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1.
JAMA Netw Open ; 6(10): e2337494, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37847504

RESUMO

Importance: Selenium and vitamin E have been identified as promising agents for the chemoprevention of recurrence and progression of non-muscle-invasive bladder cancer. Objective: To determine whether selenium and/or vitamin E may prevent disease recurrence in patients with newly diagnosed NMIBC. Design, Setting, and Participants: This multicenter, prospective, double-blinded, placebo-controlled, 2 × 2 factorial randomized clinical trial included patients with newly diagnosed NMIBC recruited from 10 secondary or tertiary care hospitals in the UK. A total of 755 patients were screened for inclusion; 484 did not meet the inclusion criteria, and 1 declined to participate. A total of 270 patients were randomly assigned to 4 groups (selenium plus placebo, vitamin E plus placebo, selenium plus vitamin E, and placebo plus placebo) in a double-blind fashion between July 17, 2007, and October 10, 2011. Eligibility included initial diagnosis of NMIBC (stages Ta, T1, or Tis); randomization within 12 months of first transurethral resection was required. Interventions: Oral selenium (200 µg/d of high-selenium yeast) and matched vitamin E placebo, vitamin E (200 IU/d of d-alfa-tocopherol) and matched selenium placebo, selenium and vitamin E, or placebo and placebo. Main Outcome and Measures: Recurrence-free interval (RFI) on an intention-to-treat basis (analyses completed on November 28, 2022). Results: The study randomized 270 patients (mean [SD] age, 68.9 [10.4] years; median [IQR] age, 69 [63-77] years; 202 male [75%]), with 65 receiving selenium and vitamin E placebo, 71 receiving vitamin E and selenium placebo, 69 receiving selenium and vitamin E, and 65 receiving both placebos. Median overall follow-up was 5.5 years (IQR, 5.1-6.1 years); 228 patients (84%) were followed up for more than 5 years. Median treatment duration was 1.5 years (IQR, 0.9-2.5 years). The study was halted because of slow accrual. For selenium (n = 134) vs no selenium (n = 136), there was no difference in RFI (hazard ratio, 0.92; 95% CI, 0.65-1.31; P = .65). For vitamin E (n = 140) vs no vitamin E (n = 130), there was a statistically significant detriment to RFI (hazard ratio, 1.46; 95% CI, 1.02-2.09; P = .04). No significant differences were observed for progression-free interval or overall survival time with either supplement. Results were unchanged after Cox proportional hazards regression modeling to adjust for known prognostic factors. In total, 1957 adverse events were reported; 85 were serious adverse events, and all were considered unrelated to trial treatment. Conclusions and Relevance: In this randomized clinical trial of selenium and vitamin E, selenium supplementation did not reduce the risk of recurrence in patients with NMIBC, but vitamin E supplementation was associated with an increased risk of recurrence. Neither selenium nor vitamin E influenced progression or overall survival. Vitamin E supplementation may be harmful to patients with NMIBC, and elucidation of the underlying biology is required. Trial Registration: isrctn.org Identifier: ISRCTN13889738.


Assuntos
Neoplasias não Músculo Invasivas da Bexiga , Selênio , Neoplasias da Bexiga Urinária , Humanos , Masculino , Idoso , Vitamina E/uso terapêutico , Selênio/uso terapêutico , Estudos Prospectivos , Recidiva Local de Neoplasia/prevenção & controle , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias da Bexiga Urinária/prevenção & controle , Neoplasias da Bexiga Urinária/tratamento farmacológico
2.
BJU Int ; 124(6): 984-991, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31077532

RESUMO

OBJECTIVES: To quantify the health-related quality of life (HRQoL) of patients with bladder cancer around the time of diagnosis and to test the hypotheses of a two-factor model for the HRQoL questionnaire QLQ-C30. METHODS: From participants in the Bladder Cancer Prognoses Programme, a multicentre cohort study, sociodemographic data were collected using semi-structured face-to-face interviews. Answers to the QLQ-C30 were transformed into a scale from 0 to 100. HRQoL data were analysed in multivariate analyses. The hypothesized two-factor (Physical and Mental Health) domain structure of the QLQ-C30 was also tested with confirmatory factor analyses (CFA). RESULTS: A total of 1160 participants (78%) completed the questionnaire after initial visual diagnosis and before pathological confirmation. Despite non-muscle-invasive bladder cancer (NMIBC) being associated with a higher HRQoL than carcinoma invading bladder muscle, only the domain Role Functioning was clinically significantly better in patients with NMIBC. Age, gender, bladder cancer stage and comorbidity all had a significant influence on QLQ-C30 scores. The CFA showed an overall good fit of the hypothesized two-factor model. CONCLUSION: This study identified a baseline reference value for HRQoL for patients with bladder cancer, which allows better evaluation of any changes in HRQoL as disease progresses or after treatment. In addition, a two-factor (Physical and Mental Health) model was developed for the QLQ-C30.


