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1.
Br J Radiol ; 83(994): 841-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20846983

RESUMO

Accurate determination of tumour size in lung adenocarcinoma with bronchoalveolar features (BAC) is important for the determination of TNM (tumour, nodes, metastasis) scores used in staging, prognosis and therapy response assessment. However, tumour sizes derived using lung window (LW) CT or soft-tissue/mediastinal window (MW) CT often give different results. This study examines which measurement correlates best with actual tumour size and which best identifies advanced disease. This retrospective study included 43 BAC patients who underwent surgical resection with mediastinal lymphadenectomy <4 weeks post CT scan. The largest unidimensional tumour diameter on each CT window was compared with actual histopathological tumour size (HP). LW, MW and HP size measurements and a recently described CT parameter - the modified tumour shadow disappearance rate (mTDR) = (1 - [MW/LW]) - were then used to determine which parameter best discriminated between the presence or absence of advanced disease. There was no difference between HP and LW sizes, but MW significantly underestimated HP size (p<0.0001). Unlike MW (p = 0.01) and mTDR (p = 0.001), neither HP (p = 0.14) nor LW (p = 0.10) distinguished between patients with or without advanced disease. On receiver operating characteristic (ROC) analysis at a cut-off of ≤0.13, the sensitivity and specificity of mTDR for detecting advanced disease were 69% and 89%, respectively. In patients with tumours ≤3 cm, only mTDR remained a significant predictor of advanced disease (p = 0.017), with best cut-off at ≤0.20, giving a sensitivity and specificity of 71% and 94%, respectively. MW better predicts advanced disease than LW and might also need to be recorded for RECIST (response evaluation criteria in solid tumours) assessment for T staging of BAC; however, mTDR appears to be an even better predictor and should also be used.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Idoso , Feminino , Humanos , Metástase Linfática , Masculino , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons/métodos , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral
2.
Br J Cancer ; 98(12): 1922-8, 2008 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-18506141

RESUMO

Twenty per cent of sentinel lymph node (SLN)-positive melanoma patients have positive non-SLN lymph nodes in completion lymph node dissection (CLND). We investigated SLN tumour load, non-sentinel positivity and disease-free survival (DFS) to assess whether certain patients could be spared CLND. Sentinel lymph node biopsy was performed on 392 patients between 1999 and 2005. Median observation period was 38.8 months. Sentinel lymph node tumour load did not predict non-SLN positivity: 30.8% of patients with SLN macrometastases (> or =2 mm) and 16.4% with micrometastases (< or =2 mm) had non-SLN positivity (P=0.09). Tumour recurrences after positive SLNs were more than twice as frequent for SLN macrometastases (51.3%) than for micrometastases (24.6%) (P=0.005). For patients with SLN micrometastases, the DFS analysis was worse (P=0.003) when comparing those with positive non-SLNs (60% recurrences) to those without (17.6% recurrences). This difference did not translate into significant differences in DFS: patients with SLN micrometastasis, either with (P=0.022) or without additional positive non-SLNs (P<0.0001), fared worse than patients with tumour-free SLNs. The 2-mm cutoff for SLN tumour load accurately predicts differences in DFS. Non-SLN positivity in CLND, however, cannot be predicted. Therefore, contrary to other studies, no recommendations concerning discontinuation of CLND based on SLN tumour load can be deduced.


Assuntos
Metástase Linfática , Melanoma/patologia , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Melanoma/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/cirurgia
6.
Radiologe ; 44(11): 1060-7, 2004 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-15517141

RESUMO

PURPOSE: First results of PET/CT in Hodgkin's disease (HD) and aggressive non-Hodgkin's lymphoma (NHL) are reported. PATIENTS AND METHODS: From March 2001 to August 2004 822 PET/CT were performed at our clinic in lymphoma patients for primary staging, restaging after therapy, and diagnosis of recurrence. For coregistration non contrast-enhanced low-dose CT were used. RESULTS: Due to the exact anatomic localization of (18)F-FDG accumulating lesions equivocal or false positive PET findings are avoided. In comparison to contrast enhanced CT, PET/CT has a higher sensitivity and specificity in patients with HD and aggressive NHL. Integration of PET/CT in treatment planning of radiation therapy optimizes the field volume. CONCLUSION: Even in the initial phase of clinical evaluation, PET/CT has proven useful in staging and restaging of lymphoma. The exact anatomic localization of the PET findings is essential for a precise report, for treatment planning of radiation therapy, and for planning surgical biopsy.


