[Adjuvant simultaneous mistletoe chemotherapy in breast cancer--influence on immunological parameters, quality of life and tolerability]

Mistletoe Extract in Patients With Advanced Pancreatic Cancer: a Double-Blind, Randomized, Placebo-Controlled Tial (MISTRAL)

BACKGROUND

Patients with advanced pancreatic cancer have limited survival and few treatment options. We studied whether mistletoe extract (ME), in addition to comprehensive oncological treatment and palliative care, prolongs overall survival (OS) and improves health-related quality of life (HRQoL).

METHODS

The double-blind, placebo-controlled MISTRAL trial was conducted in Swedish oncology centers. The main inclusion criteria were advanced exocrine pancreatic cancer and Eastern Cooperative Oncology Group (ECOG) performance status 0-2. The subjects were randomly assigned to ME (n=143) or placebo (n=147) and were stratified by study site and by eligibility (yes/no) for palliative chemotherapy (June 2016-December 2021). ME or placebo was injected subcutaneously three times a week for nine months. The primary endpoint was overall survival (OS); one of the secondary endpoints was the HRQoL dimension global health/QoL (EORTC-QLQ-C30), as assessed at seven time points over nine months. Trial registration: EudraCT 2014-004552-64, NCT02948309.

RESULTS

No statistically significant benefit of adding ME to standard treatment was seen with respect to either OS or global health/ QoL. The adjusted hazard ratio for OS was 1.13 [0.89; 1.44], with a median survival time of 7.8 and 8.3 months for ME and placebo, respectively. The figures for the HRQoL dimension "global health/QoL" were similar in the two groups (p=0.86). The number, severity, and outcome of the reported adverse events were similar as well, except for more common local skin reactions at ME injection sites (66% vs. 1%).

CONCLUSION

ME is unlikely to have a clinically significant effect on OS or the HRQoL dimension global health/QoL when administered in patients with advanced pancreatic cancer in addition to comprehensive cancer care.

Natural products derived from medicinal plants and microbes might act as a game-changer in breast cancer: a comprehensive review of preclinical and clinical studies

Breast cancer (BC) is the most prevalent neoplasm among women. Genetic and environmental factors lead to BC development and on this basis, several preventive - screening and therapeutic interventions have been developed. Hormones, both in the form of endogenous hormonal signaling or hormonal contraceptives, play an important role in BC pathogenesis and progression. On top of these, breast microbiota includes both species with an immunomodulatory activity enhancing the host's response against cancer cells and species producing proinflammatory cytokines associated with BC development. Identification of novel multitargeted therapeutic agents with poly-pharmacological potential is a dire need to combat advanced and metastatic BC. A growing body of research has emphasized the potential of natural compounds derived from medicinal plants and microbial species as complementary BC treatment regimens, including dietary supplements and probiotics. In particular, extracts from plants such as Artemisia monosperma Delile, Origanum dayi Post, Urtica membranacea Poir. ex Savigny, Krameria lappacea (Dombey) Burdet & B.B. Simpson and metabolites extracted from microbes such as Deinococcus radiodurans and Streptomycetes strains as well as probiotics like Bacillus coagulans and Lactobacillus brevis MK05 have exhibited antitumor effects in the form of antiproliferative and cytotoxic activity, increase in tumors' chemosensitivity, antioxidant activity and modulation of BC - associated molecular pathways. Further, bioactive compounds like 3,3'-diindolylmethane, epigallocatechin gallate, genistein, rutin, resveratrol, lycopene, sulforaphane, silibinin, rosmarinic acid, and shikonin are of special interest for the researchers and clinicians because these natural agents have multimodal action and act via multiple ways in managing the BC and most of these agents are regularly available in our food and fruit diets. Evidence from clinical trials suggests that such products had major potential in enhancing the effectiveness of conventional antitumor agents and decreasing their side effects. We here provide a comprehensive review of the therapeutic effects and mechanistic underpinnings of medicinal plants and microbial metabolites in BC management. The future perspectives on the translation of these findings to the personalized treatment of BC are provided and discussed.