Assuntos
Qualidade de Vida , Neoplasias da Bexiga Urinária , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Nível de Saúde , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Inquéritos e Questionários , Fatores de Tempo , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/psicologia
3.
World J Urol ; 37(12): 2747-2753, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30903352

RESUMO

BACKGROUND: Due to the high risk of recurrence of non-muscle invasive bladder cancer, all patients undergo regular cystoscopic surveillance for early detection. As cystoscopy is invasive, costly and increases the burden of the disease considerably, there is significant ongoing research and development into non-invasive urinary biomarker substitutes. This study aims to assess the level of sensitivity required before patients accept a new urinary biomarker. METHODS: We studied the preferences for a hypothetical diagnostic urinary biomarker and compared this to usual care (cystoscopy) at different levels of sensitivity among 437 patients with bladder cancer (354 men and 83 women) from the UK Bladder Cancer Prognosis Programme. A standard gamble approach was used to estimate the minimally acceptable sensitivity (MAS) of the new biomarker. Additionally, non-parametric statistical analyses were performed to investigate the association between surveillance preference and various patient characteristics. RESULTS: Almost half of patients (183, 43%) would not replace cystoscopy with a urinary biomarker unless it was 100% sensitive. The median MAS was 99.9999%, and nearly 85% of patients demanded a sensitivity of at least 99% before preferring a urinary biomarker test over cystoscopy. These results were consistent across all patient characteristics and demographic categories. CONCLUSIONS: Our results indicate that patients demand urinary biomarkers as sensitive as cystoscopy before they would be willing to forego cystoscopy for bladder cancer surveillance.


Assuntos
Biomarcadores Tumorais/urina , Cistoscopia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/urina , Preferência do Paciente , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Efeitos Psicossociais da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Sensibilidade e Especificidade
4.
Eur Urol ; 75(1): 63-71, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30274699

RESUMO

BACKGROUND: There is no effective intravesical second-line therapy for non-muscle-invasive bladder cancer (NMIBC) when bacillus Calmette-Guérin (BCG) fails. OBJECTIVE: To compare disease-free survival time (DFS) between radiofrequency-induced thermo-chemotherapy effect (RITE) and institutional standard second-line therapy (control) in NMIBC patients with recurrence following induction/maintenance BCG. DESIGN, SETTINGS, AND PARTICIPANTS: Open-label, phase III randomised controlled trial accrued across 14 centres between May 2010 and July 2013 (HYMN [ClinicalTrials.gov: NCT01094964]). INTERVENTION: Patients were randomly assigned (1:1) to RITE (60min, 40mg mitomycin-C, 42±2°C) or control following stratification for carcinoma in situ (CIS) status (present/absent), therapy history (failure of previous induction/maintenance BCG), and treatment centre. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Primary outcome measures were DFS and complete response (CR) at 3 mo for the CIS at randomisation subgroup. Analysis was based on intention-to-treat. RESULTS AND LIMITATIONS: A total of 104 patients were randomised (48 RITE: 56 control). Median follow-up for the 31 patients without a DFS event was 36 mo. There was no significant difference in DFS between treatment arms (hazard ratio [HR] 1.33, 95% confidence interval [CI] 0.84-2.10, p=0.23) or in 3-mo CR rate in CIS patients (n=71; RITE: 30% vs control: 47%, p=0.15). There was no significant difference in DFS between treatment arms in non-CIS patients (n=33; RITE: 53% vs control: 24% at 24 mo, HR 0.50, 95% CI 0.22-1.17, p=0.11). DFS was significantly lower in RITE than in control in CIS with/without papillary patients (n=71; HR 2.06, 95% CI 1.17-3.62, p=0.01; treatment-subgroup interaction p=0.007). Disease progression was observed in four patients in each treatment arm. Adverse events and health-related quality of life between treatment arms were comparable. CONCLUSIONS: DFS was similar between RITE and control. RITE may be a second-line therapy for non-CIS recurrence following BCG failure; however, confirmatory trials are needed. RITE patients with CIS with/without papillary had lower DFS than control. HYMN highlights the importance of the control arm when evaluating novel therapies. PATIENT SUMMARY: This study did not show a difference in bladder cancer outcomes between microwave-heated chemotherapy and standard of care treatment. Papillary bladder lesions may benefit from microwave-heated chemotherapy treatment; however, more research is needed. Both treatments are similarly well tolerated.