Assuntos
Doença de Hodgkin/diagnóstico , Aumento da Imagem/instrumentação , Processamento de Imagem Assistida por Computador/instrumentação , Linfoma/diagnóstico , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Criança , Pré-Escolar , Desenho de Equipamento , Feminino , Fluordesoxiglucose F18 , Seguimentos , Doença de Hodgkin/patologia , Doença de Hodgkin/terapia , Humanos , Linfoma/patologia , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Sensibilidade e Especificidade , Resultado do Tratamento
7.
Br J Dermatol ; 150(4): 677-86, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15099363

RESUMO

BACKGROUND: Baseline staging in patients with primary cutaneous malignant melanoma (MM) is routine, but the diagnostic accuracy and the impact on clinical outcome are still unclear. OBJECTIVES: To evaluate the sensitivity and specificity of baseline staging in the early detection of regional lymph node metastases or distant metastases in patients with MM. METHODS: One hundred consecutive patients with MM of Breslow's tumour thickness over 1.0 mm were enrolled. All patients had an extensive baseline staging including physical examination, ultrasound (US) of the abdomen and regional lymph nodes, chest X-ray, whole-body positron emission tomography (PET) and sentinel lymph node biopsy. The sensitivity and specificity of detection of macroscopic or microscopic metastases in the regional lymph nodes or at distant sites were calculated for each method. RESULTS: Sentinel lymph node biopsy was positive in 26 patients. US detected two of 26 histologically tumour-positive sentinel nodes (sensitivity 8%, specificity 88%) and PET two of 26 (sensitivity 8%; specificity 100%). There were three lymph node metastases with a diameter > 4 mm. All of them were found suspect at physical examination. Two of them were detectable with US, two with PET, and all were identified with either US or PET. Nine patients had suspect findings at distant sites, which were all false positive on further investigation (specificity of the combined staging procedures 91%). At 18 (6-37) months' follow-up, five of 26 (19%) patients with a positive sentinel node and four of 74 (5%) of patients with a negative sentinel node had recurrent or progressive disease. CONCLUSIONS: The combination of physical examination and lymph node US detects the great majority of patients with macroscopic lymph node metastasis (approximately 3% of patients at baseline). Only 10% of patients who have a histologically tumour-positive sentinel node are macroscopically detectable. Altogether, approximately 25% of patients have a positive sentinel node biopsy, among 90% microscopic. The value of whole body staging at baseline remains limited, since distant metastases can hardly ever be detected. The survival benefit of baseline staging and surveillance in patients with cutaneous MM remains to be established by comparative prospective trials.


Assuntos
Melanoma/patologia , Estadiamento de Neoplasias , Neoplasias Cutâneas/patologia , Abdome/diagnóstico por imagem , Adolescente , Adulto , Idoso , Reações Falso-Positivas , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Radiografia Torácica/métodos , Sensibilidade e Especificidade , Biópsia de Linfonodo Sentinela/métodos , Tomografia Computadorizada de Emissão/métodos , Ultrassonografia
8.
Eur J Cardiothorac Surg ; 23(5): 824-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12754040

