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1.
Strahlenther Onkol ; 190(7): 676-85, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24577133

RESUMO

BACKGROUND: Survival upon diagnosis of brain metastases (BM) in patients with non-small cell lung cancer (NSCLC) is highly variable and established prognostic scores do not include tissue-based parameters. METHODS: Patients who underwent neurosurgical resection as first-line therapy for newly diagnosed NSCLC BM were included. Microvascular density (MVD), Ki67 tumor cell proliferation index and hypoxia-inducible factor 1 alpha (HIF-1 alpha) index were determined by immunohistochemistry. RESULTS: NSCLC BM specimens from 230 patients (151 male, 79 female; median age 56 years; 199 nonsquamous histology) and 53/230 (23.0%) matched primary tumor samples were available. Adjuvant whole-brain radiation therapy (WBRT) was given to 153/230 (66.5%) patients after neurosurgical resection. MVD and HIF-1 alpha indices were significantly higher in BM than in matched primary tumors. In patients treated with adjuvant WBRT, low BM HIF-1 alpha expression was associated with favorable overall survival (OS), while among patients not treated with adjuvant WBRT, BM HIF-1 alpha expression did not correlate with OS. Low diagnosis-specific graded prognostic assessment score (DS-GPA), low Ki67 index, high MVD, low HIF-1 alpha index and administration of adjuvant WBRT were independently associated with favorable OS. Incorporation of tissue-based parameters into the commonly used DS-GPA allowed refined discrimination of prognostic subgroups. CONCLUSION: Ki67 index, MVD and HIF-1 alpha index have promising prognostic value in BM and should be validated in further studies.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/secundário , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Antígeno Ki-67/metabolismo , Microvasos/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Análise de Sobrevida
2.
Clin Neuropathol ; 29(1): 41-54, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20040333

RESUMO

Brain tumors comprise a large spectrum of rare malignancies in children and adults that are often associated with severe neurological symptoms and fatal outcome. Neuropathological tumor typing provides both prognostic and predictive tissue information which is the basis for optimal postoperative patient management and therapy. Molecular biomarkers may extend and refine prognostic and predictive information in a brain tumor case, providing more individualized and optimized treatment options. In the recent past a few neuropathological brain tumor biomarkers have translated smoothly into clinical use whereas many candidates show protracted translation. We investigated the causes of protracted translation of candidate brain tumor biomarkers. Considering the research environment from personal, social and systemic perspectives we identified eight determinants of translational success: methodology, funding, statistics, organization, phases of research, cooperation, self-reflection, and scientific progeny. Smoothly translating biomarkers are associated with low degrees of translational complexity whereas biomarkers with protracted translation are associated with high degrees. Key issues for translational efficiency of neuropathological brain tumor biomarker research seem to be related to (i) the strict orientation to the mission of medical research, that is the improval of medical practice as primordial purpose of research, (ii) definition of research priorities according to clinical needs, and (iii) absorption of translational complexities by means of operatively beneficial standards. To this end, concrete actions should comprise adequate scientific education of young investigators, and shaping of integrative diagnostics and therapy research both on the local level and the level of influential international brain tumor research platforms.


Assuntos
Biomarcadores/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Pesquisa Translacional Biomédica/métodos , Neoplasias Encefálicas/patologia , Educação/métodos , Humanos , Cooperação Internacional , Prognóstico
3.
Eur J Neurol ; 16(7): 874-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19473360

RESUMO

BACKGROUND: Peritumoral brain edema in glioblastoma patients is a frequently encountered phenomenon that strongly contributes to neurological signs and symptoms. The role of peritumoral edema as a prognostic factor is controversial. MATERIALS AND METHODS: This multi-centre clinical retrospective study included 110 patients with histologically proven glioblastoma. The prognostic impact on overall survival of pre-treatment peritumoral edema detected on MRI-scans was evaluated. All patients had preoperative MRI, surgery, histology, and received standard treatment regimens. Edema on MRI-scans was classified as minor (<1 cm), and major (>1 cm). RESULTS: Our results confirm that peritumoral edema on preoperative MRI is an independent prognostic factor in addition to postoperative Karnofsky performance score (KPS), age, and type of tumor resection. Patients with major edema had significant shorter overall survival compared to patients with minor edema. CONCLUSION: This easily applicable early radiological characterization may contribute to a more subgroup oriented treatment in glioblastoma patients for future trials, as well as in clinical routine.