Assuntos
Antineoplásicos/uso terapêutico , Vacina BCG/uso terapêutico , Mitomicina/uso terapêutico , Recidiva Local de Neoplasia/terapia , Terapia por Radiofrequência , Neoplasias da Bexiga Urinária/terapia , Administração Intravesical , Idoso , Idoso de 80 Anos ou mais , Carcinoma in Situ/patologia , Carcinoma in Situ/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
5.
Clin Cancer Res ; 23(24): 7440-7447, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28733440

RESUMO

The ever-increasing pace of development of novel therapies mandates efficient methodologies for assessment of their tolerability and activity. Evidence increasingly support the merits of model-based dose-finding designs in identifying the recommended phase II dose compared with conventional rule-based designs such as the 3 + 3 but despite this, their use remains limited. Here, we propose a useful tool, dose transition pathways (DTP), which helps overcome several commonly faced practical and methodologic challenges in the implementation of model-based designs. DTP projects in advance the doses recommended by a model-based design for subsequent patients (stay, escalate, de-escalate, or stop early), using all the accumulated information. After specifying a model with favorable statistical properties, we utilize the DTP to fine-tune the model to tailor it to the trial's specific requirements that reflect important clinical judgments. In particular, it can help to determine how stringent the stopping rules should be if the investigated therapy is too toxic. Its use to design and implement a modified continual reassessment method is illustrated in an acute myeloid leukemia trial. DTP removes the fears of model-based designs as unknown, complex systems and can serve as a handbook, guiding decision-making for each dose update. In the illustrated trial, the seamless, clear transition for each dose recommendation aided the investigators' understanding of the design and facilitated decision-making to enable finer calibration of a tailored model. We advocate the use of the DTP as an integral procedure in the co-development and successful implementation of practical model-based designs by statisticians and investigators. Clin Cancer Res; 23(24); 7440-7. ©2017 AACR.


Assuntos
Relação Dose-Resposta a Droga , Leucemia Mieloide Aguda/tratamento farmacológico , Modelos Estatísticos , Ensaios Clínicos como Assunto , Tomada de Decisões , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Leucemia Mieloide Aguda/patologia , Dose Máxima Tolerável
6.
BJU Int ; 119(4): 522-529, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27256016

RESUMO

OBJECTIVE: To evaluate the cost-effectiveness of adding zoledronic acid or strontium-89 to standard docetaxel chemotherapy for patients with castrate-refractory prostate cancer (CRPC). PATIENTS AND METHODS: Data on resource use and quality of life for 707 patients collected prospectively in the TRAPEZE 2 × 2 factorial randomised trial (ISRCTN 12808747) were used to assess the cost-effectiveness of i) zoledronic acid versus no zoledronic acid (ZA vs. no ZA), and ii) strontium-89 versus no strontium-89 (Sr89 vs. no Sr89). Costs were estimated from the perspective of the National Health Service in the UK and included expenditures for trial treatments, concomitant medications, and use of related hospital and primary care services. Quality-adjusted life-years (QALYs) were calculated according to patients' responses to the generic EuroQol EQ-5D-3L instrument, which evaluates health status. Results are expressed as incremental cost-effectiveness ratios (ICERs) and cost-effectiveness acceptability curves. RESULTS: The per-patient cost for ZA was £12 667, £251 higher than the equivalent cost in the no ZA group. Patients in the ZA group had on average 0.03 QALYs more than their counterparts in no ZA group. The ICER for this comparison was £8 005. Sr89 was associated with a cost of £13 230, £1365 higher than no Sr89, and a gain of 0.08 QALYs compared to no Sr89. The ICER for Sr89 was £16 884. The probabilities of ZA and Sr89 being cost-effective were 0.64 and 0.60, respectively. CONCLUSIONS: The addition of bone-targeting treatments to standard chemotherapy led to a small improvement in QALYs for a modest increase in cost (or cost-savings). ZA and Sr89 resulted in ICERs below conventional willingness-to-pay per QALY thresholds, suggesting that their addition to chemotherapy may represent a cost-effective use of resources.


Assuntos
Conservadores da Densidade Óssea/economia , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/secundário , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Estrôncio/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/economia , Análise Custo-Benefício , Intervalo Livre de Doença , Humanos , Masculino , Estudos Prospectivos , Qualidade de Vida , Compostos Radiofarmacêuticos/uso terapêutico , Reino Unido , Ácido Zoledrônico
7.
JAMA Oncol ; 2(4): 493-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26794729

