Mistletoe Therapy in Cancer Care
Mistletoe therapy is a complimentary cancer therapy utilizing a water extract of the mistletoe leaf and berry. Mistletoe is the common name for a family of semi-parasitic plants containing over 1000 species. The scientific name for the plant family is Viscum. The species of Viscum shown to have benefit in the setting of cancer is album or Viscum album; named for the white berry produced by this species.
For centuries, mistletoe has been used to address various health conditions. The Druids used mistletoe both medicinally and ritually, considering it sacred because it grew high in the trees, suspended between heaven and earth. Rudolph Steiner, the father of Anthroposophical medicine, was a pioneer in using mistletoe for cancer treatment. His observations of the plant blooming in winter out of rhythm with the host tree, and the slow, constant growing and dividing in a circular mass resembled the characteristics of a cancer tumor. These similarities inspired his practice to use mistletoe in the cancer setting which has been subsequently validated by research.
Characteristics of Mistletoe
Mistletoe is considered semi-parasitic because it invades the tree only to the depth of the bark, not into the wood/cambium of the tree, preventing the destruction of the tree. Mistletoe uses multiple tree species as its host, including fir, pine, and apple. It lacks a typical root system, instead using a root-like projection called a haustorium, to penetrate the bark of the tree to access essential nutrients. Each host tree provides a different cocktail of nutrients creating unique medicinal properties in the mistletoe plants growing on them. Mistletoe extracts are characterized by their host tree and the varied extracts have specific applications based on types of tumors and a person’s specific health considerations.
Mistletoe was first used in cancer therapy in 1922 when few viable treatment options existed. Ita Wegman, MD (Head of the Clinical-Therapeutic Institute in Switzerland), is credited with developing the first mistletoe injection products. The introduction of radiation therapy in 1937 and chemotherapy in the 1940’s revolutionized and changed the treatment of cancer to this day. However, as will be presented below, there is also a role for mistletoe in the integrative treatment of cancer.
The Role of Mistletoe in Cancer Therapy
Mistletoe is one of the most studied integrative cancer therapies in the world with over 7000 published studies documented to date, including preclinical and human trials. Mistletoe/Viscum album contains more than 500 substances in total, and more than 170 biologically-active compounds. The most important and well-researched of these compounds include mistletoe lectins and viscotoxins. These two compounds are primarily responsible for the cancer therapy benefits.
The beneficial biological actions of mistletoe in cancer therapy are numerous and varied. Viscotoxins disrupt cellular membranes leading to destruction of tumor cells. Mistletoe lectins exert multiple actions in the body including immune system modulation, triggering programmed cell death of cancer cells, and blocking the formation of new blood vessels which support tumor growth. In addition, mistletoe lectins protect the DNA of healthy cells.
Multiple human trials have been conducted to assess the effectiveness of mistletoe therapy in integrative cancer treatment. Benefits seen in clinical trials include reduction of chemotherapy-induced side effects: fatigue, nausea, vomiting, decreased appetite, liver toxicity, and immune suppression. Improved quality of life, improved pain, and trends toward improved survival have been demonstrated in human trials as well. Through improving treatment side effects, the incorporation of mistletoe may also improve compliance and completion of conventional treatment, improving overall response to treatment.
A 2004 retrospective study of 1442 women with breast cancer compared women receiving conventional treatment alone with women receiving conventional treatment and mistletoe therapy. The women who received the additional mistletoe experienced fewer side effects from the chemotherapy. A systematic review of 26 randomized controlled trials found an improved quality of life in 22 of the 26 trials. Chemotherapy side effects were reduced as well.
Benefit from mistletoe therapy has been seen in the following types of cancer: breast, lung, colon, pancreatic, stomach, ovarian, cervical, melanoma, and others. Most of the research supports use in the setting of solid tumors (ex: breast, prostate, lung, ovarian), though there is data supporting the use in blood cancers (leukemia) as well, particularly for reducing side effects.
Mistletoe is the most widely used complementary cancer therapy in Europe and is approved for palliative care in many European countries. However, mistletoe remains outside of the mainstream cancer treatment paradigm in the U.S. With continued research in the U.S. hopefully the status will shift.
Johns Hopkins Kimmel comprehensive cancer center is currently enrolling a Phase I clinical trial to assess the safety of intravenous mistletoe therapy. You may visit clinicaltrials.gov for more information.
Cancer Management and Treatment
Integrative and holistic cancer treatment incorporates a five-pronged approach to cancer management and treatment, including the following:
- Conventional Treatment (chemotherapy/radiation/targeted therapy)
- Nutraceuticals/Natural Supplements
- Dietary Recommendations
- Lifestyle Counseling
- Mental/Emotional/Spiritual health
Mistletoe therapy falls under both the nutraceutical and mental/emotional/spiritual groups. The use of mistletoe causes biochemical and immune responses within the body, evidenced by skin reactions and lab results. In addition, based on anthroposophical medicine philosophy, mistletoe induces an energetic healing effect on the body and cancer process.
Although occasionally used as a stand-alone treatment, Mistletoe therapy provides the greatest benefit when used within an integrative setting, alongside conventional treatment. Using mistletoe after the completion of conventional treatment may reduce the risk of disease recurrence. In addition, mistletoe therapy offers benefit in precancerous conditions including atypical ductal hyperplasia and cervical dysplasia. Although more nuanced, there may also be a role of mistletoe therapy in some auto-immune conditions.
The FDA (Federal Drug Administration) categorizes mistletoe therapy as a generally recognized as safe (GRAS) homeopathic preparation. A recent study found that mistletoe therapy did not interact with drug metabolism enzymes and concluded that concurrent use of mistletoe with medications is likely safe (BMC Complementary and Alternative Medicine volume 17, Article number:521 (2017). The trials combining mistletoe with conventional treatment found trends towards prolonged survival demonstrating benefit rather than interaction with the treatments.
Mistletoe may be administered via subcutaneous injection or intravenously; the most commonly used application is subcutaneous. Side effects associated with injection include redness at the side of injection, mild fever, headache, and chills. Rarely allergic reactions and elevated fevers or chills occur. Oral administration of mistletoe therapy is not recommended due to potential toxicity and lack of benefit.
Contraindications to mistletoe therapy include presence of high fever or acute infection, severely low platelets, certain auto-immune conditions, pregnancy, allergy to mistletoe, and bone marrow transplant.
Mistletoe therapy is not an FDA approved treatment and thus not offered as a part of standard cancer treatment in the US at this time. Mistletoe therapy may only be used under the care of a qualified and licensed healthcare provider. In the US, naturopathic doctors and other licensed complimentary healthcare providers offer mistletoe therapy.
Renée Lang, ND, FABNO, MPH is licensed as a naturopathic doctor in the state of Maine and is board certified in naturopathic oncology (FABNO). She received her naturopathic doctorate from National College of Natural Medicine in 2003 and holds a B.S. in Conservation and Resource Studies from the University of California at Berkeley. In addition, she received her MPH in 2013 from Johns Hopkins Bloomberg School of Public Health, with additional certification in environmental and occupational health. As a Reiki Master and Shamanic practitioner, Dr. Lang has been incorporating these healing techniques in her since 2002. Dr. Lang currently sees patients at her office in the Parkview Office Building in Brunswick, ME. From 2009-2013 she worked as a naturopathic oncology consultant at the Cancer Treatment Centers of America (CTCA) in Philadelphia. While at CTCA, Dr. Lang provided integrative naturopathic care to thousands of individuals with cancer.