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1.
Clin Exp Immunol ; 181(3): 385-400, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25959571

RESUMO

Biopharmaceuticals (BPs) represent a rapidly growing class of approved and investigational drug therapies that is contributing significantly to advancing treatment in multiple disease areas, including inflammatory and autoimmune diseases, genetic deficiencies and cancer. Unfortunately, unwanted immunogenic responses to BPs, in particular those affecting clinical safety or efficacy, remain among the most common negative effects associated with this important class of drugs. To manage and reduce risk of unwanted immunogenicity, diverse communities of clinicians, pharmaceutical industry and academic scientists are involved in: interpretation and management of clinical and biological outcomes of BP immunogenicity, improvement of methods for describing, predicting and mitigating immunogenicity risk and elucidation of underlying causes. Collaboration and alignment of efforts across these communities is made difficult due to lack of agreement on concepts, practices and standardized terms and definitions related to immunogenicity. The Innovative Medicines Initiative (IMI; www.imi-europe.org), ABIRISK consortium [Anti-Biopharmaceutical (BP) Immunization Prediction and Clinical Relevance to Reduce the Risk; www.abirisk.eu] was formed by leading clinicians, academic scientists and EFPIA (European Federation of Pharmaceutical Industries and Associations) members to elucidate underlying causes, improve methods for immunogenicity prediction and mitigation and establish common definitions around terms and concepts related to immunogenicity. These efforts are expected to facilitate broader collaborations and lead to new guidelines for managing immunogenicity. To support alignment, an overview of concepts behind the set of key terms and definitions adopted to date by ABIRISK is provided herein along with a link to access and download the ABIRISK terms and definitions and provide comments (http://www.abirisk.eu/index_t_and_d.asp).


Assuntos
Hipersensibilidade a Drogas/prevenção & controle , Drogas em Investigação/normas , Guias como Assunto/normas , Terminologia como Assunto , Alergia e Imunologia/normas , Hipersensibilidade a Drogas/imunologia , Indústria Farmacêutica/organização & administração , Indústria Farmacêutica/normas , Drogas em Investigação/efeitos adversos , Drogas em Investigação/uso terapêutico , Humanos , Inovação Organizacional , Política Organizacional , Padrões de Referência
2.
J Infect Dis ; 205(5): 718-24, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22238471

RESUMO

We performed a genome-wide association study comparing a cohort of 144 human immunodeficiency virus (HIV type 1-infected, untreated white long-term nonprogressors (LTNPs) with a cohort of 605 HIV-1-infected white seroconverters. Forty-seven single-nucleotide polymorphisms (SNPs), located from class I to class III major histocompatibility complex (MHC) subregions, show statistical association (false discovery rate, <0.05) with the LTNP condition, among which 5 reached genome-wide significance after Bonferonni correction. The MHC LTNP-associated SNPs are ordered in ≥4 linkage disequilibrium blocks; interestingly, an MHC class III linkage disequilibrium block (defined by the rs9368699 SNP) seems specific to the LTNP phenotype.


Assuntos
Progressão da Doença , Genes MHC Classe I/genética , Infecções por HIV/genética , HIV-1 , Polimorfismo de Nucleotídeo Único , Proteínas de Ligação a DNA/genética , Frequência do Gene , Estudo de Associação Genômica Ampla , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Complexo Principal de Histocompatibilidade/genética , RNA Longo não Codificante , RNA não Traduzido , Fatores de Tempo , Fatores de Transcrição/genética
3.
Biometrics ; 66(1): 301-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19432790

