolabeling technique, was reduced by approximately 70% in the presence of 20 micromol/l indinavir. Insulin stimulation of phosphatidylinositol 3-kinase activity and phosphorylation of protein kinase B were not decreased by indinavir. These results provide evidence that indinavir inhibits the translocation or intrinsic activity of GLUT4 rather than insulin signaling.


Assuntos
Inibidores da Protease de HIV/farmacologia , Indinavir/farmacologia , Insulina/farmacologia , Proteínas de Transporte de Monossacarídeos/metabolismo , Contração Muscular/fisiologia , Proteínas Musculares , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Proteínas Serina-Treonina Quinases , Animais , Membrana Celular/metabolismo , Transportador de Glucose Tipo 4 , Técnicas In Vitro , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Wistar
7.
Radiology ; 207(2): 423-30, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9577491

RESUMO

PURPOSE: To evaluate the long-term results of irradiation alone or of embolization with or without irradiation in patients with dural carotid cavernous fistulas (DCCFs). MATERIALS AND METHODS: Between 1984 and 1996, symptomatic DCCFs in 26 patients were treated by using irradiation alone (protocol 1, n = 12) before April 1988 and by using embolization as an initial treatment (protocol 2, n = 14) during and after April 1988. When angiography showed no improvement after embolization, irradiation was added (n = 6). On the basis of drainage flow speed, DCCFs were classified as fast, medium, or slow. RESULTS: With irradiation alone, all six patients with slow- to medium-type DCCFs had cure with a mean follow-up of 62 months. Four of six patients with fast-type DCCFs had cure or improvement, but the remaining two had no change. In the embolization group, irradiation was added in six patients with fast-type DCCFs. With a mean follow-up of 24 months, four of the six patients had cures, one had improvement, and one had no clinical change. Those who underwent protocol 2 had cures significantly earlier than those who underwent protocol 1 (P < .05). CONCLUSION: Conventional radiation therapy resulted in cure of DCCFs in nine (75%) of the 12 patients and in improvement of signs and symptoms in one (8%). Fast-type DCCFs may not always be improved. Radiation therapy may be useful in DCCFs after embolization.


Assuntos
Fístula Arteriovenosa/radioterapia , Artérias Carótidas/anormalidades , Seio Cavernoso/anormalidades , Embolização Terapêutica , Adulto , Idoso , Angiografia Digital , Fístula Arteriovenosa/terapia , Velocidade do Fluxo Sanguíneo/fisiologia , Protocolos Clínicos , Terapia Combinada , Meios de Contraste , Dura-Máter/irrigação sanguínea , Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Fluxo Sanguíneo Regional/fisiologia , Técnicas Estereotáxicas
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