Quality of Life in Breast Cancer Patients Treated With Mistletoe Extracts: A Systematic Review and Meta-Analysis

BACKGROUND

Breast cancer is the most common cancer type in women and quality of life an essential part of patients' well-being. Although the treatment with mistletoe extracts is covered by multiple cancer guidelines and reviews, it is uncertain whether mistletoe extracts can improve the quality of life in breast cancer patients. We therefore performed a systematic review and meta-analysis on this topic.

METHODS

This systematic review included randomized clinical trials (RCTs) and non-randomized studies of intervention (NRSIs) comparing the quality of life in breast cancer patients treated with mistletoe extracts as add-on therapy to control groups treated conventionally. We searched previous systematic reviews and multiple databases until January 2023. We conducted a meta-analysis and assessed the risk of bias according to the Cochrane Handbook via RoB 2 and ROBINS-I and the certainty of evidence via GRADE, respectively.

RESULTS

Nine RCTs and 7 NRSIs with 833 and 2831 participants, respectively, were included. The pre-post changes for the quality of life resulted in a pooled standardized mean difference for RCTs of SMD = 0.61 (95% CI 0.47-0.75; P < .0001) and for retrospective NRSIs of SMD = 0.46 (95% CI 0.10-0.82; P = .01). The risk of bias was low to high for the RCTs and serious for all NRSIs. The certainty of evidence was moderate for RCTs and very low for NRSIs.

DISCUSSION

Our results indicate a clinically relevant, medium-sized effect of mistletoe extracts on the quality of life in breast cancer patients which may be based on the immunomodulating effects of mistletoe extracts during chemotherapy. The limitations of evidence include the risk of bias which is mainly caused by the difficulty of blinding. Further RCTs and real-world evidence need to confirm this result, especially in the setting of neoadjuvant chemotherapy and in breast cancer survivors.

Systematic analysis of mistletoe prescriptions in clinical studies

Purpose

Mistletoe treatment is discussed controversial as a complementary treatment for cancer patients. Aim of this systematic analysis is to assess the concept of mistletoe treatment in the clinical studies with respect to indication, type of mistletoe preparation, treatment schedule, aim of treatment, and assessment of treatment results.

Methods

In the period from August to December 2020, the following databases were systematically searched: Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PsycINFO, CINAHL, and “Science Citation Index Expanded” (Web of Science). We assessed all studies for study types, methods, endpoints and mistletoe preparations including their ways of application, host trees and dosage schedules.

Results

The search concerning mistletoe therapy revealed 3296 hits. Of these, 102 publications and at total of 19.441 patients were included. We included several study types investigating the application of mistletoe in different groups of participants (cancer patients of any type of cancer were included as well as studies conducted with healthy volunteers and pediatric patients). The most common types of cancer were breast cancer, pancreatic cancer, colorectal cancer and malignant melanoma. Randomized controlled studies, cohort studies and case reports make up most of the included studies. A huge variety was observed concerning type and composition of mistletoe extracts (differing pharmaceutical companies and host trees), ways of applications and dosage schedules. Administration varied e. g. between using mistletoe extract as sole treatment and as concomitant therapy to cancer treatment. As the analysis of all studies shows, there is no relationship between mistletoe preparation used, host tree and dosage, and cancer type.

Conclusions

Our research was not able to deviate transparent rules or guidelines with respect to mistletoe treatment in cancer care.

Cancer-related fatigue in patients treated with mistletoe extracts: a systematic review and meta-analysis

PURPOSE

Cancer-related fatigue remains one of the most prevalent and distressing symptoms experienced by cancer patients. Effective treatments for cancer-related fatigue are needed. The objective of this meta-analysis is to determine the impact of mistletoe extracts as a pharmacological treatment for the management of cancer-related fatigue.