RESUMO

Pharmacovigilance systems aim at early detection of adverse effects of marketed drugs. They maintain large spontaneous reporting databases for which several automatic signaling methods have been developed. One limit of those methods is that the decision rules for the signal generation are based on arbitrary thresholds. In this article, we propose a new signal-generation procedure. The decision criterion is formulated in terms of a critical region for the P-values resulting from the reporting odds ratio method as well as from the Fisher's exact test. For the latter, we also study the use of mid-P-values. The critical region is defined by the false discovery rate, which can be estimated by adapting the P-values mixture model based procedures to one-sided tests. The methodology is mainly illustrated with the location-based estimator procedure. It is studied through a large simulation study and applied to the French pharmacovigilance database.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Algoritmos , Interpretação Estatística de Dados , Sistemas de Apoio a Decisões Clínicas , Reações Falso-Positivas , Reconhecimento Automatizado de Padrão/métodos , Humanos
4.
MAbs ; 12(1): 1725369, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32063088

RESUMO

Therapeutic proteins and emerging gene and cell-based therapies are attractive therapeutic tools for addressing unmet medical needs or when earlier conventional treatment approaches failed. However, the development of an immune response directed against therapeutic agents is a significant concern as it occurs in a substantial number of cases across products and indications. The specific anti-drug antibodies that develop can lead to safety adverse events as well as inhibition of drug activity or accelerated clearance, both phenomena resulting in loss of treatment efficacy. The European Immunogenicity Platform (EIP) is a meeting place for experts and newcomers to the immunogenicity field, designed to stimulate discussion amongst scientists across industry and academia, encourage interactions with regulatory agencies and share knowledge and the state-of-the-art of immunogenicity sciences with the broader scientific community. Here we report on the main topics covered during the EIP 10th Open Symposium on Immunogenicity of Biopharmaceuticals held in Lisbon, 26-27 February 2019, and the 1-d training course on practical and regulatory aspects of immunogenicity held ahead of the conference. These main topics included immunogenicity testing, clinical relevance of immunogenicity, immunogenicity prediction, regulatory aspects, tolerance induction as a mean to mitigate immunogenicity and immunogenicity in the context of gene therapy.


Assuntos
Anticorpos/imunologia , Produtos Biológicos/imunologia , Animais , Europa (Continente) , Humanos
5.
J Clin Oncol ; 13(7): 1578-83, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7602346

RESUMO

PURPOSE: To screen for factors that might predict the risk of developing metachronous contralateral breast cancer (CBC), taking into account the influence of local or distant recurrence, and to assess the annual incidence of CBC. PATIENTS AND METHODS: Of 4,748 women with invasive unilateral breast cancer, clinical stage I to IIIa, treated between 1981 and 1987, 282 metachronous CBCs were diagnosed. Due to competing risks between the occurrence of CBC and other events, several options for multivariate analysis were considered. RESULTS: The median follow-up time was 80 months (range, 1 to 158). The cumulative rate of CBC was 4.1% +/- 0.3% at 5 years, and the annual incidence rate of CBC increased slowly, while the risk of local recurrence and metastases decreased after the fourth year. Whichever model we chose, age less than 55 years (relative risk [RR] = 1.40) at the time of diagnosis of the first breast cancer, as well as the presence of lobular type carcinoma (RR = 1.50), was associated with an increased risk of developing a tumor in the contralateral breast. Adjuvant chemotherapy significantly decreased (RR = 0.54) the risk of CBC. CONCLUSION: Lobular histology and age less than 55 years are found to increase the risk of CBC, while adjuvant chemotherapy significantly decreased the risk of CBC. The progressive rise in the annual incidence rates of CBC, together with the absence of a link between clinical prognostic factors of the first cancer and CBC, suggested that CBC can be considered as a second primary breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias Primárias Múltiplas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Primárias Múltiplas/mortalidade , Neoplasias Primárias Múltiplas/patologia , Fatores de Risco , Taxa de Sobrevida
6.
J Clin Oncol ; 19(11): 2778-87, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11387348

