324 research outputs found

    Informative noncompliance in endpoint trials

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    Noncompliance with study medications is an important issue in the design of endpoint clinical trials. Including noncompliant patient data in an intention-to-treat analysis could seriously decrease study power. Standard methods for calculating sample size account for noncompliance, but all assume that noncompliance is noninformative, i.e., that the risk of discontinuation is independent of the risk of experiencing a study endpoint. Using data from several published clinical trials (OPTIMAAL, LIFE, RENAAL, SOLVD-Prevention and SOLVD-Treatment), we demonstrate that this assumption is often untrue, and we discuss the effect of informative noncompliance on power and sample size

    Oxygen therapy: time to move on?

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    This analysis examines the roots of clinical practice regarding oxygen therapy and finds that some aspects have changed very little over the past 200 years. Oxygen is commonly prescribed and administered as a therapy across all healthcare settings, particularly for the treatment and management of respiratory conditions, both acute and chronic. Yet despite its widespread use and recent advances in understanding and guidance, poor practice and controversies regarding its use persist. This historical analysis highlights origins in practice that may suggest where the roots of these fallacies lie, highlighting potential ambiguities and myths that have permeated clinical and social contexts. It can be considered that based on clinical presumptions and speculation the prolific and injudicious use of oxygen was encouraged and the legacy for today’s practice seeded. The conjectures proposed here may enable modern day erroneous beliefs to be confronted and clinical practice to move on

    The use of preoperative radiotherapy in the management of patients with clinically resectable rectal cancer: a practice guideline

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    BACKGROUND: This systematic review with meta-analysis was designed to evaluate the literature and to develop recommendations regarding the use of preoperative radiotherapy in the management of patients with resectable rectal cancer. METHODS: The MEDLINE, CANCERLIT and Cochrane Library databases, and abstracts published in the annual proceedings of the American Society of Clinical Oncology and the American Society for Therapeutic Radiology and Oncology were systematically searched for evidence. Relevant reports were reviewed by four members of the Gastrointestinal Cancer Disease Site Group and the references from these reports were searched for additional trials. External review by Ontario practitioners was obtained through a mailed survey. Final approval of the practice guideline report was obtained from the Practice Guidelines Coordinating Committee. RESULTS: Two meta-analyses of preoperative radiotherapy versus surgery alone, nineteen trials that compared preoperative radiotherapy plus surgery to surgery alone, and five trials that compared preoperative radiotherapy to alternative treatments were obtained. Randomized trials demonstrate that preoperative radiotherapy followed by surgery is significantly more effective than surgery alone in preventing local recurrence in patients with resectable rectal cancer and it may also improve survival. A single trial, using surgery with total mesorectal excision, has shown similar benefits in local recurrence. CONCLUSION: For adult patients with clinically resectable rectal cancer we conclude that: • Preoperative radiotherapy is an acceptable alternative to the previous practice of postoperative radiotherapy for patients with stage II and III resectable rectal cancer; • Both preoperative and postoperative radiotherapy decrease local recurrence but neither improves survival as much as postoperative radiotherapy combined with chemotherapy. Therefore, if preoperative radiotherapy is used, chemotherapy should be added postoperatively to at least patients with stage III disease

    Childhood leukaemia: long-term excess mortality and the proportion ‘cured'

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    Survival from childhood leukaemia has increased, but the proportion of children cured is unknown. The proportion ‘cured' is defined as the proportion of survivors for whom, as a group, there is no longer excess mortality compared to the general population. Average time to cure is defined as the time since diagnosis at which the excess mortality rate has declined to or below a predetermined small value. Data on children diagnosed with leukaemia during 1971–2000 in Great Britain were used to estimate trends in survival, the proportion cured and the average time to cure. Five-year survival for all types of leukaemia combined rose from 33 to 79% by 2000. The percentage cured rose from 25 to 68% by 1995; it is predicted to increase to 73% for those diagnosed more recently. Average time to cure increased from 12 years (95% confidence interval (CI): 11–14) to 19 years (95% CI: 14–26) for lymphoid leukaemia (average annual increase of 0.3 years; P<0.001), but remained at about 5 years for acute nonlymphoblastic leukaemia. The proportion of children cured of leukaemia has risen dramatically, but the period of excess mortality associated with lymphoid leukaemia has also increased, possibly because of late relapse, secondary malignancy and toxicity from treatment