METHODS

We included randomized clinical trials (RCTs) and non-randomized studies of interventions (NRSIs) in cancer patients. Inclusion criteria were cancer-related fatigue severity or prevalence as an outcome and testing of mistletoe extracts compared to control groups. We searched Medline (EuropePMC), Embase, the Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, and opengrey.org through October 2020. We assessed the risk of bias using the Cochrane risk of bias tools for RCTs and NRSIs and conducted a meta-analysis.

RESULTS

We performed one meta-analysis with 12 RCTs, including 1494 participants, and one meta-analysis with seven retrospective NRSIs, including 2668 participants. Heterogeneity between the studies was high in both meta-analyses. Most studies had a high risk of bias. A random-effects model showed for RCTs a standardized mean difference of -0.48 (95% confidence interval -0.82 to -0.14; p = 0.006) and for NRSIs an odds ratio of 0.36 (95% confidence interval 0.20 to 0.66; p = 0.0008).

CONCLUSION

Treatment with mistletoe extracts shows a moderate effect on cancer-related fatigue of similar size to physical activity. These results need to be confirmed by more placebo-controlled trials. Future trials should investigate different treatment durations and their effect on cancer-related fatigue in post-treatment cancer survivors.

TRIAL REGISTRATION

This meta-analysis has been registered under the PROSPERO registration number CRD42020191967 on October 7, 2020.

Additional treatment with mistletoe extracts for patients with breast cancer compared to conventional cancer therapy alone - efficacy and safety, costs and cost-effectiveness, patients and social aspects, and ethical assessment

Background

Chemotherapy is often used in the treatment of breast cancer in women. Side effects such as diarrhea, fatigue, hair loss, fever or disturbances in blood formation impair the women's quality of life. An essential treatment goal of the accompanying mistletoe therapy (MT) used in complementary medicine is to improve the health-related quality of life during cancer therapy.

Aim and methods

The HTA report on which this article is based examines the medical efficacy and safety, costs and cost-effectiveness, patient and social aspects, and ethical aspects of MT in women with breast cancer. Systematic reviews were conducted for this purpose. The search period of the literature search ranged from 2004 to October 2020.

Results

A total of 2 evidence-based medical guidelines, 3 randomized trials assessing efficacy and 1 additional non-randomized intervention trial, as well as 3 observational studies assessing safety, a cost analysis, 12 cross-sectional studies on patient aspects and 17 articles on ethical evaluation were included. Improvements in health-related quality of life compared to the control group were small to moderate. Due to the high risk of bias in the studies, it is possible that the difference is not caused by MT. One study with a small sample size showed no effect on progression-free survival after 5 years. Studies on the effect of MT on overall survival are lacking. In seven studies, local skin reactions of low and moderate severity were reported in a median of 25% (range 5 to 94%) of patients, and mild to moderate systemic reactions in a median of 2% (range 0 to 8%) of patients. A comparative cost analysis from Germany reported significantly lower medical costs within 5 years after surgery for patients with MT than for patients without MT, but the underlying observational study did not control for systematic bias. With regard to patient aspects, the frequency of use and the reasons for use from the patient's or practitioner's point of view were mainly investigated. A median of 25% (range 7 to 46%) of patients with breast cancer and 29% (range 29 to 79%) of treatment providers use MT. The main motivations of patients for use were to reduce side effects, strengthen the immune system and take an active role in the treatment process. Patients felt insufficiently advised. Studies on other aspects are lacking. The ethical evaluation was able to identify 6 overarching themes; the central challenge is the insufficient evidence on efficacy and safety.

Quality of life in cancer patients treated with mistletoe: a systematic review and meta-analysis

BACKGROUND

Mistletoe extracts are used as an adjunct therapy for cancer patients, but there is dissent as to whether this therapy has a positive impact on quality of life (QoL).