RESUMO

OBJECTIVE: Prospective study to evaluate the feasibility of a preoperative bronchoscopic radioisotope application, followed by conventional sentinel lymph-node (SLN) identification and to investigate the occurrence and distribution of micrometastases in relation to SLN activity. METHODS: Twenty patients with a mean age of 63 years and proven clinical stage T1-3 N0-1 non-small-cell lung cancer (NSCLC) were included. A dosage of 80MBq radiolabeled technetium-99m nanocolloid was endoscopically administrated on intubated patients in the operation theatre. At thoracotomy, scintigraphic readings of both the primary tumor and hilar and mediastinal lymph-node stations were obtained with a hand-held gamma-counter. Patients underwent lung resection and mediastinal lymphadenectomy. Radiolabeled nodes were also examined separately on back-table. SLNs were defined as the hottest nodes or nodes with at least one-tenth of the radioactivity of the hottest nodes. SLNs pathologic assessment included standard examination using hematoxylin and eosin staining on step sections and immunohistochemistry (ICH) for cytokeratins. RESULTS: Identification of SLNs was possible in 19/20 (95%) patients after bronchoscopic radioisotope application. In 7/19 (37%) patients, a unique SLN was identified, whereas in 12/19 (63%) patients, nodes from two different stations could be classified as SLNs. Metastatic nodal disease was found in 9/19 (47%) patients. ICH revealed micrometastases in 2/12 (17%) patients, initially classified nodal negative. Pathologic negative SLNs were a predictor for absence of metastatic nodal disease after mediastinal lymphadenectomy. No complication related to the procedure was observed. CONCLUSION: Our preliminary results suggest that preoperative bronchoscopic radioisotope injection for SLN identification is a safe and simple method, improving accuracy of SLN detection in comparison to intraoperative technique. The absence of metastases in the SLNs seems to predict a negative nodal status accurately.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Compostos Radiofarmacêuticos , Biópsia de Linfonodo Sentinela/métodos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Idoso , Idoso de 80 Anos ou mais , Broncoscopia/métodos , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Metástase Linfática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos , Cintilografia , Sensibilidade e Especificidade
9.
Otolaryngol Head Neck Surg ; 125(3): 221-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11555757

RESUMO

OBJECTIVE: The aim of our study was to assess the feasibility of sentinel lymph node (SLN) radiolocalization in N0 neck in squamous cell head and neck carcinoma and its predictive value for occult metastasis. STUDY DESIGN: Nineteen patients of an open prospective trial. SETTING: After peritumoral injection of a 99m Tc labeled radiocolloid, the SLN was localized preoperatively by lymphoscintigraphy and intraoperatively through the intact skin by a hand-held gamma-probe. The histology of the SLN and the nodes of the elective neck dissection were compared. RESULTS: Localization of the SLN by lymphoscintigraphy was possible in 18 of 19, and with the hand-held gamma-probe in all 19 patients. Six SLN revealed occult metastatic disease. No skip metastasis were found in the 13 neck specimen with negative SLN. CONCLUSION: SLN evaluation in N0 neck in squamous cell carcinoma of the head and neck is accurately feasible and seems to adequately predict the presence of occult metastasis.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/patologia , Biópsia de Linfonodo Sentinela , Carcinoma de Células Escamosas/secundário , Estudos de Viabilidade , Humanos , Metástase Linfática/diagnóstico , Valor Preditivo dos Testes , Estudos Prospectivos , Cintilografia , Agregado de Albumina Marcado com Tecnécio Tc 99m , Neoplasias da Língua/patologia , Neoplasias Tonsilares/patologia
10.
Arch Dis Child ; 85(4): 341-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11567949

RESUMO

AIMS: To compare whole body positron emission tomography (PET) using fluorine-18-fluoro-2-deoxy-D-glucose (FDG) with computed tomography (CT) in detecting active infective foci in children with chronic granulomatous disease. METHODS: We performed 22 whole body FDG PET studies in seven children with X linked (n = 6) or autosomal recessive (n = 1) CGD. All had clinical signs of infection and/or were evaluated prior to bone marrow transplantation (BMT). Nineteen PET studies were also correlated with chest and/or abdominal CT. All PET scans were interpreted blinded to the CT findings. Diagnoses were confirmed histologically and bacteriologically. RESULTS: We detected 116 lesions in 22 FGD PETs and 126 lesions on 19 CTs. Only two of the latter could be classified reliably as active lesions by virtue of contrast enhancement suggesting abscess formation. PET excluded 59 lesions suspicious for active infection on CT and revealed 49 infective lesions not seen on CT. All seven active infective lesions were identified by PET, allowing targeted biopsy and identification of the infective agent followed by specific antimicrobial treatment, surgery, or subsequent BMT. CONCLUSIONS: Identification of infective organisms is more precise if active lesions are biopsied. CT does not discriminate between active and inactive lesions. Whole body FDG PET can be used to screen for active infective lesions in CGD patients.


