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1.
Clin Cancer Res ; 4(10): 2305-12, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9796959

RESUMO

Angiogenesis plays a fundamental role in tumor growth and metastasis. What is needed is a quantitative, noninvasive, and repeatable assay to estimate functional angiogenic activity of the entire tumor. The aims of the present study were to: (a) examine the relationship between functional magnetic resonance imaging (MRI)-based parameters with established histomorphological markers of tumor angiogenesis [histological microvessel density (HMVD) and vascular endothelial growth factor expression (VEGF)]; and (b) determine the ultimate value of both approaches to assess functional angiogenic active hotspots as markers of disease outcome in patients with cancer of the uterine cervix. Pharmacokinetic parameters (amplitude A, tissue exchange rate constant k21) were calculated from contrast-enhanced dynamic MRI series in 57 patients (mean age, 49 +/- 14 years) with biopsy proven uterine cervical cancer. Both pharmacokinetic parameters were correlated to histomorphologically determined areas of high HMVD and VEGF expression obtained from the operative specimens after radical surgery. In addition, the functional MRI and histomorphological data were used to assess disease outcome. A significant association was found between HMVD and the amplitude A (P < 0.001) and a less pronounced association with k21, (P < 0.05), respectively. No significant associations were found between the pharmacokinetic parameters (A, k21) and VEGF expression. When stratified into high and low median k21 groups, median k21 values >5.4 min(-1) were the only significant (P < 0.05) factors in predicting poor patient survival. None of the histomorphological markers of angiogenesis (HMVD or VEGF expression) showed any predictive power. We have found that: (a) focal hotspots of HMVD are the pathophysiological basis for differences in functional MRI; (b) areas of high microvessel density and microvessel permeability do not necessarily coincide, as demonstrated by the histomorphological and functional MRI findings; (c) the functional angiogenic activity of a tumor may not be sufficiently characterized by a histomorphological approach but rather by a functional MRI-based approach; and (d) functional MRI-based analysis may assess tumor angiogenic activity in terms of disease outcome more comprehensively than the histomorphological approach.


Assuntos
Neovascularização Patológica/diagnóstico , Neoplasias do Colo do Útero/irrigação sanguínea , Adulto , Idoso , Fatores de Crescimento Endotelial/análise , Feminino , Humanos , Linfocinas/análise , Imageamento por Ressonância Magnética , Microcirculação/patologia , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/patologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
2.
Cancer Res ; 58(16): 3598-602, 1998 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9721867

RESUMO

Dynamic studies of Gd-based contrast agents in magnetic resonance imaging (MRI) are increasingly being used for tumor characterization as well as for therapy response monitoring. Because detailed knowledge regarding the pathophysiological properties, which in turn are responsible for differences in contrast enhancement, remains fairly undetermined, it was the aim of this study to: (a) examine the association of standard and pharmacokinetic analysis of time-intensity curves in dynamic MRI with histomorphological markers of tumor angiogenesis [microvessel density (MVD) and vascular endothelial growth factor (VEGF)]; and (b) determine the ultimate value of a histomorphological and a dynamic MRI approach by the correlation of those data with disease outcome in patients with primary cancer of the uterine cervix. Pharmacokinetic parameters (amplitude, A; exchange rate constant, k21) and standard parameters [the maximum signal intensity increase over baseline (SI-I) and the steepest signal intensity-upslope per second (SI-U/s)] were calculated from a contrast-enhanced dynamic MRI series in 37 patients with biopsy-proven primary cervical cancer. On the surgical whole mount specimens, histomorphological markers of tumor angiogenesis (MVD and VEGF) were compared to MRI-derived parameters. For MRI and histomorphological data, Kaplan-Meier survival curves were calculated and compared using log-rank statistics. A significant association was found between MVD and A (P < 0.01) and SI-I (P < 0.05). No significant relationships were observed between VEGF expression and all dynamic MRI parameters. Kaplan-Meier curves based on k21 and SI-U/s showed that tumors with high k21 and SI-U/s values had a significantly (P < 0.05 and 0.001, respectively) worse disease outcome than did tumors with low k21 and SI-U/s values. None of the histomorphological gold standard markers for assessing tumor angiogenesis (MVD and VEGF) had any significant power to predict patient survival. It is concluded that in patients with uterine cervical cancer: (a) the pathophysiological basis for differences in dynamic MRI is MVD but not VEGF expression; (b) a functional, dynamic MRI approach (both standard and pharmacokinetic analysis) may be better suited to assess angiogenic activity in terms of patient survival than are the current histomorphological-based markers of tumor angiogenesis; and (c) compared with standard analysis, a simple pharmacokinetic analysis of time-intensity curves is not superior to assess MVD or patient survival.


Assuntos
Fatores de Crescimento Endotelial/metabolismo , Linfocinas/metabolismo , Imageamento por Ressonância Magnética/métodos , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Neoplasias do Colo do Útero/irrigação sanguínea , Meios de Contraste/farmacocinética , Feminino , Seguimentos , Humanos , Microcirculação , Pessoa de Meia-Idade , Neovascularização Patológica/diagnóstico , Variações Dependentes do Observador , Fatores de Tempo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/mortalidade , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
3.
Ultrasound Obstet Gynecol ; 6(5): 362-7, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8590210

RESUMO

In recent years, the incidence of carcinoma of the endometrium has shown an upward trend, such that it is currently the most frequently encountered malignant tumor of the female genital tract. An accurate preoperative diagnosis of the extent and spread of such carcinomas is of crucial importance for the selection of a therapeutic approach appropriate to the stage and infiltration of each particular tumor. In a prospective study of 80 patients with a carcinoma of the endometrium, performed at the Department of Obstetrics and Gynecology of the University of Mainz, we compared the preoperative findings of transvaginal sonography with the postoperative histological results with respect to the following parameters: endometrial thickness, demarcation of the boundary of the endometrium, myometrial infiltration depth and staging. In all of these patients, sonography revealed a distinct increase in the thickness of the endometrium. In all cases, the structure of the endometrium was found to be heterogenous, with an irregular and poorly delineated boundary. Assessments of the depth of tumor infiltration and the tumor staging obtained by transvaginal sonography were found to correlate with the histological findings in 85% and 87.5% of the cases, respectively. Thus, in cases of endometrial carcinoma, transvaginal sonography has an essential role to play in devising an individualized operative treatment program that takes into account the extent, spread and stage of the tumor.


Assuntos
Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/patologia , Miométrio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Miométrio/diagnóstico por imagem , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia , Vagina
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