Survival of cancer patients treated with mistletoe extract (Iscador): a systematic literature review

Ostermann et al., 2009 | BMC Cancer | Meta Analysis

Citation

Ostermann Thomas, Raak Christa, Büssing Arndt. Survival of cancer patients treated with mistletoe extract (Iscador): a systematic literature review. BMC Cancer. 2009-Dec-18;9:451. doi:10.1186/1471-2407-9-451

Abstract

BACKGROUND: In Europe, extracts from Viscum album (VA-E), the European white-berry mistletoe, are widely used to treat patients with cancer. METHODS: We 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. RESULTS: We 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). CONCLUSIONS: Pooled 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.

Key Findings

We 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,

Outcomes Measured

• Requires manual extraction

Population

MeSH Terms

• Complementary Therapies
• Humans
• Mistletoe
• Neoplasms
• Phytotherapy
• Plant Extracts
• Survival Rate

Evidence Classification

• Level: Meta Analysis
• Publication Types: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Systematic Review
• Vertical: mistletoe

Provenance

• PMID: 20021637
• DOI: 10.1186/1471-2407-9-451
• PMCID: PMC2804713
• Verified: 2026-04-09 via PubMed E-utilities API

Source extracted via PubMed E-utilities API on 2026-04-09