Assuntos
Edema Encefálico/patologia , Neoplasias Encefálicas/diagnóstico , Glioblastoma/complicações , Glioblastoma/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Edema Encefálico/etiologia , Edema Encefálico/mortalidade , Mapeamento Encefálico , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/mortalidade , Intervalos de Confiança , Feminino , Glioblastoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Razão de Chances
4.
Histopathology ; 53(1): 39-47, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18613924

RESUMO

AIMS: The Ki67 tumour cell proliferation index is an independent prognostic factor in ependymoma patients. Essential prerequisites for validation of the Ki67 index as a histopathological biomarker are the reproducibility of this factor and its prognostic influence by different observers (proof of objective clinical and analytical performance). To this end, the aim was to analyse systematically inter- and intraobserver agreement and reproducibility of the prognostic impact of the Ki67 index in intracranial ependymoma. METHODS AND RESULTS: The study cohort contained 78 cases of intracranial ependymoma. In all cases, the Ki67 index was assessed by four experienced observers (EOs) and by four inexperienced observers (IOs) using the manual hot-spot method. There was considerable agreement on Ki67 index assessment. There was higher observer agreement among EOs compared with IOs. For each observer, survival analysis showed significant association of low Ki67 index with favourable patient outcome. CONCLUSIONS: Our data show that the Ki67 index in intracranial ependymoma is a reproducible and robust prognostic factor and can be considered a promising histopathological candidate biomarker. Attainment of biomarker status requires further translational studies in the context of prospective therapeutic trials.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Encefálicas/química , Neoplasias Encefálicas/patologia , Ependimoma/química , Ependimoma/patologia , Antígeno Ki-67/análise , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Contagem de Células , Proliferação de Células , Criança , Pré-Escolar , Ependimoma/mortalidade , Humanos , Imuno-Histoquímica , Lactente , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos
5.
Eur J Clin Invest ; 37(8): 665-72, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17635578

RESUMO

BACKGROUND: Pituitary adenylate cyclase activating polypeptide 1-38 (PACAP38) displays biological activities (e.g. bronchodilatory, pulmonary vasodilatory and anti-inflammatory properties) that are relevant in several pulmonary diseases. The aim of this study was to assess the safety and tolerability and the pulmonary and systemic effects of inhaled PACAP38 in humans. MATERIALS AND METHODS: Twelve healthy male subjects (mean age 28) were studied in a randomized, double-blind, placebo-controlled dose escalation trial with inhalation of PACAP38 to a cumulative dose of 480 microg. Lung function was measured by body plethysmography. Systemic absorption was evaluated by plasma levels, skin blood flux (estimated by laser Doppler imager fluxmetry) and systemic haemodynamics. RESULTS: Inhalation of PACAP38 did not cause relevant adverse reactions or an increase of PACAP38 plasma levels. No statistically significant changes in lung function tests and no systemic effects (blood pressure, pulse rate or skin blood flux) occurred. CONCLUSION: Inhaled PACAP38 was well tolerated without systemic side-effects in healthy male subjects.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/efeitos adversos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Respiração/efeitos dos fármacos , Vasodilatadores/efeitos adversos , Administração por Inalação , Adulto , Método Duplo-Cego , Humanos , Masculino , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/administração & dosagem , Testes de Função Respiratória/métodos , Pele/irrigação sanguínea , Pele/efeitos dos fármacos , Vasodilatadores/administração & dosagem
6.
Kidney Int ; 70(11): 2014-20, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17051143