Assuntos
Fluordesoxiglucose F18 , Doença Granulomatosa Crônica/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão , Irradiação Corporal Total , Adolescente , Antibacterianos/uso terapêutico , Biópsia , Transplante de Medula Óssea , Criança , Pré-Escolar , Fluordesoxiglucose F18/uso terapêutico , Doença Granulomatosa Crônica/terapia , Humanos , Masculino , Compostos Radiofarmacêuticos/uso terapêutico , Tomografia Computadorizada por Raios X
11.
Ter Arkh ; 73(10): 11-4, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11763507

RESUMO

AIM: To determine the impact of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) on patient management in radiotherapy. MATERIAL AND METHODS: One hundred sixty-nine consecutive patients with different malignant tumors were analyzed. Whole-body FDG-PET was performed for staging before radiotherapy. The strategy of radiotherapy before and after PET scanning was compared and the change in the treatment management determined. RESULTS: In 47(28%) of 169 patients PET results changed patient management in radiotherapy. In 19 patients (11%) radiotherapy was not performed after PET. In 16 patients (10%) PET results changed the intention of radiation treatment (curative/palliative). Correction of radiation dose was made in 16 patients (10%). Correction of the volume of the exposure area was made in 12 patients (7%). Tumor outside the field of view was missed in only 2 patients with a regional PET scan. CONCLUSION: In this retrospective analysis the information provided by FDG-PET contributes to a substantial change in radiotherapy strategy.


Assuntos
Fluordesoxiglucose F18 , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Compostos Radiofarmacêuticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias/patologia , Radioterapia/métodos , Estudos Retrospectivos , Tomografia Computadorizada de Emissão
12.
Eur J Pediatr ; 159(11): 835-42, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11079197

RESUMO

UNLABELLED: Cardiovascular risk factors in Prader-Willi syndrome (PWS, OMIM 176270) may be independently caused by overweight or hypothalamic growth hormone (GH) deficiency. The present observational study in 23 children with PWS, aged 0.3-14.6 years, focuses on the specific pattern, age-dependency and interrelation of cardiovascular risk factors, namely percentage fat mass and regional fat distribution, triglycerides (TG), lipoprotein cholesterols (LDL-C, HDL-C), lipoprotein (a) (Lp(a)), apolipoproteins A-I (Apo A-I) and B (Apo B), as well as on the longer-term effects of GH therapy (ca. 0.037 mg/kg per day for 3 years on average). We report that in children above 4 years, percentage body fat was increased in all and waist-to-hip-ratio (WHR) in 35%. Abnormal levels of LDL-C, Apo B, HDL-C and TG were found in 6, 7, 6 and 3 children, respectively. Lp(a) was above 300 mg/l in 5 patients and remained unchanged during GH therapy. However, percentage fat mass dropped to the upper normal range and WHR became normal in all patients receiving GH therapy, as did the ratio of LDL-C to HDL-C, subsequent to decreasing LDL-C and increasing HDL-C. Nevertheless, we could not find any significant correlation between parameters of total fat mass or fat distribution and serum lipid parameters, except for abdominal fat distribution (trunk-/leg-fat ratio) to TG before therapy. CONCLUSION: Several cardiovascular risk factors are already present in prepubertal children with Prader-Willi-syndrome and they are improved by growth hormone treatment, acting both on body composition and lipid metabolism.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Hormônio do Crescimento Humano/uso terapêutico , Síndrome de Prader-Willi/tratamento farmacológico , Tecido Adiposo/metabolismo , Antropometria , Composição Corporal , Criança , Pré-Escolar , Feminino , Humanos , Lipoproteínas/metabolismo , Masculino , Síndrome de Prader-Willi/metabolismo , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
13.
Horm Res ; 53(4): 200-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11044804