RESUMO

IMPORTANCE: Bony metastatic castrate-refractory prostate cancer (CRPC) has a poor prognosis and high morbidity. Zoledronic acid (ZA) is commonly combined with docetaxel in practice but lacks evidence that combining is effective, and strontium-89 (Sr89) is generally used palliatively in patients unfit for chemotherapy. Phase 2 analysis of the TRAPEZE trial confirmed combining the agents was safe and feasible, and the objectives of phase 3 include assessment of the treatments on survival. OBJECTIVE: To determine clinical effectiveness and cost-effectiveness of combining docetaxel, ZA, and Sr89, all having palliative benefits and used in bony metastatic CRPC to control bone symptoms and, for docetaxel, to prolong survival. DESIGN, SETTING, AND PARTICIPANTS: The TRAPEZE trial is a 2 × 2 factorial trial comparing docetaxel alone or with ZA, Sr89, or both. A cohort of 757 participants were recruited between February 2005 and February 2012 from hospitals in the United Kingdom. Overall, 169 participants (45%) had received palliative radiotherapy, and the median (IQR) prostate-specific antigen level was 146 (51-354). Follow-ups were performed for at least 12 months. INTERVENTIONS: Up to 10 cycles of docetaxel alone; docetaxel with ZA; docetaxel with a single Sr89 dose after 6 cycles; or docetaxel with both ZA and Sr89. MAIN OUTCOMES AND MEASURES: Primary outcomes included clinical progression-free survival (CPFS) (pain progression, skeletal-related events [SREs], or death) and cost-effectiveness. Secondary outcomes included SRE-free interval, pain progression-free interval, total SREs, and overall survival (OS). RESULTS: Overall, of 757 participants, 349 (46%) completed docetaxel treatment. Median (IQR) age was 68 (63-73) years. Clinical progression-free survival did not reach statistical significance for either Sr89 or ZA. Cox regression analysis adjusted for all stratification variables showed benefit of Sr89 on CPFS (hazard ratio [HR], 0.85; 95% CI, 0.73-0.99; P = .03) and confirmed no effect of ZA (HR, 0.98; 95% CI, 0.85-1.14; P = .81); ZA had a significant effect on SRE-free interval (HR, 0.78; 95% CI, 0.65-0.95; P = .01). For OS, there was no effect of either Sr89 (HR, 0.92; 95% CI, 0.79-1.08; P = 0.34) or ZA (HR, 0.99; 95% CI, 0.84-1.16; P = 0.91). CONCLUSIONS AND RELEVANCE: Strontium-89 combined with docetaxel improved CPFS but did not improve OS, SRE-free interval, or total SREs; ZA did not improve CPFS or OS but did significantly improve median SRE-free interval and reduced total SREs by around one-third, suggesting a role as postchemotherapy maintenance therapy. TRIAL REGISTRATION: isrctn.com Identifier: ISRCTN12808747.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Idoso , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Intervalo Livre de Doença , Docetaxel , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Neoplasias da Próstata/mortalidade , Estrôncio/administração & dosagem , Estrôncio/efeitos adversos , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Ácido Zoledrônico
8.
Med Decis Making ; 36(3): 321-34, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26209474

RESUMO

BACKGROUND AND OBJECTIVES: Efforts to ensure that funded research represents "value for money" have led to increasing calls for the use of analytic methods in research prioritization. A number of analytic approaches have been proposed to assist research funding decisions, the most prominent of which are value of information (VOI) and prospective payback of research (PPoR). Despite the increasing interest in the topic, there are insufficient VOI and PPoR applications on the same case study to contrast their methods and compare their outcomes. We undertook VOI and PPoR analyses to determine the value of conducting 2 proposed research programs. The application served as a vehicle for identifying differences and similarities between the methods, provided insight into the assumptions and practical requirements of undertaking prospective analyses for research prioritization, and highlighted areas for future research. METHODS: VOI and PPoR were applied to case studies representing proposals for clinical trials in advanced non-small-cell lung cancer and prostate cancer. Decision models were built to synthesize the evidence available prior to the funding decision. VOI (expected value of perfect and sample information) and PPoR (PATHS model) analyses were undertaken using the developed models. RESULTS AND CONCLUSIONS: VOI and PPoR results agreed in direction, suggesting that the proposed trials would be cost-effective investments. However, results differed in magnitude, largely due to the way each method conceptualizes the possible outcomes of further research and the implementation of research results in practice. Compared with VOI, PPoR is less complex but requires more assumptions. Although the approaches are not free from limitations, they can provide useful input for research funding decisions.


Assuntos
Pesquisa Biomédica/economia , Técnicas de Apoio para a Decisão , Projetos de Pesquisa , Carcinoma Pulmonar de Células não Pequenas , Análise Custo-Benefício , Financiamento Pessoal/economia , Humanos , Masculino , Modelos Teóricos , Neoplasias da Próstata , Anos de Vida Ajustados por Qualidade de Vida
9.
Trials ; 15: 346, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-25187348