RESUMO

It is currently not known which level of pentagastrin-stimulated calcitonin serum concentration indicates medullary thyroid carcinoma in patients with chronic kidney disease (CKD). We examined CKD stage 3-5 patients who had total thyroidectomy because of a pentagastrin-stimulated calcitonin concentration greater than 100 pg/ml, and tested the diagnostic performance of basal and pentagastrin-stimulated calcitonin levels for differentiating medullary thyroid carcinoma and C-cell hyperplasia in this patient population. A total of 180 CKD patients presented with an elevated calcitonin level and had a pentagastrin stimulation test. Forty patients showed a maximum pentagastrin-stimulated calcitonin concentration greater than 100 pg/ml, and 22 patients had a total thyroidectomy. Seven of these 22 patients presented with a medullary thyroid carcinoma, all other patients showed C-cell hyperplasia. Patients with medullary thyroid carcinoma showed higher unstimulated (212 pg/ml (36-577) vs 42 pg/ml (17-150); P < 0.001) and higher maximum pentagastrin-stimulated calcitonin concentrations (862 pg/ml (431-2423) vs 141 pg/ml (102-471); P < 0.001) as compared to patients with C-cell hyperplasia. The sensitivity (100%) and specificity (93%) estimates suggested that a maximum pentagastrin-stimulated calcitonin concentration greater than 400 pg/ml indicates the presence of medullary thyroid carcinoma in patients with CKD. Receiver-operating characteristic (ROC) analysis revealed an area under the ROC plot of 0.99 for maximum pentagastrin-stimulated calcitonin concentrations. A maximum pentagastrin-stimulated calcitonin concentration greater than 400 pg/ml appears to be a clinically meaningful threshold for thyroidectomy.


Assuntos
Calcitonina/sangue , Carcinoma Medular/diagnóstico , Insuficiência Renal Crônica/metabolismo , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Humanos , Hiperplasia/diagnóstico , Masculino , Pessoa de Meia-Idade , Pentagastrina , Curva ROC , Insuficiência Renal Crônica/complicações , Glândula Tireoide/cirurgia , Tireoidectomia
7.
Eur J Cancer ; 42(17): 2996-3003, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16996732

RESUMO

Standard postoperative treatment of medulloblastoma consists of craniospinal irradiation and chemotherapy. Currently, only clinical factors are used for therapy stratification. To optimise treatment and patient outcome, biological prognostic markers are needed. In the present study we tested the prognostic influence of four histopathological parameters considered in recent publications as prognostic factors in medulloblastoma. We analysed a series of 82 Austrian medulloblastoma patients who were treated according to the consecutive HIT protocols for medulloblastoma conducted by the German Society of Paediatric Haematology and Oncology. Histological subtype and immunohistochemical expression of erbB-2, TRKC, and survivin were determined on paraffin embedded tumour tissue and correlated with patient outcome. Statistical analysis showed a significant correlation of high expression levels of survivin with decreased survival. None of the other investigated histopathological factors correlated significantly with patient outcome. Our data indicate that high survivin expression is related to unfavourable clinical outcome in medulloblastoma patients.


Assuntos
Neoplasias Cerebelares/patologia , Meduloblastoma/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/metabolismo , Adolescente , Adulto , Neoplasias Cerebelares/mortalidade , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Proteínas Inibidoras de Apoptose , Masculino , Meduloblastoma/mortalidade , Prognóstico , Receptor ErbB-2/metabolismo , Receptor trkC/metabolismo , Análise de Sobrevida , Survivina
8.
Histopathology ; 48(4): 438-44, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16487366

RESUMO

AIMS: NeuN is considered to be a marker of neuronal differentiation in brain tumours. Our aim was to perform, for the first time, a systematic and comparative analysis of NeuN expression in all major brain tumour subtypes to provide guidance for the rational use of NeuN immunohistochemistry in diagnostic histopathology. METHODS AND RESULTS: Anti-NeuN immunohistochemistry was performed on paraffin-embedded biopsy specimens of 106 diffuse astrocytomas, 100 pilocytic astrocytomas, 107 ependymomas, 59 1p-aberrant oligodendroglial neoplasms, 115 glioblastomas, 115 medulloblastomas, 14 gangliogliomas/gangliocytomas and 10 central neurocytomas. We found no NeuN expression in pilocytic astrocytoma, whereas all other investigated tumour subtypes showed focal or widespread expression in varying proportions of cases. Comparing NeuN expression in clear cell tumours, widespread NeuN expression had a positive predictive value of 76.9% (95% confidence interval 46.2, 95.0) for central neurocytoma. Lack of NeuN expression had a positive predictive value of 87.3% (76.5, 94.4) for oligodendroglioma. CONCLUSIONS: Immunohistochemistry can detect NeuN expression in all major brain tumour subtypes except pilocytic astrocytoma. In the individual case, assessment of NeuN expression may be helpful in the differential diagnosis of clear cell primary brain tumours but does not seem to be useful for the differential diagnosis of other brain tumour subtypes.