RESUMO

Obesity and hypothalamic GH deficiency contribute in different ways to the disturbances of body composition in Prader-Willi syndrome (PWS); while both increase the fat compartment, the reduction of lean tissue mass has been attributed mainly to GH deficiency. Therefore, body composition measured by dual-energy X-ray absorptiometry was prospectively studied in 12 overweight children with PWS and weight for height (WfH) SDS >0 before and during 3.5 years of treatment with hGH (0.037 mg/kg/day) on average. In the long term, there is a net reduction of body fat from 3.1 to 1.2 SD, with a minimum at the end of the second year of treatment. WfH SDS correctly reflects body fat mass and its changes. The initial deficit of lean mass (-1.6 SD) is counteracted by GH only during the first year of therapy (increase to -1.25 SD). But in the long term, GH therapy does not further compensate for this deficit, when lean mass is corrected for its growth-related increase. In conclusion, exogenous GH changes the phenotype of children with PWS: fat mass becomes normal, but, at least in the setting studied, GH is not sufficient to normalize lean tissue mass.


Assuntos
Composição Corporal , Hormônio do Crescimento Humano/uso terapêutico , Síndrome de Prader-Willi/tratamento farmacológico , Síndrome de Prader-Willi/fisiopatologia , Absorciometria de Fóton , Tecido Adiposo , Adolescente , Envelhecimento , Estatura , Criança , Pré-Escolar , Feminino , Hormônio do Crescimento Humano/administração & dosagem , Humanos , Masculino , Puberdade , Resultado do Tratamento
14.
Calcif Tissue Int ; 67(2): 116-21, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10920215

RESUMO

Bone loss and osteoporotic fractures are common in cardiac transplant recipients. To compare two prophylactic medical regimens after heart transplantation, 26 consecutive heart transplant recipients were randomized to receive either continuous oral calcitriol (0.5 microg/day) combined with nasal salmon calcitonin (200 U/day) for the first 3 months (group A) or intermittent intravenous pamidronate (0.5 mg/kg body weight) every third month (group B). Bone mineral density (BMD) and biochemical indices of bone turnover were measured at baseline and 3, 6, 12, and 18 months after transplantation. The mean pretransplant BMD, measured by dual energy X-ray absorptiometry (DXA) was significantly lower in the patients compared with age-matched healthy controls. During the first year of treatment, rates of bone loss at the lumbar spine and femoral neck were slightly but significantly slower in the patients treated with pamidronate, but there was no longer a significant difference between the two groups after 18 months of heart transplantation. Irrespective of the mode of osteoporosis prevention, osteocalcin levels increased whereas urinary deoxypyridinoline decreased after transplantation, and significant bone loss was observed in both treatment groups. We found no relationship between initial BMD, markers of bone turnover, cumulative glucocorticoid dose, or cyclosporine levels and the rate of bone loss after cardiac transplantation. In summary, we found that the rapid and severe bone loss following heart transplantation could be attenuated by two preventive measures, pamidronate or calcitriol with calcitonin.


Assuntos
Anti-Inflamatórios/uso terapêutico , Calcitonina/uso terapêutico , Calcitriol/uso terapêutico , Agonistas dos Canais de Cálcio/uso terapêutico , Difosfonatos/uso terapêutico , Transplante de Coração/efeitos adversos , Osteoporose/prevenção & controle , Absorciometria de Fóton , Administração Intranasal , Administração Oral , Adulto , Idoso , Aminoácidos/urina , Biomarcadores/sangue , Biomarcadores/urina , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Cálcio/urina , Feminino , Fêmur , Humanos , Estudos Longitudinais , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Osteoporose/sangue , Osteoporose/urina , Pamidronato
15.
Eur Radiol ; 10(5): 761-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10823629

