Preparations from the European mistletoe (Viscum album L.) are among the most prescribed drugs in cancer patients in several European countries. The most common brand names are Iscador, Helixor and Viscum Album. Proponents claim that mistletoe extracts stimulate the immune system, improve survival, enhance quality of life and reduce adverse effects of chemo- and radiotherapy in cancer patients. Critics claim that there is still not evidence to support such claims.
Controlled Clinical Trials
In a randomized controlled study from 2008 on altogether 508 patients Iscador was shown to prolong overall survival of corpus uteri cancer patients. Psychosomatic self-regulation as a measure of autonomous coping with the disease, rised significantly more under Iscador therapy than under conventional therapy alone at a follow up of 12 months.
Treatment with HELIXOR proved to be beneficial for breast cancer patients since it significantly improved quality of life and significantly reduced persistant signs/symptoms of the disease/treatment during the validated aftercare period of approximately five years in 167 patients treated with Helixor.
In an open study from 2008 33 patients with primary breast cancer receiving adjuvant chemotherapy and simultaneous treatment with Iscador was compared with 33 controls without mistletoe therapy. Reductions in quality of life seemed to be smaller during add-on-therapy with mistletoe. Laboratory parameters showed no difference compared to the control group.Mistletoe patients showed better quality of life and a reduction of in the need of symptom relieving glucocorticoid(cortisone) cotreatment.
A study on altogether 10 patients with early stage cervix cancer and healthy volunteers showed that dose-escalation of Iscador reduces the monocyte-related clinical side effects, like temperature increase and skin reactions. The most interesting clinical long-term effect is the bystander stimulation of various memory T cells that might mediate in vivo antitumor and antiinfectious T-cell response under mistletoe-extract immunization.
In three controlled cohort studies with altogether 374 patients, Iscador may have the effect of prolonging overall survival of cervical cancer patients. In the short term, psychosomatic self-regulation increases more markedly under complementary Iscador therapy than under conventional therapy alone.
Grossarth et al found in 2006 that Iscador showed a clinically relevant effect on breast tumor progression as measured by overall survival as well as by the time to recurrences, lymphatic or distant metastases on 244 patients with breast cancer. In the short term, psychosomatic self-regulation increased more markedly under complementary Iscador therapy than under conventional therapy alone.
Meta-analysis and Review Articles
A Cochrane review from 2008 found that there was not enough evidence to reach clear conclusions about the effects on any of these outcomes and it is therefore not clear to what extent the application of mistletoe extracts translates into improved symptom control, enhanced tumour response or prolonged survival. Adverse effects of mistletoe extracts were reported, but appeared to be dose-dependent and primarily confined to reactions at injection site and mild, transient flu-like symptoms. In the absence of good quality, independent trials, decisions about whether mistletoe extracts are likely to be beneficial for a particular problem should rely on expert judgement and practical considerations.
Prof Edzard Ernst stated in 2006 that mistletoe has been tested extensively as a treatment for cancer, but the most reliable randomised controlled trials fail to show benefit, and some reports show considerable potential for harm. The costs of regular mistletoe injections are high. I therefore recommend mistletoe as a Christmas decoration and for kissing under but not as an anticancer drug. At the risk of upsetting many proponents of alternative medicine, I also contend that intuition is no substitute for evidence.
Other Interesting Articles
Bar sela et al found in 2006 that installation of Iscador M into the peritoneal cavity may reduce the need for repeated punctures.