Assuntos
Antígenos Nucleares/análise , Neoplasias Encefálicas/patologia , Proteínas do Tecido Nervoso/análise , Astrocitoma/metabolismo , Astrocitoma/patologia , Neoplasias Encefálicas/metabolismo , Diagnóstico Diferencial , Ependimoma/metabolismo , Ependimoma/patologia , Ganglioglioma/metabolismo , Ganglioglioma/patologia , Ganglioneuroma/metabolismo , Ganglioneuroma/patologia , Humanos , Imuno-Histoquímica , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Neurocitoma/metabolismo , Neurocitoma/patologia , Oligodendroglioma/metabolismo , Oligodendroglioma/patologia , Valor Preditivo dos Testes
9.
Clin Orthop Relat Res ; (392): 394-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11716413

RESUMO

Because of the enormous progress in surgery in the treatment of patients with tumors, the current study analyzed the influence of wide surgical resection margins on the outcome of patients with Ewing's sarcoma. Between 1980 and 1994, 86 patients were treated with systemic therapy and surgery (biopsy in six patients, tumor resection in 80 patients). Forty-four patients also had radiation therapy. The 5-year overall survival was 56.8% (5-year disease-free survival, 59.4%). The 5-year overall survival after radical or wide resection was 60.2% (5-year disease-free survival, 58.2%), in comparison with 40.1% (46.7%) after marginal or intralesional resection. Two patients with inadequate resection margins had local recurrences. In addition to the influence of neoadjuvant chemotherapy for higher survival rates (5-year overall survival with a good response was 80.2% versus 41.7% with a poor response), adequate surgical margins significantly affect the outcome for patients with Ewing's sarcoma.


Assuntos
Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/cirurgia , Sarcoma de Ewing/mortalidade , Sarcoma de Ewing/cirurgia , Adolescente , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/radioterapia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/patologia , Sarcoma de Ewing/radioterapia , Análise de Sobrevida
10.
Eur J Surg Oncol ; 27(6): 569-73, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11520091

RESUMO

AIMS: The treatment of patients suffering from Ewing's sarcoma has changed over the last three decades. We report the analyses, significant prognostic factors, interdisciplinary approach and development of therapy in one institution in Austria. METHODS: One hundred and forty-two patients treated for Ewing's sarcoma between 1949 and 1994 were reviewed. Median follow-up was 8.5 years. Fifty-six patients were treated between 1949 and 1980 (group 1), and 86 patients between 1981 and 1994 (group 2). Patients in group 1 were treated with polychemotherapy. Patients in group 2 were treated with a neoadjuvant CESS (Cooperative Ewing's Sarcoma Study) regimen. In group 1, 24 patients underwent biopsy only, 32 patients had a definitive operation, 48 patients received either radiation therapy only or additional radiation therapy compared with in group 2: 6, 80 and 44 cases, respectively. RESULTS: Five-year overall survival (OS) increased from 27% to 57%. Significant prognostic factors for OS were pre-operative metastases (P=0.0001), tumour location (P=0.0048), type of chemotherapy (P=0.002) and response to chemotherapy (P=0.0004). Chemotherapy (P=0.037), tumour location (P=0.0017) and metastases at diagnosis (P=0.0025) were significant. CONCLUSION: The most effective treatment of Ewing's sarcoma is chemotherapy.


Assuntos
Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/terapia , Sarcoma de Ewing/mortalidade , Sarcoma de Ewing/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Áustria , Biópsia por Agulha , Neoplasias Ósseas/diagnóstico , Criança , Pré-Escolar , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Procedimentos Ortopédicos/métodos , Probabilidade , Radioterapia Adjuvante/métodos , Estudos Retrospectivos , Sarcoma de Ewing/diagnóstico , Sensibilidade e Especificidade , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
11.
Clin Orthop Relat Res ; (388): 167-77, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11451116

RESUMO

Between 1982 and 1989, 100 primary lower limb reconstructions were done using the Kotz Modular Femur Tibia Reconstruction System after resection of a malignant tumor. In 32 patients a proximal femur prosthesis was implanted, in 40 patients a distal femur prosthesis was implanted, in 19 patients a proximal tibia component was implanted, in four patients a total femur prosthesis was implanted, and in five patients a total knee prosthesis was implanted. The Kaplan-Meier estimate of the overall survival rate of the prostheses was 85% after 3 years, 79% after 5 years, and 71% after 10 years. The most common reason for implant failure was aseptic loosening in 27% of patients (11 patients; range, 10-121 months) after the initial operation. The other reasons for revision surgery were implant fracture (n 5 4) and infection (n 5 4). Early repair of prostheses-related minor complications, such as worn polyethylene bushings, resulted in a statistically significant reduction of implant failure. After a median followup of 127.5 months after the initial surgery, 51 patients had died and eight patients were lost to followup. Forty-one patients were evaluated clinically and radiologically using the Musculoskeletal Tumor Society score and the radiologic implant evaluation system of the International Symposium on Limb Salvage; these 41 patients had a mean of 80% (range, 40%-100%) of the normal functional capability.