RESUMO

The aim of this study was to compare prospectively the accuracy of whole-body positron emission tomography (PET), CT and MRI in diagnosing primary and recurrent ovarian cancer. Nineteen patients (age range 23-76 years) were recruited with suspicious ovarian lesions at presentation (n = 8) or follow-up for recurrence (n = 11). All patients were scheduled for laparotomy and histological confirmation. Whole-body PET with FDG, contrast-enhanced spiral CT of the abdomen, including the pelvis, and MRI of the entire abdomen were performed. Each imaging study was evaluated separately. Imaging findings were correlated with histopathological diagnosis. The sensitivity, specificity and accuracy for lesion characterization in patients with suspicious ovarian lesions (n = 7) were, respectively: 100, 67 and 86% for PET; 100, 67 and 86% for CT; and 100, 100 and 100% for MRI. For the diagnosis of recurrent disease (n = 10), PET had a sensitivity of 100%, specificity of 50% and accuracy of 90%. The PET technique was the only technique which correctly identified a single transverse colon metastasis. Results for CT were 40, 50 and 43%, and for MRI 86, 100 and 89%, respectively. No statistically significant difference was seen. Neither FDG PET nor CT nor MRI can replace surgery in the detection of microscopic peritoneal disease. No statistically significant difference was observed for the investigated imaging modalities with regard to lesion characterization or detection of recurrent disease; thus, the methods are permissible alternatives. The PET technique, however, has the drawback of less accurate spatial assignment of small lesions compared with CT and MRI.


Assuntos
Carcinoma/diagnóstico , Fluordesoxiglucose F18 , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia/diagnóstico , Neoplasias Ovarianas/diagnóstico , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X , Contagem Corporal Total , Adulto , Idoso , Carcinoma/secundário , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/secundário , Meios de Contraste , Feminino , Seguimentos , Humanos , Laparotomia , Pessoa de Meia-Idade , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/secundário , Estudos Prospectivos , Radiografia Abdominal , Sensibilidade e Especificidade
16.
Clin Pharmacol Ther ; 68(6): 598-604, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11180019

RESUMO

BACKGROUND: St John's Wort (hypericum perforatum) is an herbal medicine that is frequently used for therapy of mild depression. Recently, St John's Wort was reported to substantially decrease blood/plasma concentrations and efficacy of cyclosporine (INN, ciclosporin), indinavir, and digoxin. In this study we investigated the mechanisms of these St John's Wort-induced drug interactions. METHODS AND RESULTS: In a preclinical study, the administration of St John's Wort extract to rats during 14 days resulted in a 3.8-fold increase of intestinal P-glycoprotein/Mdrl expression and in a 2.5-fold increase in hepatic CYP3A2 expression (Western blot analyses). In a clinical study, the administration of St John's Wort extract to 8 healthy male volunteers during 14 days resulted in an 18% decrease of digoxin exposure after a single digoxin dose (0.5 mg), in 1.4- and 1.5-fold increased expressions of duodenal P-glycoprotein/MDR1 and CYP3A4, respectively, and in a 1.4-fold increase in the functional activity of hepatic CYP3A4 (14C-erythromycin breath test). CONCLUSIONS: These results indicate direct inducing effects of St John's Wort on intestinal P-glycoprotein/MDR1 (in rats and humans), hepatic CYP3A2 (in rats), and intestinal and hepatic CYP3A4 (in humans). Therefore the results provide a mechanistic explanation for the previously observed drug interactions in patients and support the importance of intestinal P-glycoprotein/MDR1 in addition to intestinal and hepatic CYP3A4 for overall drug absorption and disposition in humans.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Sistema Enzimático do Citocromo P-450/biossíntese , Hypericum/efeitos adversos , Intestino Delgado/efeitos dos fármacos , Fígado/efeitos dos fármacos , Oxigenases de Função Mista/biossíntese , Plantas Medicinais , Adulto , Animais , Disponibilidade Biológica , Cardiotônicos/farmacocinética , Citocromo P-450 CYP3A , Digoxina/farmacocinética , Interações Medicamentosas , Duodeno/efeitos dos fármacos , Duodeno/enzimologia , Duodeno/metabolismo , Indução Enzimática/efeitos dos fármacos , Humanos , Intestino Delgado/enzimologia , Intestino Delgado/metabolismo , Fígado/enzimologia , Masculino , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
17.
Eur Heart J ; 20(12): 910-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10329098