RESUMO

PURPOSE: To assess the prognostic value of thymidine kinase (TK), an enzyme involved in the DNA synthesis salvage pathway, relative to other prognostic factors in primary breast cancer. PATIENTS AND METHODS: This retrospective study involved 1,692 patients with operable breast cancer treated in six institutions (median follow-up, 82 months). Among the 857 node-negative patients, 135 received adjuvant chemotherapy (fluorouracil, doxorubicin, cyclophosphamide [FAC] or fluorouracil, etoposide, and cisplatin [FEC]). TK was assayed in cytosol with a quantitative radioenzymatic technique. Disease-specific survival (DSS), local recurrence-free interval (LRI), and distant-relapse-free interval (DRI) were investigated. RESULTS: High TK levels were associated with large tumor size, high histologic grade, and steroid hormone receptor negativity. Univariate analysis of the entire data set showed that high TK levels were related to shorter DSS (P < 10(-5)), LRI (P < 10(-3)), and DRI (P < 10(-5)). In time-dependent Cox models, high TK levels remained an independent predictor of the three outcomes, both in the overall population and in node-negative patients, although its prognostic value decreased over time. In node-negative patients, the introduction of an interaction term in multivariate analysis suggested that chemotherapy was more efficacious for patients who had tumors with high TK contents. In node-positive patients, high TK levels were related only to an increased risk of LRI. CONCLUSION: High TK values are an important risk factor in node-negative patients and seem to be associated with a beneficial effect of adjuvant FAC or FEC in patients who received adjuvant chemotherapy. The rationale of chemotherapy for patients with slowly proliferating tumors has to be discussed from a risk-benefit point of view.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Timidina Quinase/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Ciclofosfamida/administração & dosagem , Progressão da Doença , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
7.
J Clin Oncol ; 22(15): 3133-8, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15284265

RESUMO

PURPOSE: To determine the response rate of low-grade oligodendroglial tumors (LGOT) to temozolomide (TMZ) as initial treatment and to evaluate the predictive value of chromosome 1p deletion on the radiologic response. PATIENTS AND METHODS: Adult patients with pathologically proven LGOT with progressive disease on magnetic resonance imaging (MRI) were eligible for the study. TMZ was administered at the starting dose of 200 mg/m2/d for 5 days, repeated every 28 days. Response was evaluated clinically and by central review of MRIs. Chromosome 1p and 19q deletions were detected by the loss of heterozygosity technique. RESULTS: Sixty consecutive patients were included in the study. At the time of analysis, the median number of TMZ cycles delivered was 11. Clinically, 51% of patients improved, particularly those with uncontrolled epilepsy. The objective radiologic response rate was 31% (17% partial response and 14% minor response), whereas 61% of patients had stable disease and 8% experienced disease progression. The median time to maximum tumor response was 12 months (range, 5 to 20 months). Myelosuppression was the most frequent side effect, with grade 3 to 4 toxicity in 8% of patients. Loss of chromosome 1p was associated with objective tumor response (P < .004). CONCLUSION: TMZ is well tolerated and provides a substantial rate of response in LGOT. Chromosome 1p loss is correlated with radiographic response and could be a helpful marker for guiding therapeutic decision making in LGOT.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Astrocitoma/tratamento farmacológico , Astrocitoma/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/genética , Adulto , Idoso , Feminino , Humanos , Perda de Heterozigosidade , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Temozolomida
8.
Neurology ; 53(8): 1719-23, 1999 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-10563618

