Омела белая Viscum album Mistletoe
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- Survival of cancer patients treated with mistletoe extract (Iscador): a systematic literature review
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- Background
ОграниченияОграничением данного Мета-анализа является то, что суммарные оценки приводятся в действие довольно разнородных данных, хотя наша оценка I2 = 38,3% и положил ниже критической границы 0,5 рекомендованных Хиггинс & Thompson [44]). Тем не менее, как уже было сказано, это должно быть принято во внимание, что в своем исследовании бассейн является составной совершенно различных исследований. Как выживание в долгосрочной перспективе, по определению, могут быть получены только от исследований, которые проводились несколько лет назад, мы также включены старые исследования с использованием методов лечения, которые в настоящее время считаются устаревшими. Стратифицированный анализ, однако, показывает, что Год начала исследования не влияет на совокупный эффект оценки. Этот Мета-анализ был ограничен в опубликованных исследованиях. Хотя, мы старались быть как можно более полные наш поиск исследований, воронки сюжета довольно skewy и указывает на значительную долю систематической ошибки, которая ограничивает доказательств, обнаруженных в этот Мета-анализ. В частности, совокупный эффект оценки являются в основном типа исследования (т.е., подобранная пара дизайн). Это явление уже было признано в других областях исследований, и таким образом не из-за специфического вида вмешательства, представленные здесь [45]. Более того, с этим не спорит против возможности, что у пациентов, получавших Iscador лучше выживаемости, но должны быть показателем спросить можно confounder или модератор переменные, которые еще предстоит идентифицировать. ВыводыВ заключение, общий анализ клинических исследований свидетельствует о том, что адъювантного лечения онкологических больных с Iscador это связано с сокращением смертности. Имея в виду ограничения найти здесь, будущих исследований по оценке воздействия Iscador следует продолжать рассматривать этот вопрос, с особым акцентом на прозрачный дизайн и описание конечных точек, чтобы обеспечить более глубокое понимание лечение часто амортизируются как неэффективные. Информация и соображения, из этого анализа следует относиться серьезно, не только для лучшего изучения качества, но и для обеспечения наилучшего обслуживания больных раком. АббревиатурыCAM: дополнительной или альтернативной медицины; HR: отношение рисков; РКИ: рандомизированных клинических испытаний; SMD: стандартизированные имею в виду различия; VA-E: Viscum album экстракты. BMC Cancer. 2009; 9: 451. Published online Dec 18, 2009. doi: 10.1186/1471-2407-9-451 PMCID: PMC2804713 Survival of cancer patients treated with mistletoe extract (Iscador): a systematic literature reviewThomas Ostermann,#1 Christa Raak,1 and Arndt Büssing  #1
Author information ► Article notes ► Copyright and License information ► This article has been cited by other articles in PMC. Go to: AbstractBackgroundIn Europe, extracts from Viscum album (VA-E), the European white-berry mistletoe, are widely used to treat patients with cancer. MethodsWe searched several databases such as Cochrane, EMBASE, NCCAM, NLM, DIMDI, CAMbase, and Medline. Inclusion criteria were controlled clinical studies on parameters associated with survival in cancer patients treated with Iscador. Outcome data were extracted as they were given in the publication, and expressed as hazard ratios (HR), their logarithm, and the respective standard errors using standard formulas. ResultsWe found 49 publications on the clinical effects of Iscador usage on survival of cancer patients which met our criteria. Among them, 41 studies and strata provided enough data to extract hazard ratios (HR) and their standard errors (Iscador versus no extra treatment). The majority of studies reported positive effects in favour of the Iscador application. Heterogeneity of study results was moderate (I2 = 38.3%, p < 0.0001). The funnel plots were considerably skewed, indicating a publication bias, a notion which is corroborated by statistical means (AC = -1.3, CI: -1.9 to -0.6, p <= 0.0001). A random effect meta-analysis estimated the overall hazard ratio at HR = 0.59 (CI: 0.53 to 0.66, p < 0.0001). Randomized studies showed less effects than non-randomized studies (ratio of HRs: 1.24, CI: 0.79 to 1.92, p = 0.35), and matched-pair studies gave significantly better results than others (ratio of HRs: 0.33; CI: 0.17 to 0.65, p = 0.0012). ConclusionsPooled analysis of clinical studies suggests that adjuvant treatment of cancer patients with the mistletoe extract Iscador is associated with a better survival. Despite obvious limitations, and strong hints for a publication bias which limits the evidence found in this meta-analysis, one can not ignore the fact that studies with positive effects of VA-E on survival of cancer patients are accumulating. Future studies evaluating the effects of Iscador should focus