METHODS

We conducted a systematic review searching in several databases (Medline, Embase, CENTRAL, CINAHL, PsycInfo, Science Citation Index, clinicaltrials.gov, opengrey.org ) by combining terms that cover the fields of "neoplasm", "quality of life" and "mistletoe". We included prospective controlled trials that compared mistletoe extracts with a control in cancer patients and reported QoL or related dimensions. The quality of the studies was assessed with the Cochrane Risk of Bias tool version 2. We conducted a quantitative meta-analysis.

RESULTS

We included 26 publications with 30 data sets. The studies were heterogeneous. The pooled standardized mean difference (random effects model) for global QoL after treatment with mistletoe extracts vs. control was d = 0.61 (95% CI 0.41-0.81, p < 0,00001). The effect was stronger for younger patients, with longer treatment, in studies with lower risk of bias, in randomized and blinded studies. Sensitivity analyses support the validity of the finding. 50% of the QoL subdomains (e.g. pain, nausea) show a significant improvement after mistletoe treatment. Most studies have a high risk of bias or at least raise some concern.

CONCLUSION

Mistletoe extracts produce a significant, medium-sized effect on QoL in cancer. Risk of bias in the analyzed studies is likely due to the specific type of treatment, which is difficult to blind; yet this risk is unlikely to affect the outcome.

PROSPERO REGISTRATION

CRD42019137704 .

Preclinical and clinical effects of mistletoe against breast cancer

Breast cancer is among the most frequent types of cancer in women worldwide. Current conventional treatment options are accompanied by side effects. Mistletoe is amongst the important herbal medicines traditionally used as complementary remedies. An increasing number of studies have reported anticancer activity of mistletoe extracts on breast cancer cells and animal models. Some recent evidence suggests that cytotoxic activity of mistletoe may be mediated through different mechanisms. These findings provide a good base for clinical trials. Various studies on mistletoe therapy for breast cancer patients revealed similar findings concerning possible benefits on survival time, health-related quality of life (HRQoL), remission rate, and alleviating adverse reactions to conventional therapy. This review provides an overview of the recent findings on preclinical experiments and clinical trials of mistletoe for its cytotoxic and antitumor activity and its effect on HRQoL in breast cancer patients. Moreover, studies investigating molecular and cellular mechanisms underlying antitumor activity of mistletoe are discussed in this paper. The analyzed trials provided evidence that there might be a combination of pharmacological and motivational aspects mediated by the mistletoe extract application which may contribute to the clinical benefit and positive outcome such as improved HRQoL and self-regulation in breast cancer patients.

Barriers and challenges in integration of anthroposophic medicine in supportive breast cancer care

In the last decade, more and more oncology centers are challenged with complementary medicine (CM) integration within supportive breast cancer care. Quality of life (QOL) improvement and attenuation of oncology treatment side effects are the core objectives of integrative CM programs in cancer care. Yet, limited research is available on the use of specific CM modalities in an integrative setting and on cancer patients’ compliance with CM consultation. Studies are especially warranted to view the clinical application of researched CM modalities, such as anthroposophic medicine (AM), a unique CM modality oriented to cancer supportive care. Our objective was to characterize consultation patterns provided by physicians trained in CM following oncology health-care practitioners’ referral of patients receiving chemotherapy. We aimed to identify characteristics of patients who consulted with AM and to explore patients’ compliance to AM treatment. Of the 341 patients consulted with integrative physicians, 138 were diagnosed with breast cancer. Following integrative physician consultation, 56 patients were advised about AM treatment and 285 about other CM modalities. Logistic multivariate regression model found that, compared with patients receiving non-anthroposophic CM, the AM group had significantly greater rates of previous CM use [EXP(B) = 3.25, 95% C.I. 1.64-6.29, p = 0.001] and higher rates of cancer recurrence at baseline (p = 0.038). Most AM users (71.4%) used a single AM modality, such as mistletoe (viscum album) injections, oral AM supplements, or music therapy. Compliance with AM modalities following physician recommendation ranged from 44% to 71% of patients. We conclude that AM treatment provided within the integrative oncology setting is feasible based on compliance assessment. Other studies are warranted to explore the effectiveness of AM in improving patients’ QOL during chemotherapy.