RESUMO

OBJECTIVE: To evaluate 1) the effect of the tumor treatment on the clinical course of paraneoplastic encephalomyelitis (PEM) with anti-Hu antibodies, 2) the impact of immunotherapy on the tumor evolution, and 3) the outcome of the small cell lung cancer (SCLC) of PEM patients compared with that of patients without PEM. METHODS: The authors retrospectively analyzed 51 PEM patients (42 with SCLC, 9 with other tumors) who received antineoplastic treatment with (25 patients) or without (26) concomitant immunotherapy. Tumor response was assessed at the end of the antineoplastic treatment. Progression of PEM was defined as a change of at least 1 point in the Rankin scale measured at the onset and at the end of the tumor treatment. To evaluate the outcome of SCLC, 27 PEM patients with SCLC were matched one-to-one with SCLC patients without PEM for age, performance status, tumor stage, and type of antineoplastic treatment. RESULTS: Thirty-six (70%) patients were neurologically stable at the end of the tumor treatment. In a logistic regression analysis, tumor complete response was the only predictor of PEM stabilization (OR 7.07; 95% CI 1.68 to 29.76; p = 0.006). Immunotherapy did not modify the outcome of the tumor and PEM. Median survival was similar in SCLC patients with and without PEM, but the probability of survival at 30 months was higher in PEM patients with SCLC (OR 5.26; 95% CI 1.0004 to 27.6902; p = 0.03). CONCLUSIONS: Complete response of the tumor seems to have a favorable influence on the course of paraneoplastic encephalomyelitis (PEM). Concomitant immunotherapy does not adversely affect the tumor outcome. The small cell lung cancer of PEM patients may have a slightly better evolution than that of patients without PEM.


Assuntos
Anticorpos/análise , Encefalomielite/imunologia , Encefalomielite/terapia , Imunoterapia , Proteínas do Tecido Nervoso , Síndromes Paraneoplásicas/imunologia , Síndromes Paraneoplásicas/terapia , Proteínas de Ligação a RNA/imunologia , Adulto , Idoso , Carcinoma de Células Pequenas/complicações , Carcinoma de Células Pequenas/terapia , Progressão da Doença , Proteínas ELAV , Encefalomielite/complicações , Feminino , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Síndromes Paraneoplásicas/complicações , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
9.
Neurology ; 57(7): 1278-81, 2001 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-11591848

RESUMO

OBJECTIVE: To identify different genetic molecular profiles in oligodendrogliomas and to evaluate their prognostic significance. METHODS: The main genetic alterations reported in glial tumors were investigated in 26 oligodendrogliomas (10 World Health Organization grade II and 16 World Health Organization grade III). Correlation between identified molecular changes and pathologic grade or clinical course was subsequently analyzed using univariate and multivariate statistical analyses. RESULTS: Loss of heterozygosity (LOH) on chromosome 1p, 19q, and 10; P16/CDKN2A homozygous deletion; EGFR (epidermal growth factor receptor) amplification; and TP53 and PTEN mutations were observed in 14 (54%), 15 (58%), 9 (35%), 7 (27%), 5 (19%), 1 (4%), and 0 cases. LOH 1p and 19q were tightly associated (p < 0.0001). A mutual exclusion was found between LOH 1p/19q and EGFR amplification (p = 0.01), P16/CDKN2A deletions (p = 0.001), or LOH on 10q (p = 0.03), suggesting the existence of distinct genetic subsets in oligodendrogliomas. On univariate analysis, age <50 years (p = 0.002) and LOH 1p (p = 0.01) were associated with a longer progression-free survival (PFS) whereas LOH 10q (p = 0.03) and EGFR amplification (p = 0.007) were associated with a worse PFS. In multivariate analyses, age <50 years (p = 0.001) and LOH 1p (p = 0.006) remained independent predictive factors for PFS. CONCLUSION: These results provide evidence for two alternative molecular pathways of progression in oligodendrogliomas. The first one is associated with loss of 1p and 19q and the second one with P16/CDKN2A deletion, 10q loss, and EGFR amplification. The findings confirm the value of loss of 1p as predictor of longer progression-free survival; in addition, the study demonstrates the unfavorable impact of 10q loss and EGFR amplification on the prognosis.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Heterogeneidade Genética , Oligodendroglioma/genética , Oligodendroglioma/mortalidade , Proteínas Supressoras de Tumor , Adulto , Idoso , Neoplasias Encefálicas/patologia , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 10 , Cromossomos Humanos Par 19 , Progressão da Doença , Intervalo Livre de Doença , Receptores ErbB/genética , Genes p16/genética , Genes p53/genética , Humanos , Perda de Heterozigosidade , Pessoa de Meia-Idade , Análise Multivariada , Oligodendroglioma/patologia , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases/genética , Valor Preditivo dos Testes , Prognóstico
10.
Int J Radiat Oncol Biol Phys ; 36(3): 615-21, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8948346

