232 resultados para Patient selection
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IMPORTANCE: The discontinuation of randomized clinical trials (RCTs) raises ethical concerns and often wastes scarce research resources. The epidemiology of discontinued RCTs, however, remains unclear. OBJECTIVES: To determine the prevalence, characteristics, and publication history of discontinued RCTs and to investigate factors associated with RCT discontinuation due to poor recruitment and with nonpublication. DESIGN AND SETTING: Retrospective cohort of RCTs based on archived protocols approved by 6 research ethics committees in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics and planned recruitment from included protocols. Last follow-up of RCTs was April 27, 2013. MAIN OUTCOMES AND MEASURES: Completion status, reported reasons for discontinuation, and publication status of RCTs as determined by correspondence with the research ethics committees, literature searches, and investigator surveys. RESULTS: After a median follow-up of 11.6 years (range, 8.8-12.6 years), 253 of 1017 included RCTs were discontinued (24.9% [95% CI, 22.3%-27.6%]). Only 96 of 253 discontinuations (37.9% [95% CI, 32.0%-44.3%]) were reported to ethics committees. The most frequent reason for discontinuation was poor recruitment (101/1017; 9.9% [95% CI, 8.2%-12.0%]). In multivariable analysis, industry sponsorship vs investigator sponsorship (8.4% vs 26.5%; odds ratio [OR], 0.25 [95% CI, 0.15-0.43]; P < .001) and a larger planned sample size in increments of 100 (-0.7%; OR, 0.96 [95% CI, 0.92-1.00]; P = .04) were associated with lower rates of discontinuation due to poor recruitment. Discontinued trials were more likely to remain unpublished than completed trials (55.1% vs 33.6%; OR, 3.19 [95% CI, 2.29-4.43]; P < .001). CONCLUSIONS AND RELEVANCE: In this sample of trials based on RCT protocols from 6 research ethics committees, discontinuation was common, with poor recruitment being the most frequently reported reason. Greater efforts are needed to ensure the reporting of trial discontinuation to research ethics committees and the publication of results of discontinued trials.
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The aim of this study was to determine the influence of comorbidity on outcome after pulmonary resection in patients over 75 years old. Three hundred and thirty-three patients with non-small-cell lung cancer operated on between 1998 and 2002 were divided into 3 age groups: < 60 years (group 1), 60-75 years (group 2), > 75 years (group 3). Overall operative mortality was 0.3%; 30-day mortality was 1%. There were more major complications with re-operation in groups 1 and 2, but minor complications occurred significantly more frequently in group 3 (36% vs 16%). Overall mean hospital stay was 12 days, with no significant difference among groups. Three-year survival rates were: 80%, 70%, and 65% in groups 1, 2, and 3, respectively, with no significant difference among groups. Age or the presence of comorbidity should not be considered contraindications for lung resection. With proper patient selection and careful preoperative evaluation, many major complications after pneumonectomy are avoidable.
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The authors observed a high rate of suicide (6/140 patients, 4.3%) in a large cohort of patients with movement disorders treated with deep brain stimulation (DBS). Apparent risk factors included a previous history of severe depression and multiple successive DBS surgeries, whereas there was no relationship with the underlying condition, DBS target, electrical parameters, or modifications of treatment. Paradoxically, all patients experienced an excellent motor outcome following the procedure. The authors propose that patients at high risk for suicide should be excluded from DBS surgery.
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Spinal cord stimulation (SCS) represents a well established procedure in the treatment of critical ischemia of the extremities. The knowledge and distribution of SCS in Austria are still poor despite satisfactory data. The evaluations and recommendations from the consensus group demonstrate that SCS might represent a suitable additional treatment option for selected patients with peripheral arterial disease (PAD) when performed in experienced centers under clear indications. The complication rate is low and mainly due to device-related problems. There are valid scientific criteria proving that SCS treatment can reduce the risk of amputation, decrease pain and improve wound healing in patients with non-reconstructable, non-unstable PAD in stages IV and V according to Rutherford (stages III and IV according to Fontaine).This effect is more evident when patient selection is based on tcPO(2) measurements. A careful selection of patients is essential for the success of this neuromodulatory treatment, in addition a certain degree of patient compliance in terms of perception and understanding of the therapy is mandatory.