Five-year follow-up of patients with early stage breast cancer after a randomized study comparing additional treatment with viscum album (L.) extract to chemotherapy alone

Additional therapy with extracts of Viscum album [L.] (VaL) increases the quality of life of patients suffering from early stage breast cancer during chemotherapy. In the current study patients received chemotherapy, consisting of six cycles of cyclophosphamide, anthracycline, and 5-Fluoro-Uracil (CAF). Two groups also received one of two VaL extracts differing in their preparation as subcutaneous injection three times per week. A control group received CAF with no additional therapy. Six of 28 patients in one of the VaL groups and eight of 29 patients in the control group developed relapse or metastasis within 5 years. Subgroup analysis for hormone- and radiotherapy also showed no difference between groups. Additional VaL therapy during chemotherapy of early stage breast cancer patients appears not to influence the frequency of relapse or metastasis within 5 years.

Safety of higher dosages of Viscum album L. in animals and humans--systematic review of immune changes and safety parameters

BACKGROUND

Viscum album L extracts (VAE, mistletoe) and isolated mistletoe lectins (ML) have immunostimulating properties and a strong dose-dependent cytotoxic activity. They are frequently used in complementary cancer treatment, mainly to improve quality of life, but partly also to influence tumour growth, especially by injecting VAE locally and in high dosage. The question is raised whether these higher dosages can induce any harm or immunosuppressive effects.

METHODS

Systematic review of all experiments and clinical studies investigating higher dosages of VAE in animals and humans (Viscum album > 1 mg in humans corresponding to > 0.02 mg/kg in animals or ML > 1 ng/kg) and assessing immune parameters or infections or adverse drug reactions.

RESULTS

69 clinical studies and 48 animal experiments reported application of higher doses of VAE or ML and had assessed immune changes and/or harm. In these studies, Viscum album was applied in dosages up to 1500 mg in humans and 1400 mg/kg in animals, ML was applied up to 6.4 μg/kg in humans and in animals up to 14 μg/kg subcutaneously, 50 μg/kg nasally and 500 μg/kg orally. A variety of immune parameters showed fluctuating or rising outcomes, but no immunosuppressive effect. Side effects consisted mainly of dose-dependent flu-like symptoms (FLS), fever, local reactions at the injection site and various mild unspecific effects. Occasionally, allergic reactions were reported. After application of high doses of recombinant ML, reversible hepatotoxicity was observed in some cases.

CONCLUSIONS

Application of higher dosages of VAE or ML is not accompanied by immunosuppression; altogether VAE seems to exhibit low risk but should be monitored by clinicians when applied in high dosages.

An exploratory study on the quality of life and individual coping of cancer patients during mistletoe therapy

BACKGROUND

Although several clinical studies have shown that mistletoe therapy (MT, Viscum album) may improve cancer patients' quality-of-life (QoL), qualitative information on the improvement's nature is still lacking.

DESIGN

This exploratory, prospective, cohort-study comprised 25 patients with different types of cancer. The patients filled in the EORTC QLQ-C30 Version 3.0 questionnaire at the beginning of MT (n = 25) and three months later (n = 21). If patients agreed, they were interviewed on both occasions (n = 17); the interviews were transcribed verbatim and submitted to a qualitative content analysis (n = 12).

RESULTS

Analysis of the questionnaires showed significant improvements in several subscales during MT. The interviews analysis revealed that most patients adopted the MT with a supportive goal, with all patients undergoing conventional therapies. After three months of MT, most interviewed patients revealed higher vitality and autonomy. MT was often seen as a chance to make an own personal contribution to the therapy, which was particularly appreciated in cases in which no conventional therapy was (anymore) advised. Concrete personal achievements such as changes in the private and/or in the professional environment were spontaneously mentioned by the patients, illustrating and corroborating their improvements in QoL.