RESUMO

AIMS: Isolated ventricular non-compaction is a rare congenital cardiomyopathy with a high morbidity and mortality due to malignant arrhythmias and pump failure. Areas affected by non-compaction are characterized by increased trabecularization and deep inter-trabecular spaces. We hypothesized perfusion defects in these areas and performed positron emission tomography to evaluate the myocardial perfusion in non-compacted areas. METHODS AND RESULTS: Five children (age 10-14 years) with isolated ventricular non-compaction underwent positron emission tomography using N-13-ammonia as flow marker and intravenous dipyridamole for stress testing. Myocardial blood flow was quantified using the positron emission tomography time-activity curves in non-compacted areas and normal myocardium, which were diagnosed by echocardiography, magnetic resonance imaging, and angiography. Coronary angiography, performed in two children with extensive forms of left ventricular non-compaction, demonstrated normal coronary arteries. Myocardial blood flow measurements at rest and after dipyridamole application demonstrated 16-33% and 32-57% perfusion impairment, respectively, in non-compacted areas compared to normal myocardium. Areas of restricted myocardial perfusion corresponded well to the non-compacted areas, defined echographically and by magnetic resonance imaging. CONCLUSION: Positron emission tomography demonstrates restricted myocardial perfusion and decreased flow reserve in areas of ventricular non-compaction in children. The myocardial perfusion defects in non-compacted areas may be the cause of myocardial damage and possibly form the basis of arrhythmias and pump failure.


Assuntos
Circulação Coronária , Cardiopatias/congênito , Cardiopatias/fisiopatologia , Adolescente , Criança , Feminino , Coração/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Ventrículos do Coração , Humanos , Imageamento por Ressonância Magnética , Masculino , Miocárdio/patologia , Fluxo Sanguíneo Regional , Tomografia Computadorizada de Emissão , Ultrassonografia , Disfunção Ventricular/etiologia
18.
Melanoma Res ; 9(6): 569-73, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10661767

RESUMO

In oncology, a number of new potential therapeutic modalities, including gene targeting, are currently under investigation. To evaluate their response at a preclinical level, a non-invasive method providing information about cell proliferation would be highly valuable. The growth fraction can be assessed by the incorporation of thymidine into the DNA of S-phase cells. We report the use of the thymidine analogue bromodeoxyuridine (BrUdR) labelled with bromide-76 (76Br) in positron emission tomography (PET). PET scans using [76Br]BrUdR were performed in seven patients with metastatic melanoma. The in vitro cell proliferation in these metastases (n = 7) was compared with immunohistochemically evaluated cell proliferation using anti-bromo-deoxyuridine and MIB-1 antibodies after excision. Blood samples were taken to analyse the kinetics of the radiopharmaceutical. The accumulation of [76Br]BrUdR in PET correlated significantly with the immunohistochemically assessment of S-phase and cycling cells. In one patient a clinically unexpected metastases was found on [76Br]BrUdR-PET which became evident 4 weeks later. Analysis of blood samples showed a fast disappearance of [76Br]BrUdR; 30 min after injection free bromide was the main form of radioactivity, resulting in a high background activity. Assessment of cell proliferation using [76Br]BrUdR is hampered because of fast debromation and high background activity. The results are thus rather the effect of the increased circulation in more rapidly proliferating metastases than Incorporation of [76Br]BrUdR into proliferating cells.