Assuntos
Neoplasias Ósseas/cirurgia , Neoplasias Femorais/cirurgia , Osteossarcoma/cirurgia , Próteses e Implantes , Tíbia , Adulto , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/mortalidade , Quimioterapia Adjuvante , Neoplasias Femorais/tratamento farmacológico , Neoplasias Femorais/mortalidade , Seguimentos , Humanos , Pessoa de Meia-Idade , Osteossarcoma/tratamento farmacológico , Osteossarcoma/mortalidade , Desenho de Prótese , Procedimentos de Cirurgia Plástica
12.
J Cataract Refract Surg ; 27(6): 861-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11408132

RESUMO

PURPOSE: To evaluate the feasibility of using a new optical biometry technique, dual-beam partial coherence interferometry (PCI), to improve intraocular lens (IOL) power prediction in cataract surgery. SETTING: Department of Ophthalmology, Vienna General Hospital, and Institute of Medical Physics, University of Vienna, Vienna, Austria. METHODS: Preoperative axial length (AL) data obtained with PCI biometry and applanation ultrasound (US) biometry in 77 eyes of 51 patients was applied to 4 commonly used IOL power formulas. The refractive outcome and the mean absolute error (MAE) were calculated for each formula using both biometry methods. A linear multiple-regression model based on preoperative PCI biometry data was derived to predict the postoperative anterior chamber depth (ACD). The predictive power of this regression model was assessed by adding the predicted ACD to the SRK/T formula. Predicted residuals were calculated to evaluate the feasibility and stability of this modified IOL power formula. RESULTS: Using PCI instead of US biometry significantly improved the refractive outcome with all 4 IOL power formulas. The Holladay I and SRK/T formulas yielded an MAE of 0.44 diopter (D) using PCI AL data and 0.56 D and 0.57 D, respectively, using US biometry data. The SRK/T formula combined with the PCI regression model for postoperative ACD prediction performed slightly better (MAE 0.42 D) than the conventional SRK/T formula alone. Predicted residuals revealed an MAE of 0.46 D, proving the predictive performance of the new formula. CONCLUSIONS: Partial coherence interferometry biometry applied to several widely used IOL power formulas yielded significantly better IOL power prediction and therefore refractive outcome in cataract surgery than US biometry. Further improvement can be achieved by applying PCI to a modified SRK/T formula that predicts the postoperative ACD using PCI biometry data.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Lentes Intraoculares , Óptica e Fotônica , Biometria/métodos , Extração de Catarata , Estudos de Viabilidade , Humanos , Interferometria , Implante de Lente Intraocular , Som
13.
Eur J Anaesthesiol ; 18(4): 238-44, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11350461

RESUMO

BACKGROUND AND OBJECTIVE: We studied the influence of systemic (aortic) blood flow velocity on changes of cerebral blood flow velocity under isoflurane or sevoflurane anaesthesia. METHODS: Forty patients (age: isoflurane 24-62 years; sevoflurane 24-61 years; ASA I-III) requiring general anaesthesia undergoing routine spinal surgery were randomly assigned to either group. Cerebral blood flow velocity was measured in the middle cerebral artery by transcranial Doppler sonography (depth: 50-60 mm). Systemic blood flow velocity was determined by transthoracic Doppler sonography at the aortic valve. Heart rate, arterial pressure, arterial oxygen saturation and body temperature were monitored. After standardized anaesthesia induction (propofol, remifentanil, vecuronium) sevoflurane or isoflurane were used as single agent anaesthetics. Cerebral blood flow velocity and systemic blood flow velocity were measured in the awake patient (baseline) and repeated 5 min after reaching a steady state of inspiratory and end-expiratory concentrations of 0.75, 1.00, and 1.25 mean alveolar concentrations of either anaesthetic. To calculate the influence of systemic blood flow velocity on cerebral blood flow velocity, we defined the cerebral-systemic blood flow velocity index (CSvI). CSvI of 100% indicates a 1:1 relationship of changes of cerebral blood flow velocity and systemic blood flow velocity. RESULTS: Isoflurane and sevoflurane reduced both cerebral blood flow velocity and systemic blood flow velocity. The CSvI decreased significantly at all three concentrations vs. 100% (isoflurane/sevoflurane: 0.75 MAC: 85 +/- 25%/81 +/- 23%, 1.0 MAC: 79 +/- 19%/74 +/- 16%, 1.25 MAC: 71 +/- 16%/79 +/- 21%; [mean +/- SD] P = 0.0001). CONCLUSIONS: The reduction of the CSvI vs. 100% indicates a direct reduction of cerebral blood flow velocity caused by isoflurane/sevoflurane, independently of systemic blood flow velocity.