RESUMO

PURPOSE: To determine which clinical, biological, or treatment-related factors of the first and second primary breast cancers influenced the outcome following contralateral breast carcinoma (CBC). METHODS AND MATERIALS: By August 1994, 319 of 6406 patients with clinical Stage 0 to III breast carcinoma treated between 1981 and 1987 at Institut Curie had developed a second breast cancer that was diagnosed more than 6 months following ipsilateral breast cancer. Of these 319 patients, 235 had a CBC as the first recurrent event and constitute the study population. Comparisons of first and second breast tumor characteristics were done using Fisher's exact test. Survival distributions from the date of CBC were compared by the log-rank test. Prognostic factors for local relapses, distant relapses, and survival after CBC were assessed by univariate and multivariate analysis using the Cox proportional hazards model. RESULTS: The diagnosis of CBC was more frequently guided by mammographies than for ipsilateral tumors (p < 0.0001). The proportion of early stage tumors < or = T1 was significantly higher in the opposite breast as compared to the the first primary tumor (p < 0.0001). A greater rate of noninvasive tumors was observed in CBCs (p = 0.0003). Median follow-up time from the diagnosis of CBC was 54 months (1-137). Five-year survival following CBC was 79% (+/- 6). Five-year local (CBC breast or chest wall) and distant failure rates were 15 and 24%, respectively. Time interval to the occurrence of CBC (< 2 years, 2-5 years, > 5 years) had no influence on survival. Cox model analysis showed that the risk factors for distant metastases were stage and progesterone receptor levels of the contralateral tumor. The risk of distant failure in CBC was not influenced by the extent of surgery. CONCLUSIONS: In this selected population of CBCs as first recurrent events, a follow-up policy based on clinical examination and annual mammography enabled the detection of CBCs at an earlier stage than the primary ipsilateral cancer. The outcome after CBC was determined only by the characteristics of the contralateral tumor. Breast-conserving treatment should be recommended when it is feasible. Adjuvant chemotherapy should be delivered according to the same criteria as the primary tumor.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Segunda Neoplasia Primária , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/química , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/radioterapia , Carcinoma Ductal de Mama/secundário , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Segunda Neoplasia Primária/química , Segunda Neoplasia Primária/diagnóstico por imagem , Segunda Neoplasia Primária/patologia , Radiografia , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Recidiva
11.
Biochem Pharmacol ; 61(7): 867-76, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11274973

RESUMO

Potentiation of the cytotoxic activity of 5-fluorouracil (FUra) by folinic acid (5-HCO-H4folate) is due to elevation of the methylene tetrahydrofolate (CH2-H4folate) level, which increases the stability of the ternary complex of thymidylate synthase (TS), fluorodeoxyuridine monophosphate, and CH2-H4folate that inactivates the TS. Methionine deprivation results in the production of tetrahydrofolate (H4folate) and, subsequently, CH2-H4folate from methyl tetrahydrofolate, as a consequence of the induction of methionine synthesis. We hypothesized that the efficacy of FUra could be augmented by the combination of high-concentration 5-HCO-H4folate and recombinant methioninase (rMETase), a methionine-cleaving enzyme. Studies in vitro were performed with the cell line CCRF-CEM. Cytotoxic synergism of FUra + rMETase and FUra + 5-HCO-H4folate + rMETase was demonstrated with the combination index throughout a broad concentration range of FUra and rMETase. A subcytotoxic concentration of rMETase reduced the IC50 of FUra by a factor of 3.6, and by a factor of 7.5, in the absence and in the presence of 5-HCO-H4folate, respectively. 5-HCO-H4folate increased the intracellular concentrations of CH2-H4folate and H4folate from their baseline levels. Concentrations of folates were not changed by exposure to rMETase. Levels of free TS in cells treated with FUra + 5-HCO-H4folate and with FUra + rMETase were lower than those in cells exposed to FUra alone. The decrease of TS was still more pronounced in cells treated with FUra + 5-HCO-H4folate + rMETase. The synergism described in this study will be a basis for further exploration of combinations of fluoropyrimidines, folates, and rMETase.