    Limited Relationship between Cervico-Vaginal Fluid Cytokine Profiles and Cervical Shortening in Women at High Risk of Spontaneous Preterm Birth

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    Objective: to determine the relationship between high vaginal pro-inflammatory cytokines and cervical shortening in women at high risk of spontaneous preterm labor and to assess the influence of cervical cerclage and vaginal progesterone on this relationship. Methods: this prospective longitudinal observational study assessed 112 women with at least one previous preterm delivery between 16 and 34 weeks’ gestation. Transvaginal cervical length was measured and cervico-vaginal fluid sampled every two weeks until 28 weeks. If the cervix shortened (<25 mm) before 24 weeks’ gestation, women (cases) were randomly assigned to cerclage or progesterone and sampled weekly. Cytokine concentrations were measured in a subset of cervico-vaginal fluid samples (n = 477 from 78 women) by 11-plex fluid-phase immunoassay. Results: all 11 inflammatory cytokines investigated were detected in cervico-vaginal fluid from women at high risk of preterm birth, irrespective of later cervical shortening. At less than 24 weeks’ gestation and prior to intervention, women destined to develop a short cervix (n = 36) exhibited higher cervico-vaginal concentrations than controls (n = 42) of granulocyte-macrophage colony-stimulating factor [(GM-CSF) 16.2 fold increase, confidence interval (CI) 1.8–147; p = 0.01] and monocyte chemotactic protein-1 [(MCP-1) 4.8, CI 1.0–23.0; p = 0.05]. Other cytokines were similar between cases and controls. Progesterone treatment did not suppress cytokine concentrations. Interleukin (IL)-6, IL-8, granulocyte colony-stimulating factor (G-CSF), interferon (IFN)-γ and tumour necrosis factor (TNF)-α concentrations were higher following randomization to cerclage versus progesterone (p<0.05). Cerclage, but not progesterone treatment, was followed by a significant increase in cervical length [mean 11.4 mm, CI 5.0–17.7; p<0.001]. Conclusions: although GM-CSF and MCP-1 cervico-vaginal fluid concentrations were raised, the majority of cervico-vaginal cytokines did not increase in association with cervical shortening. Progesterone treatment showed no significant anti-inflammation action on cytokine concentrations. Cerclage insertion was associated with an increase in the majority of inflammatory markers and cervical length

    Management of acute promyelocytic leukemia: Recommendations from an expert panel on behalf of the European LeukemiaNet

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    The introduction of all-trans retinoic acid (ATRA) and, more recently, arsenic trioxide (ATO) into the therapy of acute promyelocytic leukemia (APL) has revolutionized the management and outcome of this disease. Several treatment strategies using these agents, usually in combination with chemotherapy, but also without or with minimal use of cytotoxic agents, have provided excellent therapeutic results. Cure of APL patients, however, is also dependent on peculiar aspects related to the management and supportive measures that are crucial to counteract life-threatening complications associated with the disease biology and molecularly targeted treatment. The European LeukemiaNet recently appointed an international panel of experts to develop evidence- and expert opinion-based guidelines on the diagnosis and management of APL. Together with providing current indications on genetic diagnosis, modern risk-adapted front-line therapy and salvage treatment, the review contains specific recommendations for the ide

    The proteomic response in glioblastoma in young patients

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    Increasing age is an important prognostic variable in glioblastoma (GBM). We have defined the proteomic response in GBM samples from 7 young patients (mean age 36 years) compared to peritumoural-control samples from 10 young patients (mean age 32 years). 2-Dimensional-gel-electrophoresis, image analysis, and protein identification (LC/MS) were performed. 68 proteins were significantly altered in young GBM samples with 29 proteins upregulated and 39 proteins downregulated. Over 50 proteins are described as altered in GBM for the first time. In a parallel analysis in old GBM (mean age 67 years), an excellent correlation could be demonstrated between the proteomic profile in young GBM and that in old GBM patients (r(2) = 0.95) with only 5 proteins altered significantly (p < 0.01). The proteomic response in young GBM patients highlighted alterations in protein–protein interactions in the immunoproteosome, NFkB signalling, and mitochondrial function and the same systems participated in the responses in old GBM patients. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11060-014-1474-6) contains supplementary material, which is available to authorized users
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