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In 1875, 7 years prior to the description of the Koch bacillus, Klebs visualized the first Streptococcus pneumoniae in a pleural fluid. Since then, this organism has played a determinant role in biomedical science. From a biological point of view, it was largely implicated in the development of passive and active immunization by serotherapy and vaccination, respectively. Genetic transformation was also first observed in S. pneumoniae, leading to the discovery of DNA. From a clinical point of view, S. pneumoniae is still today a prime cause of otitis media in children and of pneumonia in all age groups, as well as a predominant cause of meningitis and bacteremia. In adults, bacteremia is still entailed with a mortality of over 25%. Although S. pneumoniae remained very sensitive to penicillin for many years, penicillin-resistance has emerged and increased dramatically over the last 15 years. During this period of time, the frequency of penicillin-resistant isolates has increased from < or = 1% to frequencies varying from 20 to 60% in geographic areas as diverse as South Africa, Spain, France, Hungary, Iceland, Alaska, and numerous regions of the United States and South America. In Switzerland, the current frequency of penicillin-resistant pneumococci ranges between 5 and > or = 10%. The increase in penicillin-resistant pneumococci correlates with the intensive use of beta-lactam antibiotics. The mechanism of resistance is not due to bacterial production of penicillinase, but to an alteration of the bacterial target of penicillin, the so-called penicillin-binding proteins. Resistance is subdivided into (i) inter mediate level resistance (minimal inhibitory concentration [MIC] of penicillin of 0.1-1 mg/L) and (ii) high level resistance (MCI > or = 2 mg/L). The clinical significance of intermediate resistance remains poorly defined. On the other hand, highly resistant strains were responsible for numerous therapeutical failures, especially in cases of meningitis. Antibiotics recommended against penicillin-resistant pneumococci include cefotaxime, ceftriaxone, imipenem and in some instances vancomycin. However, penicillin-resistant pneumococci tend to present cross-resistances to all the antibotics of the beta-lactam family and could even become resistant to the last resort drugs mentioned above. Thus, in conclusion, the explosion of resistance to penicillin in pneumococci is a ubiquitous phenomenon which must be fought against by (i) a strict utilization of antibiotics, (ii) the practice of microbiological sampling of infected foci before treatment, (iii) the systematic surveillance of resistance profiles of pneumococci against antibiotics and (iv) the adequate vaccination of populations at risk.
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The O(6)-methylguanine-DNA methyltransferase (MGMT) gene is located at chromosome 10q26 and codes for a DNA repair enzyme that--if active--can counteract the effects of alkylating chemotherapy. Malignant gliomas often have the MGMT gene inactivated due to aberrant methylation of its promoter region. The assessment of the MGMT promoter methylation status has become of clinical relevance as a molecular marker associated with response to alkylating chemotherapy and prolonged survival of glioblastoma patients. MGMT promoter methylation testing is also on the merge of being used as a marker for patient selection within clinical trials, e.g., the current CENTRIC trial that is specifically focusing on patients with MGMT promoter-methylated glioblastomas. In anaplastic gliomas, MGMT promoter methylation is a favorable prognostic marker independent of the type of therapy, i.e., radio- or chemotherapy. This occurrence might be associated with the high incidence of other prognostically favorable molecular markers in these tumors, such as IDH1 mutation, 1p/19q deletion or yet to be identified novel aberrations. A variety of different methods are being used to assess MGMT promoter methylation in clinical samples, which may give rise to inter-laboratory variations in test results. Immunohistochemical determination of MGMT protein expression has not proven reliable for diagnostic purposes. This brief review article aims to summarize the main aspects of MGMT promoter methylation testing in contemporary neuro-oncology, in particular its value as a clinically useful molecular marker, putting it into the context of other molecular markers of clinical use in gliomas of adult patients.
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The choice of design between individual randomisation, cluster or pseudo-cluster randomisation is often made difficult. Clear methodological guidelines have been given for trials in general practice, but not for vaccine trials. This article proposes a decisional flow-chart to choose the most adapted design for evaluating the effectiveness of a vaccine in large-scale studies. Six criteria have been identified: importance of herd immunity or herd protection, ability to delimit epidemiological units, homogeneity of transmission probability across sub-populations, population's acceptability of randomisation, availability of logistical resources, and estimated sample size. This easy to use decisional method could help sponsors, trial steering committees and ethical committees adopt the most suitable design.
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PURPOSE: Spine surgery rates are increasing worldwide. Treatment failures are often attributed to poor patient selection and inappropriate treatment, but for many spinal disorders there is little consensus on the precise indications for surgery. With an aging population, more patients with lumbar degenerative spondylolisthesis (LDS) will present for surgery. The aim of this study was to develop criteria for the appropriateness of surgery in symptomatic LDS. METHODS: A systematic review was carried out to summarize the current level of evidence for the treatment of LDS. Clinical scenarios were generated comprising combinations of signs and symptoms in LDS and other relevant variables. Based on the systematic review and their own clinical experience, twelve multidisciplinary international experts rated each scenario on a 9-point scale (1 highly inappropriate, 9 highly appropriate) with respect to performing decompression only, fusion, and instrumented fusion. Surgery for each theoretical scenario was classified as appropriate, inappropriate, or uncertain based on the median ratings and disagreement in the ratings. RESULTS: 744 hypothetical scenarios were generated; overall, surgery (of some type) was rated appropriate in 27 %, uncertain in 41 % and inappropriate in 31 %. Frank panel disagreement was low (7 % scenarios). Face validity was shown by the logical relationship between each variable's subcategories and the appropriateness ratings, e.g., no/mild disability had a mean appropriateness rating of 2.3 ± 1.5, whereas the rating for moderate disability was 5.0 ± 1.6 and for severe disability, 6.6 ± 1.6. Similarly, the average rating for no/minimal neurological abnormality was 2.3 ± 1.5, increasing to 4.3 ± 2.4 for moderate and 5.9 ± 1.7 for severe abnormality. The three variables most likely (p < 0.0001) to be components of scenarios rated "appropriate" were: severe disability, no yellow flags, and severe neurological deficit. CONCLUSION: This is the first study to report criteria for determining candidacy for surgery in LDS developed by a multidisciplinary international panel using a validated method (RAM). The panel ratings followed logical clinical rationale, indicating good face validity. The work refines clinical classification and the phenotype of degenerative spondylolisthesis. The predictive validity of the criteria should be evaluated prospectively to examine whether patients treated "appropriately" have better clinical outcomes.