RESUMO

BACKGROUND: If multiple Phase II randomized trials exist then meta-analysis is favorable to increase statistical power and summarize the existing evidence about an intervention's effect in order to help inform Phase III decisions. We consider some statistical issues for meta-analysis of Phase II trials for this purpose, as motivated by a real example involving nine Phase II trials of bolus thrombolytic therapy in acute myocardial infarction with binary outcomes. METHODS: We propose that a Bayesian random effects logistic regression model is most suitable as it models the binomial distribution of the data, helps avoid continuity corrections, accounts for between-trial heterogeneity, and incorporates parameter uncertainty when making inferences. The model also allows predictions that inform Phase III decisions, and we show how to derive: (i) the probability that the intervention will be truly beneficial in a new trial, and (ii) the probability that, in a new trial with a given sample size, the 95% credible interval for the odds ratio will be entirely in favor of the intervention. As Phase II trials are potentially optimistic due to bias in design and reporting, we also discuss how skeptical prior distributions can reduce this optimism to make more realistic predictions. RESULTS: In the example, the model identifies heterogeneity in intervention effect missed by an I-squared of 0%. Prediction intervals accounting for this heterogeneity are shown to support subsequent Phase III trials. The probability of success in Phase III trials increases as the sample size increases, up to 0.82 for intracranial hemorrhage and 0.79 for reinfarction outcomes. CONCLUSIONS: The choice of meta-analysis methods can influence the decision about whether a trial should proceed to Phase III and thus need to be clearly documented and investigated whenever a Phase II meta-analysis is performed.


Assuntos
Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Teorema de Bayes , Humanos , Infarto do Miocárdio/tratamento farmacológico , Viés de Publicação , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , Terapia Trombolítica
10.
Int J Cancer ; 133(2): 446-54, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23292999

RESUMO

Smoking is a strong risk factor of bladder cancer (BC), but it is currently unclear whether smoking is also associated with severity of BC at diagnosis. We performed a large hospital-based case-comparison study, examining the relation between smoking and clinical characteristics of BC at diagnosis. A total of 1,544 cases from participating hospitals in the West Midlands were recruited between 19 December 2005 and 21 April 2011. Eligible cases were adult BC patients without a previous history of this disease. At time of diagnosis, semi-structured face-to-face interviews were conducted by trained research nurses to collect smoking information. Clinical characteristics were obtained from medical records. Linear mixed models were performed to calculate predicted means in clinical outcomes for a variety of smoking behaviors. A p < 0.05 was considered statistically significant. After adjustment for age and gender, current smokers were on average 4.0 years younger at diagnosis (95% CI: -5.9 to -2.0), had larger tumors (mean difference: 0.48 cm, 95% CI: 0.04-0.91), a higher T stage (mean difference: 0.25, 95% CI: 0.08-0.41), and a borderline significantly higher grade than never smokers (mean difference: 0.15, 95% CI: 0.00-0.30). Our results suggest that smoking could be associated with a more malignant phenotype of BC at diagnosis. More research is needed on the relation between smoking and prognosis, but our results could strengthen the message about the potential risks of smoking to these patients.


Assuntos
Fumar/efeitos adversos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Idade de Início , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Fenótipo , Prognóstico , Fatores de Risco , Reino Unido/epidemiologia , Neoplasias da Bexiga Urinária/epidemiologia
11.
Stat Appl Genet Mol Biol ; 11(3): Article 2, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22499705

RESUMO

In cancer clinical proteomics, MALDI and SELDI profiling are used to search for biomarkers of potentially curable early-stage disease. A given number of samples must be analysed in order to detect clinically relevant differences between cancers and controls, with adequate statistical power. From clinical proteomic profiling studies, expression data for each peak (protein or peptide) from two or more clinically defined groups of subjects are typically available. Typically, both exposure and confounder information on each subject are also available, and usually the samples are not from randomized subjects. Moreover, the data is usually available in replicate. At the design stage, however, covariates are not typically available and are often ignored in sample size calculations. This leads to the use of insufficient numbers of samples and reduced power when there are imbalances in the numbers of subjects between different phenotypic groups. A method is proposed for accommodating information on covariates, data imbalances and design-characteristics, such as the technical replication and the observational nature of these studies, in sample size calculations. It assumes knowledge of a joint distribution for the protein expression values and the covariates. When discretized covariates are considered, the effect of the covariates enters the calculations as a function of the proportions of subjects with specific attributes. This makes it relatively straightforward (even when pilot data on subject covariates is unavailable) to specify and to adjust for the effect of the expected heterogeneities. The new method suggests certain experimental designs which lead to the use of a smaller number of samples when planning a study. Analysis of data from the proteomic profiling of colorectal cancer reveals that fewer samples are needed when a study is balanced than when it is unbalanced, and when the IMAC30 chip-type is used. The method is implemented in the clippda package and is available in R at: http://www.bioconductor.org/help/bioc-views/release/bioc/html/clippda.html.