Assuntos
Anestesia por Inalação , Anestésicos Inalatórios , Circulação Cerebrovascular/efeitos dos fármacos , Isoflurano , Éteres Metílicos , Artéria Cerebral Média/efeitos dos fármacos , Adulto , Aorta/fisiologia , Método Duplo-Cego , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sevoflurano
14.
J Clin Epidemiol ; 54(1): 99-103, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11165473

RESUMO

The aim of many epidemiological studies is the regression of a dichotomous outcome (e.g., death or affection by a certain disease) on prognostic covariables. Thereby the Poisson regression model is often used alternatively to the logistic regression model. Modelling the number of events and individual outcomes, respectively, both models lead to nearly the same results concerning the parameter estimates and their significances. However, when calculating the proportion of explained variation, quantified by an R2 measure, a large difference between both models usually occurs. We illustrate this difference by an example and explain it with theoretical arguments. We conclude, the R2 measure of the Poisson regression quantifies the predictability of event rates, but it is not adequate to quantify the predictability of the outcome of individual observations.


Assuntos
Interpretação Estatística de Dados , Métodos Epidemiológicos , Modelos Lineares , Modelos Logísticos , Distribuição de Poisson , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Doença das Coronárias/etiologia , Doença das Coronárias/mortalidade , Seguimentos , Humanos , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Fumar/efeitos adversos , Reino Unido/epidemiologia
15.
Clin Cancer Res ; 6(9): 3417-23, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10999723

RESUMO

Drug resistance of non-Hodgkin's lymphomas may involve mechanisms of the multidrug resistance phenotype including the lung resistance protein (LRP) and the multidrug resistance protein (MRP1). To determine the clinical relevance of these multidrug resistance factors in previously untreated diffuse large B-cell lymphomas (n = 48), we studied LRP and MRP1 expression in lymphoma cells and their impact on clinical outcome. LRP and MRP1 expression were immunohistochemically assessed by means of the monoclonal antibodies LRP-56 and MRPr1, respectively. LRP was positive in 23% and MRP1 in 44% of the samples. LRP expression was associated with higher tumor stage (P = 0.03), elevated serum lactate dehydrogenase levels (P = 0.01), and the International Prognostic Index (P = 0.0001). LRP-positive patients had a lower complete response rate to polychemotherapy than LRP-negative patients (18 versus 65%; P = 0.006). Patients with LRP expression had a shorter overall survival than those without LRP expression (median of 0.9 years versus median not reached; P = 0.001). MRP1 expression was independent of clinical and laboratory parameters and had no impact on the outcome of chemotherapy or survival of the patients. These data suggest that LRP expression but not MRP1 expression is an important mechanism of drug resistance associated with worse clinical outcome in previously untreated diffuse large B-cell lymphomas. Thus, the reversal of LRP-mediated drug resistance may improve clinical outcome in diffuse large B-cell lymphoma in the future.


Assuntos
Transportadores de Cassetes de Ligação de ATP/biossíntese , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas de Neoplasias/biossíntese , Partículas de Ribonucleoproteínas em Forma de Abóbada/biossíntese , Análise de Variância , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bleomicina/administração & dosagem , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Doxorrubicina/administração & dosagem , Resistência a Múltiplos Medicamentos , Etoposídeo/administração & dosagem , Feminino , Humanos , Imuno-Histoquímica , Lomustina/administração & dosagem , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Prednimustina/administração & dosagem , Prednisona/administração & dosagem , Análise de Regressão , Análise de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem
16.
Comput Methods Programs Biomed ; 63(1): 71-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10927156

RESUMO

Kent and O'Quigley (1988) apply the concept of information gain to define a measure of dependence (R-squared measure) between explanatory variables and a censored response variable within the framework of the Cox model. Two SAS macros to calculate this measure are presented. The first one is based on a Newton-Raphson search and makes use of the SAS IML procedure. The second one is a simple grid search using SAS DATA steps and Base-SAS procedures.