Assuntos
Liases de Carbono-Enxofre/farmacologia , Fluoruracila/farmacologia , Leucovorina/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Humanos , Metionina/metabolismo , Proteínas Recombinantes/farmacologia , Tetra-Hidrofolatos/metabolismo , Timidilato Sintase/metabolismo , Células Tumorais Cultivadas
12.
Am J Clin Pathol ; 110(5): 607-12, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9802345

RESUMO

We reviewed 72 primary central nervous system lymphomas occurring in immunocompetent patients. The cases were reviewed for clinical data, histology, immunophenotype, bcl-2 and p53 expression, and Epstein-Barr virus association. Follow-up was available for 40 patients included in the Groupe Ouest Est d'étude des Leucénies et Autres Maladies du Sang (GOELAMS) lymphomes cérébraux primitifs (LCP 88) trial. Each diagnosis, requiring a consensus among at least 3 pathologists, was performed according to the recent Revised European-American Lymphoma classification and equivalents in the updated Kiel classification. Tumors were predominantly classified as diffuse large B-cell lymphomas. There were 3 T-cell lymphomas and 1 Hodgkin lymphoma. The proteins bcl-2 and p53 were expressed in 35% and 16% of the tested cases, respectively. Epstein-Barr virus was not found by in situ hybridization except in the case classfied as a cerebral localization of Hodgkin disease. No significant association was found between subtypes, bcl-2 or p53 expression, and patient survival. From the standpoint of their biologic characteristics, primary central nervous system lymphomas are very similar to systemic diffuse large B-cell lymphomas. In contrast to AIDS-related primary central nervous system lymphomas, primary central nervous system lymphomas are rarely associated with Epstein-Barr virus and in immunocompetent patients they express bcl-2 at a relatively low rate.


Assuntos
Neoplasias do Sistema Nervoso Central/patologia , Imunocompetência , Linfoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/imunologia , Neoplasias do Sistema Nervoso Central/microbiologia , Feminino , Herpesvirus Humano 4/genética , Doença de Hodgkin/imunologia , Doença de Hodgkin/patologia , Humanos , Imuno-Histoquímica , Imunofenotipagem , Hibridização In Situ , Linfoma/imunologia , Linfoma/microbiologia , Linfoma de Células B/imunologia , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/patologia , Linfoma de Células T/imunologia , Linfoma de Células T/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/análise , RNA Viral/análise , Proteína Supressora de Tumor p53/análise
13.
Bull Cancer ; 83(10): 870-6, 1996 Oct.
Artigo em Francês | MEDLINE | ID: mdl-8952638

RESUMO

Metachronous contralateral breast cancer (CBC) is defined as a tumour in the opposite breast which was diagnosed more than 6 months following the detection of the first cancer. We screened, for factors that might predict the risk of developing CBC, a cohort series of 4748 women who had invasive unilateral breast cancer, clinical stage I-IIIa and had been treated at Institut Curie (Paris) between 1981 and 1987. Two hundred and eighty two CBC had been diagnosed with a median follow-up of 80 months. The cumulative rate of CBC was 4.1% at 5 years. We studied relationships between CBC and family history of breast cancer, age at diagnosis of first cancer, menopausal status, tumour size, node involvement, histological type, Scarff Bloom Richardson grade, estrogen and progesterone receptor measurements, as well as the type of primary treatment. Due to competing risks between the occurrence of CBC, local recurrence and metastasis, several options for multivariate analysis were considered. In model I, we focused on the occurrence of CBC, and ignored others events. In model II, only CBC, if first site of failure was taken into account, and in model III we considered others events as time-dependant covariates. Whichever the model we chose, age less than 55 years (RR = 1.40) as well as the presence of lobular type carcinoma (RR = 1.50), were associated with an increased risk of developing a tumour in the contralateral breast. In contrast, the risk of CBC was significantly decreased by adjuvant chemotherapy (RR = 0.54). Neither tumor stage or lymph node involvement influence the risk of CBC. These results suggested that CBC is a second primary breast cancer.