Assuntos
Espectrometria de Massas , Proteínas/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Algoritmos , Simulação por Computador , Humanos , Modelos Estatísticos , Projetos de Pesquisa , Tamanho da Amostra
12.
PLoS One ; 6(10): e25164, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22022380

RESUMO

PURPOSE: Despite discrepant results on clinical utility, several trials are already prospectively randomizing non-small cell lung cancer (NSCLC) patients by ERCC1 status. We aimed to characterize the prognostic and predictive effect of ERCC1 by systematic review and meta-analysis. METHODS: Eligible studies assessed survival and/or chemotherapy response in NSCLC or SCLC by ERCC1 status. Effect measures of interest were hazard ratio (HR) for survival or relative risk (RR) for chemotherapy response. Random-effects meta-analyses were used to account for between-study heterogeneity, with unadjusted/adjusted effect estimates considered separately. RESULTS: 23 eligible studies provided survival results in 2,726 patients. Substantial heterogeneity was observed in all meta-analyses (I(2) always >30%), partly due to variability in thresholds defining 'low' and 'high' ERCC1. Meta-analysis of unadjusted estimates showed high ERCC1 was associated with significantly worse overall survival in platinum-treated NSCLC (average unadjusted HR = 1.61, 95%CI:1.23-2.1, p = 0.014), but not in NSCLC untreated with chemotherapy (average unadjusted HR = 0.82, 95%CI:0.51-1.31). Meta-analysis of adjusted estimates was limited by variable choice of adjustment factors and potential publication bias (Egger's p<0.0001). There was evidence that high ERCC1 was associated with reduced response to platinum (average RR = 0.80; 95%CI:0.64-0.99). SCLC data were inadequate to draw firm conclusions. CONCLUSIONS: Current evidence suggests high ERCC1 may adversely influence survival and response in platinum-treated NSCLC patients, but not in non-platinum treated, although definitive evidence of a predictive influence is lacking. International consensus is urgently required to provide consistent, validated ERCC1 assessment methodology. ERCC1 assessment for treatment selection should currently be restricted to, and evaluated within, clinical trials.


Assuntos
Proteínas de Ligação a DNA/genética , Endonucleases/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Publicações , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Diretrizes para o Planejamento em Saúde , Humanos , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento
13.
Proteomics Clin Appl ; 5(9-10): 493-503, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21805675

RESUMO

PURPOSE: There is a need for better biomarkers to both detect bladder cancer and distinguish muscle-invasive (stage T2+) from non-invasive (stage Ta/T1) disease. We assess whether MALDI-TOF-MS of the urine peptidome can achieve this. EXPERIMENTAL DESIGN: We analysed urine from 751 patients with bladder cancer and 127 patients without bladder cancer. Endogenous peptide profiling was performed using a Bruker Ultraflextreme MALDI-TOF-MS. RESULTS: Significant differences were seen between the spectra of urine from patients with and without T2+ disease. Albumin, total protein and haematuria were also elevated in T2+ patients. Haematuria was detected in 39% of patients with Ta/T1 disease and in 77% of patients with T2+ disease. Class prediction models based on MALDI data produced areas under receiver-operator characteristic curves of up to 0.76 but did not significantly outperform a model based on total protein alone. Many peptides significantly associated with invasive disease are fragments of abundant blood proteins and are also associated with haematuria. CONCLUSIONS AND CLINICAL RELEVANCE: Microscopic haematuria is strongly associated with invasive disease; even traces of blood/plasma strongly influence the urinary peptidome. This needs to be taken into consideration when using 'omic' methods to search for urinary biomarkers as blood proteins may give false-positive results.


Assuntos
Peptídeos/urina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Neoplasias da Bexiga Urinária/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biomarcadores Tumorais/urina , Feminino , Hematúria/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Curva ROC , Neoplasias da Bexiga Urinária/patologia
14.
J Clin Oncol ; 29(12): 1531-8, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21422407

RESUMO

PURPOSE: The Tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial included a prospectively planned pathology substudy testing the predictive value of progesterone receptor (PgR) expression for outcome of estrogen receptor-positive (ER-positive) early breast cancer treated with exemestane versus tamoxifen. PATIENTS AND METHODS: Pathology blocks from 4,781 TEAM patients randomly assigned to exemestane versus tamoxifen followed by exemestane for 5 years of total therapy were collected centrally, and tissue microarrays were constructed from samples from 4,598 patients. Quantitative analysis of hormone receptors (ER and PgR) was performed by using image analysis and immunohistochemistry, and the results were linked to outcome data from the main TEAM trial and analyzed relative to disease-free survival and treatment. RESULTS: Of 4,325 eligible ER-positive patients, 23% were PgR-poor (Allred < 4) and 77% were PgR- rich (Allred ≥ 5). No treatment-by-marker effect for PgR was observed for exemestane versus tamoxifen (PgR-rich hazard ratio [HR], 0.83; 95% CI, 0.65 to 1.05; PgR-poor HR, 0.85; 95% CI, 0.61 to 1.19; P = .88 for interaction). Both PgR and ER expression were associated with patient prognosis in univariate (PgR HR, 0.53; 95% CI, 0.43 to 0.65; P < .001; ER HR, 0.66; 95% CI, 0.51 to 0.86; P = .002), and multivariate analyses (P < .001 and P = .001, respectively). A trend toward a treatment-by-marker effect for ER-rich patients was observed. CONCLUSION: Preferential exemestane versus tamoxifen treatment benefit was not predicted by PgR expression; conversely, patients with ER-rich tumors may derive additional benefit from exemestane. Quantitative analysis of ER and PgR expression provides highly significant information on risk of early relapse (within 1 to 3 years) during treatment.