Assuntos
Interpretação Estatística de Dados , Análise Numérica Assistida por Computador , Modelos de Riscos Proporcionais , Software , Análise de Sobrevida , Humanos , Modelos Lineares , Neoplasias Pulmonares/mortalidade , Masculino , Reprodutibilidade dos Testes
17.
Radiother Oncol ; 55(2): 135-44, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10799725

RESUMO

BACKGROUND AND PURPOSE: To evaluate prospectively local tumor control and morbidity after 1-3 fractions of stereotactic external beam irradiation (SEBI) in patients with uveal melanoma, unsuitable for ruthenium-106 brachytherapy or local resection. MATERIAL AND METHODS: This phase I/II study includes 62 selected patients with uveal melanoma. The mean initial tumor height was 7.8+/-2.8 mm. With the Leskell gamma knife SEBI, 41 patients (66%) were irradiated with two equal fractions of 35, 30 or 25 Gy/fraction, 14 patients (22%) were treated with three fractions of 15 Gy each, and seven patients (11%) with small tumor volumes below 400 mm(3) were treated with one fraction of 45 Gy. The mean total dose was 54+/-8 Gy. The minimal follow-up period was 12 months, and the median follow-up was 28.3 months. Data on radiation-induced side-effects were analyzed with the Cox proportional hazards model for possible risk factors. RESULTS: Local tumor control was achieved in 98% and tumor height reduction in 97%. The mean relative tumor volume reductions were 44, 60 and 72% after 12, 24 and 36 months, respectively. Seven patients developed metastases (11%). Secondary enucleation was performed in eight eyes (13%). Morbidity was significant in tumors exceeding 8 mm in initial height; it was comparable and acceptable in those smaller. In the stepwise multiple Cox model, tumor localization, height and volume, planning target volume (PTV), total dose and patient age were identified as the strongest risk factors for radiation-induced lens opacities, secondary glaucoma, uveitis, eyelash loss and exudative retinal detachment. In this model, the high-dose volume irradiated with more than 10 Gy/fraction was the strongest risk factor for radiation-induced uveitis. CONCLUSIONS: Stereotactic external photon beam irradiation and a total dose of 45-70 Gy delivered in one to three fractions are highly effective at achieving local tumor control in uveal melanoma. Further clinical studies using smaller fraction doses, and consequent smaller high-dose volumes, are justified to optimize dose and fractionation. Fractionated stereotactic irradiation has a challenging potential as an eye-preserving treatment in uveal melanoma.


Assuntos
Melanoma/cirurgia , Radiocirurgia , Neoplasias Uveais/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiocirurgia/efeitos adversos , Fatores de Risco
18.
Leukemia ; 14(1): 68-76, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10637479

RESUMO

To compare the clinical relevance of drug resistance factors in de novo acute myeloid leukemia (AML), we determined their relationship to both response to induction chemotherapy and survival of the patients in univariate as well as multivariate analyses. The drug resistance factors immunocytochemically studied in 111 patients at the time of diagnosis included the lung resistance protein (LRP), P-glycoprotein (P-gp), multidrug resistance protein (MRP1) and bcl-2. In the univariate analyses, age (P = 0.005), karyotype (P = 0.03), LRP (P = 0.003), P-gp (P = 0.02) and bcl-2 (P = 0.03) predicted for response to induction chemotherapy, whereas MRP1 had no predictive value. Age (P = 0.05), karyotype (P = 0.05) and LRP (P = 0.03) retained their predictive value in the multivariate logistic regression analyses. With regard to overall survival, age (P = 0. 008), karyotype (P = 0.006), LRP (P = 0.001) and P-gp (P = 0.01) were of prognostic value in the univariate Cox regression analyses but only age (P = 0.01), karyotype (P = 0.02) and LRP (P = 0.01) retained their prognostic significance in the multivariate analyses. A risk score based on the number of independent prognostic factors allowed division of patients into four groups with different outcome. In these groups, the complete remission rates were 93%, 75%, 47% and 33%, respectively, and median overall survival was 2.4, 1.2, 0.6 and 0.2 years, respectively. Thus, several drug resistance factors did predict outcome in the univariate analyses but LRP was the only drug resistance factor with independent predictive and prognostic significance. The proposed risk score might be useful for risk-adapted treatment in the future. Leukemia (2000) 14, 68-76.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Imuno-Histoquímica , Cariotipagem , Leucemia Mieloide/genética , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
19.
Br J Cancer ; 81(4): 662-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10574252