on a transparent design and description of endpoints in order to provide greater insight into a treatment often being depreciated as ineffective, but highly valued by cancer patients. BackgroundComplementary and alternative medicine (CAM) has become increasingly popular over the last decades. According to Bausell et al. [1], especially patients with chronic diseases increasingly seek for CAM-therapies. With a growing amount of health information in the internet, physicians and therapists and patients are often not prepared to judge provided information of CAM-health care approaches properly. Information dissemination of published evidence about the effectiveness of remedies and therapies therefore forms a necessary basis for shared-decision making for patients and practitioners. In Europe, extracts from Viscum album (VA-E), the European white-berry mistletoe, are widely used to treat patients with cancer, but also with arthrosis, hypertension, arteriosclerosis, diabetes etc. [2]. Historically, the intentions of mistletoe uses were manifold and conflicting in several cases (i.e., swellings or tumours, epilepsy, diseases of spleen and liver, labour-pains, 'weakness of the heart' and oedema, eczema, ulcers of the feet, burns, and granulating wounds) [3]. In 1920, mistletoe extracts were introduced for the first time as a cancer treatment by Rudolf Steiner (1861-1925) [4], founder of anthroposophy. He recommended a drug extract produced in a complicated manufacturing process combining sap from mistletoe harvested in the winter and summer [5]. Based on his recommendations, several Anthroposophic doctors have treated their cancer patients with these extracts within the last century, but published - if at all - just some field reports. Moreover, pharmacological studies on the suggested anti-tumour effects of were completely lacking. Meanwhile, clinical evaluations of mistletoe as an adjuvant cancer treatment have expanded. During the 1960s, Vester and Nienhaus isolated carcinostatic protein fractions which were recognized later as the cytotoxic viscotoxins and mistletoe lectins [6]. Recent scientific research has confirmed the folklore with evidence that mistletoe extracts (1) induce apoptosis, (2) stimulate immunocompetent cells, and (3) protect the DNA of mononuclear cells (for review see [7,8]). Several experiments using tumour-bearing animals showed impressive reduction of tumour growth and/or increased survival with the application of mistletoe therapy (for review see [7-9]). The cytotoxic effects were clearly related to the viscotoxins and cytotoxic mistletoe lectins, while the immuno-modulating effects were ascribed to the mistletoe lectins, poly-/oligosaccharides, viscotoxins and several other components (reviewed in [7-10]). Results from in vitro studies and animal models indicate that the direct application of VA-E and their specific components (i.e., the cytotoxic mistletoe lectins) results in a destruction of tumours and metastases, and in an increased survival of the animals. Thus one may conclude that the intratumoural injection might be an effective route of application. Nevertheless, mistletoe extracts are recommended (and authorized) to be applied subcutaneously and not intratumourally. Moreover, there are several whole plant extracts from Viscum album on the market which differ with respect to the extraction process and thus relative proportions of their constituents (i.e., the Anthroposophic manufacturers mix the mistletoe saps of the summer and winter harvest by complicated procedures: Abnoba extracts are produced by aqueous maceration of fresh plant material; Helixor and Isorel extracts are produced by cold water extraction; Iscador extracts are produced by fermentation of the plant material; Iscucin is produced in accordance with the German Homeopathic Pharmacopoeia; the phytotherapeutic companies produce the Eurixor and Lectinol extracts by an aqueous extraction of the fresh plant material harvested from poplars during the winter season) [11]. Due to this diversity of mistletoe products and their proportions of pharmacologically relevant constituents, the interpretation of clinical studies is difficult. Consequently it is not too surprising that ante ceded reviews on the clinical effects of mistletoe extracts in cancer patients, which summarizes a mixture of studies with different designs and plant extracts used, are conflicting in their results [12-17]. For this review we decided to focus on the survival associated with the most commonly used mistletoe extracts which is covered by a large spectrum of published studies, the fermented plant extract Iscador (WELEDA AG, Switzerland). This whole plant extract is produced from fresh leafy shoots and fruits of the summer and winter harvest, is rich on mistletoe lectins and viscotoxins [11,18], and is recommended to be applied 2-3 times per week subcutaneously. We intended to determine the effectiveness of the VA-E Iscador in the treatment of patients with cancer with respect to survival. |