Assuntos
Androstadienos/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Seleção de Pacientes , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tamoxifeno/uso terapêutico , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Europa (Continente) , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Análise Serial de Tecidos , Resultado do Tratamento
15.
Lancet ; 373(9663): 567-74, 2009 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-19217991

RESUMO

BACKGROUND: The role and dose of anticoagulants in thromboprophylaxis for patients with cancer receiving chemotherapy through central venous catheters (CVCs) is controversial. We therefore assessed whether warfarin reduces catheter-related thrombosis compared with no warfarin and whether the dose of warfarin determines the thromboprophylactic effect. METHODS: In 68 clinical centres in the UK, we randomly assigned 1590 patients aged at least 16 years with cancer who were receiving chemotherapy through CVCs to no warfarin, fixed-dose warfarin 1 mg per day, or dose-adjusted warfarin per day to maintain an international normalised ratio between 1.5 and 2.0. Clinicians who were certain of the benefit of warfarin randomly assigned patients to fixed-dose or dose-adjusted warfarin groups. The primary outcome was the rate of radiologically proven, symptomatic catheter-related thrombosis. Analysis was by intention to treat. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN 50312145. FINDINGS: Compared with no warfarin (n=404), warfarin (n=408; 324 [79%] on fixed-dose and 84 [21%] on dose-adjusted) did not reduce the rate of catheter-related thromboses (24 [6%] vs 24 [6%]; relative risk 0.99, 95% CI 0.57-1.72, p=0.98). However, compared with fixed-dose warfarin (n=471), dose-adjusted warfarin (n=473) was superior in the prevention of catheter-related thromboses (13 [3%] vs 34 [7%]; 0.38, 0.20-0.71, p=0.002). Major bleeding events were rare; an excess was noted with warfarin compared with no warfarin (7 vs 1, p=0.07) and with dose-adjusted warfarin compared with fixed-dose warfarin (16 vs 7, p=0.09). A combined endpoint of thromboses and major bleeding showed no difference between comparisons. We did not note a survival benefit in either comparison. INTERPRETATION: The findings show that prophylactic warfarin compared with no warfarin is not associated with a reduction in symptomatic catheter-related or other thromboses in patients with cancer and therefore we should consider newer treatments. FUNDING: Medical Research Council and Cancer Research UK.


Assuntos
Anticoagulantes/uso terapêutico , Antineoplásicos/administração & dosagem , Cateterismo Venoso Central/efeitos adversos , Neoplasias/tratamento farmacológico , Trombose Venosa/etiologia , Trombose Venosa/prevenção & controle , Varfarina/uso terapêutico , Idoso , Anticoagulantes/efeitos adversos , Antineoplásicos/uso terapêutico , Feminino , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Neoplasias/mortalidade , Varfarina/efeitos adversos
17.
Proteomics ; 9(1): 74-86, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19053145

RESUMO

Mass spectrometric profiling approaches such as MALDI-TOF and SELDI-TOF are increasingly being used in disease marker discovery, particularly in the lower molecular weight proteome. However, little consideration has been given to the issue of sample size in experimental design. The aim of this study was to develop a protocol for the use of sample size calculations in proteomic profiling studies using MS. These sample size calculations can be based on a simple linear mixed model which allows the inclusion of estimates of biological and technical variation inherent in the experiment. The use of a pilot experiment to estimate these components of variance is investigated and is shown to work well when compared with larger studies. Examination of data from a number of studies using different sample types and different chromatographic surfaces shows the need for sample- and preparation-specific sample size calculations.


Assuntos
Análise Serial de Proteínas/métodos , Proteoma/análise , Projetos de Pesquisa , Análise de Variância , Proteínas Sanguíneas/análise , Humanos , Espectrometria de Massas , Plasma/química , Tamanho da Amostra
18.
Health Econ ; 17(1): 67-81, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17533622

RESUMO

There is an increasing need to establish whether health-care interventions are cost effective as well as clinically effective. It is becoming increasingly common for cost studies to be incorporated into clinical trials, either on all patients or more usually on a subset of patients. Establishing the total cost per patient is complex, as it requires information on resource use, which may come from a variety of different sources. This complexity may lead to considerable missing data, and can result in some patients only having partial cost information. In this paper we consider a clinical trial consisting of 351 patients with advanced non-small cell lung cancer comparing chemotherapy with standard palliative care. A subset of 115 patients was selected for the cost sub-study. Total cost was split into four components, for which resource use was collected. Complete resource data were available on 82 patients. For the remaining patients at least one of the cost components was missing. The objective of this paper is to develop a Bayesian approach which simultaneously models both the clinical effectiveness data and the cost data, by modelling the individual components. This also provides estimates of the cost-effectiveness in terms of the Incremental Net Monetary Benefit (INMB) and Cost-Effectiveness Acceptability Curves (CEAC). We compare a number of different models of increasing complexity. The models estimate the interrelationships between the four cost components and survival, and thus enable a predictive distribution for each missing cost item to be obtained.