Assuntos
Neoplasias da Mama , Segunda Neoplasia Primária , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/secundário , Neoplasias da Mama/terapia , Estudos de Coortes , Terapia Combinada , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Segunda Neoplasia Primária/diagnóstico , Segunda Neoplasia Primária/epidemiologia , Estudos Retrospectivos , Fatores de Risco
14.
Bull Cancer ; 85(4): 347-52, 1998 Apr.
Artigo em Francês | MEDLINE | ID: mdl-9752299

RESUMO

We screened for the prognostic value of estrogen receptor (ER) and progesterone receptor (PR) through a multicentric study of 2,257 operable breast cancer patients who did not received adjuvant therapy. Three hundred and seven local-regional recurrences, 105 metachronous contralateral breast cancer, 589 metastases and 537 deaths from cancer had been diagnosed with a median follow-up of 8.5 years. A total of 69% of the tumors were ER positive and 54% PR positive. For statistical analysis, 1,665 patients were studied because of complete clinical and biological data. In univariate analysis, ER and PR status were of prognostic value for the metastases-free interval (MFI) and the overall survival (OS). In multivariate analysis (Cox proportional hazard model), only the ER status showed a significant difference between positive and negative groups regarding the MFI and OS. By using Cox regression model with time-dependent covariates, we show that the predictive value of ER status of the primary tumor decreases by approximately 20% per year, losing its significance after 8 years of follow-up. These results show that ER and PR status have a relatively limited predictive value and their major interest remain in the domain of therapeutic decision.


Assuntos
Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Adulto , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Risco , Análise de Sobrevida
15.
Rev Epidemiol Sante Publique ; 52(6): 523-37, 2004 Dec.
Artigo em Francês | MEDLINE | ID: mdl-15741915

RESUMO

BACKGROUND: When analysing data which simultaneously implicate a large number of statistical tests, one of the main problems is to take into account the multiplicity of these tests. The huge amount of comparisons done in studies of which the aim is to detect, using microarray, genes whose transcriptional changes are related to a biological or clinical outcome leads to a renewed interest for the multiple comparisons problem. However, this problem concerns many other fields such as psychometry, epidemiology, genetics. RESULTS: First, we introduce the multiple comparison framework. Then, we present the main procedures based on a global error rate called the "Family Wise Error Rate" (FWER) and those based on a false discovery rate expectancy (the "False Discovery Rate" (FDR) and the "positive False Discovery Rate" (pFDR)). Next, we apply the different procedures on a real dataset from a breast carcinoma study. Finally, we discuss the main results and we present guidelines for the use of these procedures.


Assuntos
Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reações Falso-Positivas , Genótipo , Humanos , Fenótipo , Análise de Sequência/métodos
16.
Rev Epidemiol Sante Publique ; 47(6): 619-25, 1999 Dec.
Artigo em Francês | MEDLINE | ID: mdl-10673596

RESUMO

Analysis of survival of patients with cancer sets particular epidemiological and statistical problems, especially when one wants to take into account metastasis or local recurrences. Cox's model does not allow modeling multiple events. Wei et al. have proposed an extension of Cox's model, by formulating the marginal distributions of multivariate failure times, which allows testing covariates effects on different events. We applied these methods to data from the Registry of Digestive Tumors of Burgundy, France. Prognostic factors of recurrence are rectal location of tumor and advanced stage at diagnosis. Prognostic factors of death are male gender, age greater than 75, rectal location and advanced stages. However, relative risk of recurrence for advanced stages is significantly greater than relative risk of death (p=4.10(-3)), while tumor location has the same influence on the two events.