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The current standard treatment for early stage (I-III) renal cell cancer (RCC) is surgery. While the prognosis of stage I tumors is excellent, stage II and particularly stage III have a high risk of relapse. The adjuvant treatment of patients with RCC remains an area of investigation, with patient selection being a key aspect. There are currently two prognostic nomograms to establish the risk of relapse in patients with resected RCC. The results of earlier studies of adjuvant therapy, including the use chemotherapy and/or immunotherapy after nephrectomy have failed to show any benefit in the outcome of patients at risk of developing local recurrence or distant metastases. Two recent phase III trials with vaccines (autologous tumor cell vaccine and autologous tumor-derived heat shock protein peptide complex-96) have shown promising, albeit still preliminary, results. In the metastatic RCC setting, recent advances in the molecular understanding of oncogenic pathways have led to the development of new therapeutic strategies with the use of targeted therapies in the adjuvant setting. Neoadjuvant treatment is another treatment modality currently being evaluated for patients with early disease and in patients with metastatic RCC with inoperable primary tumors. The questions that remain unanswered include activity of these agents in early stages of the disease, patient selection, optimal start time of the adjuvant treatment, and finally, the optimal length of treatment.
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The development and use of chemotherapy for patients with prostate cancer was slow and modest in comparison with other solid tumor sites. While many cytotoxic agents and multiple drug combinations were tested during the 1980, the first recognized drug for men with metastatic castration-resistant prostate cancer (mCRPC) was mitoxantrone combined with prednisone in 1996. Mitoxantrone showed an improvement in quality of life and pain compared to men treated with prednisone alone. In 2004, two randomized controlled trials found docetaxel superior to mitoxantrone in PSA response and survival. Despite the somewhat higher side effect rate, quality of life and pain were also improved with docetaxel. Unfortunately only about every second man benefits from this treatment and there are no approved criteria to select patients with better chances of response. It takes about 3 months of treatment to identify non-responders and all patients will ultimately progress and most of them will die of prostate cancer. Many men with mCRPC were treated with mitoxantrone after progression on docetaxel without a strong evidence for such a choice. More recently, the benefit of a second-line chemotherapy was addressed within a randomized controlled trial. A new taxane, cabazitaxel, was found superior to mitoxantrone in terms of overall survival despite the previous treatment with docetaxel and therefore recently approved in this indication. The most important challenges and opportunities for future studies will be the combination of chemotherapy with hormonal or non-hormonal targeted agents, the establishment of treatment algorithms to best sequence docetaxel and cabazitaxel and non-cytotoxic agents. Patient selection criteria as well as early biomarkers of response or resistance would also be important for patients and clinicians. Toxicity and quality of life are particular important aspects of drug development in current and future studies which aim to improve treatment options in this frequently elderly patient population.
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Standard surgical aortic valve replacement with a biological prosthesis remains the treatment of choice for low- and mid-risk elderly patients (traditionally >65 years of age) suffering from severe symptomatic aortic valve stenosis or insufficiency, and for young patients with formal contraindications to long-lasting anticoagulation. Unfortunately, despite the fact that several technical improvements have noticeably improved the resistance of pericardial and bovine bioprostheses to leaflet calcifications and ruptures, the risk of early valve failure with rapid degeneration still exists, especially for patients under haemodialysis and for patients <60 years of age at the time of surgery. Until now, redo open heart surgery under cardiopulmonary bypass and on cardioplegic arrest was the only available therapeutic option in case of bioprosthesis degeneration, but it carried a higher surgical risk when elderly patients with severe concomitant comorbidities were concerned. Since a few years, the advent of new transcatheter aortic valve procedures has opened new horizons in cardiac surgery and, in particular, the possibility of implanting stented valves within the degenerated stented bioprosthesis, the so-called 'valve-in-valve' (VinV) concept, has become a clinical practice in experienced cardiac centres. The VinV procedure represents a minimally invasive approach dedicated to high-risk redo patients, and published preliminary reports have shown a success rate of 100% with absence of significant valvular leaks, acceptable transvalvular gradients and low complication rate. However, this procedure is not riskless and the most important concerns are about the size mismatch and the right positioning within the degenerated bioprosthesis. In this article, we review the limited available literature about VinV procedures, underline important technical details for the positioning and provide guidelines to prevent valve-prosthesis mismatch comparing the three sizes of the only commercially available transapical device, the Edwards Sapien, with the inner diameter of three of the most commonly used stented bioprostheses.