Assuntos
Bromodesoxiuridina , Melanoma/diagnóstico por imagem , Tomografia Computadorizada de Emissão/métodos , Adulto , Idoso , Radioisótopos de Bromo , Divisão Celular , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanoma/patologia , Melanoma/secundário , Pessoa de Meia-Idade
19.
J Nucl Med ; 39(11): 1892-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9829578

RESUMO

UNLABELLED: This study describes a comparison of simulated planar positron coincidence scintigraphy (PCS) with PET in the whole-body staging of patients with malignant melanoma using 2-18F-fluoro-2-deoxy-D-glucose (FDG). METHODS: In 55 patients with either known metastatic or newly diagnosed malignant melanoma, whole-body PET scanning was performed on a conventional full-ring dedicated PET tomograph, and multiaxial sections were obtained. Furthermore, anteroposterior projection images simulating images of a dual-head Anger camera operating in coincidence mode were obtained from the PET raw data. Each study was evaluated separately and blindly. Imaging findings were confirmed by biopsy or by at least one imaging modality in addition to PET. RESULTS: A total of 108 lesions were evaluated, of which 76 proved to be melanoma metastases. Whole-body PET correctly demonstrated 68 metastases, 6 lesions were classified as questionable metastases and 2 were missed. Whole-body PCS correctly demonstrated 14 metastases, 22 lesions were classified as questionable metastases and 40 metastases were missed. The sensitivities of whole-body PET and whole-body PCS were 89% and 18%, respectively. In PCS lesions in regions of high background activity, such as in the abdomen, were missed more often than in PET (p < 0.05). The tumor-to-background contrast was generally lower in PCS than in PET. A further decrease in PCS detection was found in lesions of < 22 mm in diameter. CONCLUSION: The lack of sensitivity precludes the clinical use of whole-body PCS in staging malignant melanoma.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/secundário , Tomografia Computadorizada de Emissão , Adulto , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Neoplasias Cutâneas/patologia , Tomografia Computadorizada de Emissão/métodos
20.
Blood ; 92(8): 2719-24, 1998 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9763555

RESUMO

X-linked chronic granulomatous disease (X-CGD) is a primary immunodeficiency with complete absence or malfunction of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in the phagocytic cells. Life-threatening infections especially with aspergillus are common despite optimal antimicrobial therapy. Bone marrow transplantation (BMT) is contraindicated during invasive aspergillosis in any disease setting. We report an 8-year-old patient with CGD who underwent HLA-genoidentical BMT during invasive multifocal aspergillus nidulans infection, nonresponsive to treatment with amphotericin-B and gamma-interferon. During the first 10 days post-BMT, the patient received granulocyte colony-stimulating factor (G-CSF)-mobilized, 25 Gy irradiated granulocytes from healthy volunteers plus G-CSF beginning on day 3 to prolong the viability of the transfused granulocytes. This was confirmed in vitro by apoptosis assays and in vivo by finding nitroblue tetrazolium (NBT)-positive granulocytes in peripheral blood 12 and 36 hours after the transfusions. Clinical and biological signs of infection began to disappear on day 7 post-BMT. Positron emission tomography with F18-fluorodeoxyglucose (FDG-PET) and computed tomography (CT) scans at 3 months post-BMT showed complete disappearance of infectious foci. At 2 years post-BMT, the patient is well with full immune reconstitution and no sign of aspergillus infection. Our results show that HLA-identical BMT may be successful during invasive, noncontrollable aspergillus infection, provided that supportive therapy is optimal.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Aspergilose/terapia , Aspergillus nidulans , Transplante de Medula Óssea , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Doença Granulomatosa Crônica/terapia , Transfusão de Leucócitos , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Apoptose , Aspergilose/diagnóstico por imagem , Aspergilose/tratamento farmacológico , Aspergilose/prevenção & controle , Criança , Terapia Combinada , Portadores de Fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Granulócitos/fisiologia , Doença Granulomatosa Crônica/complicações , Humanos , Itraconazol/uso terapêutico , Contagem de Leucócitos , Lipossomos , Pneumopatias Fúngicas/tratamento farmacológico , Masculino , Tomografia Computadorizada de Emissão , Resultado do Tratamento
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