Assuntos
Neoplasias Colorretais/mortalidade , Modelos Estatísticos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/mortalidade , Prognóstico , Análise de Sobrevida
17.
Stat Med ; 18(14): 1801, 1999 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-10407250
18.
Stat Med ; 18(14): 1791-800; discussion 1801, 1999 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-10407249

RESUMO

In analysing a clinical trial with the logrank test, the hazards between the two groups are usually assumed to be proportional. Nevertheless, this hypothesis is no longer valid with unobserved covariates. As a consequence, there is a loss of power of the logrank test for testing the null hypothesis H(0) of no treatment effect. We propose a test suited for taking into account unobserved covariates. The proposed approach is based on a proportional hazard frailty model whereby the omitted covariates are considered as an unobserved frailty variable. The procedure is as follows. In a first step, the weighted logrank test optimal for testing H(0) against a general proportional hazard frailty model is obtained and its specialization for a gamma frailty variable is derived. In a second step, the proposed test is obtained by combining the maximin efficiency robustness principle and the gamma frailty distribution properties. Simulation studies investigate the power properties of the test for different frailty distributions. A breast cancer clinical trial is analysed as an example. The proposed test might be recommended rather than the logrank for practical situations in which one expects heterogeneity related to omitted covariates.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Ensaios Clínicos como Assunto/estatística & dados numéricos , Simulação por Computador , Modelos Biológicos , Quimioterapia Adjuvante , Ensaios Clínicos como Assunto/métodos , Feminino , Humanos , Modelos Lineares , Método de Monte Carlo , Modelos de Riscos Proporcionais , Análise de Sobrevida
19.
Stat Med ; 22(6): 931-40, 2003 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-12627410

RESUMO

In recent years randomized trials designed to establish non-inferiority of a new treatment as compared to a standard one have been more widely used. Two-sample statistics have been proposed for this equivalence testing problem. However, they are not suited to situations where a long-term survivor fraction is expected. In this paper we propose a score test designed for establishing non-inferiority for the new treatment as compared to the standard one while assuming identical long-term survivor rates. Simulations results show that the proposed statistic has satisfactory size and power as long as certain restricting conditions are verified. A breast cancer trial is analysed as an example.


Assuntos
Modelos Biológicos , Modelos Estatísticos , Equivalência Terapêutica , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Simulação por Computador , Feminino , Humanos , Linfonodos/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Análise de Sobrevida
20.
Biometrics ; 57(3): 844-52, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11550936

RESUMO

In the two-sample comparison of survival times with long-term survivors, the overall difference between the two distributions reflects differences occurring in early follow-up for susceptible subjects and in long-term follow-up for nonsusceptible subjects. In this setting, we propose statistics for testing (i) no overall, (ii) no short-term, and (iii) no long-term difference between the two distributions to be compared. The statistics are derived as follows. A semiparametric model is defined that characterizes a short-term effect and a long-term effect. By approximating this model about no difference in early survival, a time-dependent proportional hazards model is obtained. The statistics are obtained from this working model. The asymptotic distributions of the statistics for testing no overall or no short-term effects are ascertained, while that of the statistic for testing no long-term effect is valid only when the short-term effect is small. Simulation studies investigate the power properties of the proposed tests for different configurations. The results show the interesting behavior of the proposed tests for situations where a short-term effect is expected. An example investigating the impact of progesterone receptors status on local tumor relapse for patients with early breast cancer illustrates the use of the proposed tests.


Assuntos
Biometria , Análise de Sobrevida , Neoplasias da Mama/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Recidiva Local de Neoplasia/metabolismo , Modelos de Riscos Proporcionais , Estudos Prospectivos , Receptores de Progesterona/metabolismo , Distribuições Estatísticas
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