RESUMO

The prognostic influence of CA 125 regression between the time point before surgery and after two completed courses of chemotherapy was studied in 210 patients with advanced ovarian cancer, and was compared to other well established prognostic factors. CA 125 blood samples were collected preoperatively (CA 125 pre) and 3 months after surgery (CA 125 3 mo) (at the beginning of the 3rd cycle of chemotherapy). The parameter CA 125 regression defined as log10 (CA 125 3 mo/CA 125 pre) was used for statistical analysis. In a survival analysis using a Cox proportional hazards model, CA 125 regression (P = 0.0001), residual tumour (P = 0.0001), age (P = 0.0095) and grading (P = 0.044) were independent variables, whereas stage of disease, histology, ascites and type of surgery failed to retain significance. Using log10 (CA 125 3 mo/CA 125 pre) as simple covariate in a Cox model showed a hazard ratio of 1.70 (95% confidence interval 1.32-2.19, P = 0.0001). However, a detailed analysis of the interaction of time with the prognostic factor CA 125 regression on survival revealed a strong time-dependent effect with a hazard ratio of more than 6 immediately after two courses of chemotherapy, whereas within approximately 1 year the hazard ratio for the surviving patients dropped quickly to the neutral level of 1. In summary, CA 125 regression is an independent prognostic factor for survival of women with advanced ovarian cancer and allows an identification of a high-risk population among patients with advanced ovarian cancer. However, the discriminating power of serial CA 125 for long-term survival seems to be temporary and prediction of individual patients outcome is far less precise.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno Ca-125/sangue , Neoplasias Ovarianas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/tratamento farmacológico , Prognóstico , Taxa de Sobrevida
20.
Photodermatol Photoimmunol Photomed ; 15(1): 18-21, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9990664

RESUMO

Chronic skin ulcers still represent a therapeutic challenge in dermatology. Among the various non-invasive treatment modalities used for the improvement of impaired wound healing, low-intensity laser irradiations are gaining an increasing body of interest. We used low-intensity laser irradiations delivered by a 30 mW helium-neon laser at an energy density of 30 J/cm2 three times weekly for the induction of wound healing in ulcers of diverse causes. Twenty patients with the same number of ulcers, which had previously been treated by conventional wound care for a median period of 34 weeks (range: 3-120 weeks) without any significant evidence of healing, were included in the study. Concerning the underlying disorders, patients were divided into four groups: diabetes, arterial insufficiency, radio damage and autoimmune vasculitis. In all ulcers, complete epithelization could be induced by laser therapy. No amputation or any other surgical intervention was necessary and no adverse effects of any kind were noted during low-intensity laser treatment. Regarding the different diagnoses, a statistically significant difference was noted (P = 0.008): ulcers due to radio damage healed significantly faster than those caused by diabetes (6 weeks [range: 3-10 weeks] vs. 16 weeks [range: 9-45 weeks], P = 0.005). Wound healing in autoimmune vasculitis (24 weeks [range: 20-35 weeks]) required longer than in radiodermitis, although the difference was not significant. In addition to the diagnosis, wound size was found to be an important factor influencing the duration of wound closure (P = 0.028), whereas duration of previous conventional treatment (P = 0.24) and depth (P = 0.14) showed no effect. Our results indicate that low-intensity laser irradiation could be a valuable non-invasive tool for the induction of wound healing in recalcitrant ulcers, and that healing time is correlated with the ulcer cause and size.


Assuntos
Terapia a Laser , Úlcera Cutânea/radioterapia , Cicatrização/efeitos da radiação , Adulto , Análise de Variância , Doença Crônica , Intervalos de Confiança , Relação Dose-Resposta à Radiação , Feminino , Hélio , Humanos , Masculino , Pessoa de Meia-Idade , Neônio , Úlcera Cutânea/etiologia , Úlcera Cutânea/patologia , Resultado do Tratamento
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