Assuntos
Antineoplásicos/economia , Ensaios Clínicos como Assunto/estatística & dados numéricos , Modelos Econométricos , Cuidados Paliativos/economia , Antineoplásicos/uso terapêutico , Teorema de Bayes , Carcinoma Pulmonar de Células não Pequenas/economia , Carcinoma Pulmonar de Células não Pequenas/terapia , Análise Custo-Benefício , Humanos , Neoplasias Pulmonares/economia , Neoplasias Pulmonares/terapia
19.
BJU Int ; 101(6): 702-5; discussion 705-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18005206

RESUMO

OBJECTIVE: To investigate whether narrow-band imaging (NBI) flexible cystoscopy improves the detection rate of urothelial carcinomas (UCs) of the bladder. NBI is an optical image enhancement technology in which the narrow bandwidth of light is strongly absorbed by haemoglobin and penetrates only the surface of tissue, increasing the visibility of capillaries and other delicate tissue surface structures by enhancing contrast between the two. PATIENTS AND METHODS: Between November 2005 and May 2007 at the Queen Elizabeth Hospital, Birmingham, NBI flexible cystoscopy was performed on 29 patients with known recurrences of UC of the bladder after initial conventional white-light imaging (WLI) flexible cystoscopy with the same instrument (Olympus Lucera sequential RGB endoscopy system). RESULTS: Subjectively, NBI provided a much clearer view of bladder UCs and in particular their delicate capillary architecture. Objectively, NBI detected 15 additional UCs in 12 of 29 patients (41%), as compared with WLI. The mean (sd) difference was 0.52 (0.74) UCs per patient (P < 0.001, Wilcoxon signed-rank test). CONCLUSIONS: Even in the few patients studied there is strong evidence that NBI differs from WLI in the number of UCs it detects, with a significantly increased detection rate. We feel that further evaluation of NBI flexible cystoscopy in more patients will show this technique to be highly valuable in the detection of both new and recurrent bladder UCs, and this work is continuing in our unit.


Assuntos
Cistoscopia/métodos , Aumento da Imagem , Recidiva Local de Neoplasia/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Bexiga Urinária/patologia , Humanos , Estudos Prospectivos
20.
J Clin Oncol ; 25(30): 4821-8, 2007 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-17947731

RESUMO

PURPOSE: The SIGNIFICANT (Simple Investigation in Neutropenic Individuals of the Frequency of Infection after Chemotherapy +/- Antibiotic in a Number of Tumours) trial reported a reduction in febrile episodes (FEs) among 1,565 patients with solid cancers and lymphomas receiving cyclical, myelosuppressive chemotherapy (causing grade 4 neutropenia) in a randomized, placebo-controlled, double-blind trial of levofloxacin (P = .01). In response to concerns that increased antibacterial prescribing selects for microbial resistance, we examined our data to explore the rationale for more limited prophylaxis. PATIENTS AND METHODS: The risk of FE was calculated for control patients on first versus nonfirst cycles, with or without first-cycle FE, and within subgroups defined by cancer type, performance status (PS), age, and treatment context (adjuvant v nonadjuvant). Using the randomized trial data, the prophylactic efficacy of levofloxacin was examined for the same subgroups. RESULTS: The per-cycle FE incidence was much lower on nonfirst (3.3%) versus first cycles (8.0%). Prophylaxis was less effective for nonfirst (odds ratio [OR] = 0.78; P = .16) compared with first cycles (OR = 0.42; P < .001). However, FE on cycle 1 predicted a much higher risk of FE and a trend to continued prophylactic efficacy on subsequent cycles. FE rate was greatest for testicular cancer (27.9%), then small-cell lung cancer (17.3%), and lowest for breast cancer (11.5%). Prophylactic efficacy was consistent across age, sex, PS, treatment context, and disease type (except possibly non-Hodgkin's lymphoma). CONCLUSION: Under pressure to limit antibacterial use, these exploratory data support offering prophylactic levofloxacin on cycle 1 only of myelosuppressive cancer chemotherapy and on subsequent cycles after a cycle-1 fever. Prophylactic levofloxacin is effective regardless of age, PS, or tumor type.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Antineoplásicos/efeitos adversos , Infecções Bacterianas/prevenção & controle , Levofloxacino , Neoplasias/tratamento farmacológico , Ofloxacino/uso terapêutico , Seleção de Pacientes , Adulto , Infecções Bacterianas/etiologia , Método Duplo-Cego , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Placebos , Fatores de Risco
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