CONCLUSION

Our results show that the patients experienced an improvement of QoL during MT. This therapy seemed to offer a platform for an integrative coping with the disease, which might be important in reconciling the perceived shock of an existential illness with a good QoL.

Review article: Influence of Viscum album L (European mistletoe) extracts on quality of life in cancer patients: a systematic review of controlled clinical studies

OBJECTIVE

To evaluate controlled clinical studies on the efficacy and effectiveness of Viscum album for quality of life (QoL) in cancer.

MATERIALS AND METHODS

The authors conducted a search of 7 electronic databases and reference lists and had extensive consultations with experts. They carried out a criteria-based assessment of methodological study quality.

RESULTS

The authors identified 26 randomized controlled trials (RCTs) and 10 non-RCTs that investigated the influence of V album extracts (VAEs) on QoL in malignant diseases; 26 studies assessed patient-reported QoL. Questionnaires were mostly well established and validated. Half of the studies investigated VAEs concomitant with chemotherapy, radiotherapy, or surgery. Some studies were well designed, whereas others had minor or major methodological weaknesses. Among the 26 RCTs, 22 reported a QoL benefit, 3 indicated no difference, and 1 did not report any result. All the non-RCTs reported a QoL benefit. Of the studies with higher methodological quality, most reported a benefit, whereas 1 found no difference. Improvements were mainly in regard to coping, fatigue, sleep, exhaustion, energy, nausea, vomiting, appetite, depression, anxiety, ability to work, and emotional and functional well-being in general and, less consistently, in regard to pain, diarrhea, general performance, and side effects of conventional treatments. VAEs were well tolerated.

CONCLUSIONS

VAEs seem to have an impact on QoL and reduction of side effects of conventional therapies (chemotherapy, radiation) in experimental trials as well as in routine daily application. The influence on fatigue especially should be investigated further.

Viscum album L. extracts in breast and gynaecological cancers: a systematic review of clinical and preclinical research

BACKGROUND

Viscum album L. extracts (VAE, European mistletoe) are a widely used medicinal plant extract in gynaecological and breast-cancer treatment.

METHODS

Systematic review to evaluate clinical studies and preclinical research on the therapeutic effectiveness and biological effects of VAE on gynaecological and breast cancer. Search of databases, reference lists and expert consultations. Criteria-based assessment of methodological study quality.

RESULTS

19 randomized (RCT), 16 non-randomized (non-RCT) controlled studies, and 11 single-arm cohort studies were identified that investigated VAE treatment of breast or gynaecological cancer. They included 2420, 6399 and 1130 patients respectively. 8 RCTs and 8 non-RCTs were embedded in the same large epidemiological cohort study. 9 RCTs and 13 non-RCTs assessed survival; 12 reported a statistically significant benefit, the others either a trend or no difference. 3 RCTs and 6 non-RCTs assessed tumour behaviour (remission or time to relapse); 3 reported statistically significant benefit, the others either a trend, no difference or mixed results. Quality of life (QoL) and tolerability of chemotherapy, radiotherapy or surgery was assessed in 15 RCTs and 9 non-RCTs. 21 reported a statistically significant positive result, the others either a trend, no difference, or mixed results. Methodological quality of the studies differed substantially; some had major limitations, especially RCTs on survival and tumour behaviour had very small sample sizes. Some recent studies, however, especially on QoL were reasonably well conducted. Single-arm cohort studies investigated tumour behaviour, QoL, pharmacokinetics and safety of VAE. Tumour remission was observed after high dosage and local application. VAE application was well tolerated. 34 animal experiments investigated VAE and isolated or recombinant compounds in various breast and gynaecological cancer models in mice and rats. VAE showed increase of survival and tumour remission especially in mice, while application in rats as well as application of VAE compounds had mixed results. In vitro VAE and its compounds have strong cytotoxic effects on cancer cells.

CONCLUSION

VAE shows some positive effects in breast and gynaecological cancer. More research into clinical efficacy is warranted.