Home > Health & Wellness > Health Library > Topics in Integrative, Alternative, and Complementary Therapies (PDQ®): Integrative, alternative, and complementary therapies - Health Professional Information [NCI]
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Complementary and alternative medicine (CAM) covers a wide variety of therapies and botanicals. Integrative therapy combines standard care with CAM practices. The 2007 National Health Interview Survey reports about four out of ten adults use a CAM therapy, with the most commonly used treatments being natural products and deep breathing exercises. One large survey of cancer survivors reported on the use of complementary therapies. The therapies used most often were prayer and spiritual practice (61%), relaxation (44%), faith and spiritual healing (42%), and nutritional supplements and vitamins (40%). CAM therapies are used by 31% to 84% of children with cancer, both in and outside of clinical trials.[3,4] CAM therapies have been used in the management of side effects caused by cancer or cancer treatment.
This cancer information summary provides a brief description and a link to integrative, alternative, and complementary therapies found in PDQ summaries or NCI Fact Sheets. The links will take you to the specific PDQ summary, NCI Fact Sheet, or other PDQ summary section, providing more information and references on the topic. Refer to NCI's Office of Cancer Complementary and Alternative Medicine website for links to other resources.
Acupuncture is a part of traditional Chinese medicine practiced in China and Asia for thousands of years. It has been used clinically to manage cancer-related symptoms, treat side effects induced by chemotherapy or radiation therapy, boost blood cell count, and enhance lymphocyte and natural killer cell activity. In cancer treatment, the primary use of acupuncture is symptom management; commonly treated symptoms are cancer pain, chemotherapy-induced nausea and vomiting, and other symptoms that affect a patient's quality of life, including weight loss, anxiety, depression, insomnia, poor appetite, and gastrointestinal symptoms (constipation and diarrhea). Refer to the PDQ summary on Acupuncture for more information.
Black cohosh is a substance obtained from the root of a perennial herb used in some cultures to treat a number of medical problems. Black cohosh has been studied for reducing hot flashes. Clinical trials of black cohosh that have been well designed with a randomized placebo-controlled arm have also found that black cohosh is no better than a placebo in reducing hot flashes. Refer to the Herbs/dietary supplements section in the PDQ summary on Hot Flashes and Night Sweats for more clinical trial information about black cohosh.
Cannabisand Cannabinoids (Also Known as Marijuana)
Cannabis originated in Central Asia but is grown worldwide today. In the United States, it is a controlled substance and is classified as a Schedule I agent (a drug with increased potential for abuse and no known medical use). The Cannabis plant produces a resin containing psychoactive compounds called cannabinoids. The potential benefits of medicinal Cannabis for people living with cancer include antiemetic effects, appetite stimulation, pain relief, and improved sleep. Refer to the PDQ summary on Cannabis and Cannabinoids for more information.
Essiac and Flor Essence are herbal tea mixtures originally developed in Canada. They are marketed worldwide as dietary supplements. Proponents have claimed that Essiac and Flor Essence can help detoxify the body, strengthen the immune system, and fight cancer. No controlled data are available from human studies to suggest that Essiac or Flor Essence can be effective in the treatment of patients with cancer. Refer to the PDQ summary on Essiac/Flor Essence for more information.
Flaxseed comes from the seed of the flax plant and is a rich source of omega-3 fatty acid, fiber, and a compound called lignin. It is being studied in the prevention of several types of cancer. Flaxseed has also been studied for its effect on hot flashes. Refer to the Herbs/dietary supplements section in the PDQ summary on Hot Flashes and Night Sweats for information about clinical trials that have studied flaxseed.
Ginger is an herb with a root that has been used in cooking and by some cultures to treat nausea, vomiting, and certain other medical conditions. It has been studied for reducing nausea in cancer patients. Refer to the Ginger section in the PDQ summary on Nausea and Vomiting for information about randomized controlled trials of ginger in cancer patients.
Ginseng, another popular supplement used to treat fatigue, was studied in patients with cancer who were either undergoing anticancer treatment or had completed treatment. There was a significant and clinically meaningful difference favoring the ginseng group over the placebo group. Refer to the Intervention section in the PDQ summary on Fatigue for more information.
L-carnitine is a dietary supplement believed to be helpful for the treatment of cancer-related fatigue because of its role in cellular energy metabolism and its ability to decrease proinflammatory cytokines. Refer to the Intervention section in the PDQ summary on Fatigue for information about a phase III study that compared L-carnitine with placebo.
Refer to the PDQ summary on Cannabis and Cannabinoids for more information.
Milk thistle is a plant whose fruit and seeds have been used for more than 2,000 years as a treatment for liver and biliary disorders. The active substance in milk thistle is silymarin. Laboratory studies demonstrate that silymarin functions as an antioxidant, stabilizes cellular membranes, stimulates detoxification pathways, stimulates regeneration of liver tissue, inhibits the growth of certain cancer cell lines, exerts direct cytotoxic activity toward certain cancer cell lines, and may increase the efficacy of certain chemotherapy agents. Refer to the PDQ summary on Milk Thistle for more information.
Mistletoe is a semiparasitic plant that has been used for centuries to treat numerous human ailments. It is used commonly in Europe, where a variety of different extracts are manufactured and marketed as injectable prescription drugs. These injectable drugs are not available commercially in the United States and are not approved as a treatment for people with cancer. Refer to the PDQ summary on Mistletoe Extracts for more information.
PC-SPES is a patented mixture of eight herbs. Each herb used in PC-SPES has been reported to have anti-inflammatory, antioxidant, or anticarcinogenic properties. PC-SPES was recalled and withdrawn from the market because certain batches were contaminated with Food and Drug Administration–controlled prescription drugs. The manufacturer is no longer in operation, and PC-SPES is no longer being made. Refer to the PDQ summary on PC-SPES for more information.
St. John's wort
There continue to be high levels of enthusiasm for the use of herbs and dietary supplements for controlling symptoms and improving health-related quality of life and well-being. One popular herbal agent that has been used to treat depression is St. John's wort, a plant with Greek origins. The major active constituents in St. John's wort are hypothesized to be melatonin, hypericin, hyperforin, and adhyperforin, although hypericin may not reach sufficient concentrations in humans to have biologic activity. Hypericin is thought to be a monoamine oxidase inhibitor, while hyperforin and adhyperforin are believed to inhibit the reuptake of serotonin, dopamine, and norepinephrine.[1,2,3,4] These mechanisms of action provide the rationale for evaluating St. John's wort for depression management.
It is important that a physician knows what drugs a patient is already using before that patient begins taking St. John's wort, which decreases the effectiveness of other concomitantly administered drugs. There are two important cautions when the use of St. John's wort for depression is being considered:
During the last 25 years, many trials have compared St. John's wort with placebo, with antidepressants, and sometimes with both placebo and antidepressants. A wide range of results have emerged, from finding no differences between arms, to finding St. John's wort improving outcomes over placebo for moderate depression, to finding St. John's wort preferable to placebo in general, to finding St. John's wort equal to antidepressants in alleviating depressive symptoms.;[10,11][Level of evidence: I] Older studies comparing St. John's wort with antidepressant therapy tended to use low doses of antidepressants, and the doses of antidepressants did not titrate up by response to the usual doses used for managing depression. The best overview of the research in this area is provided in a meta-analysis of randomized controlled trials. Conclusions from this meta-analysis, which includes 37 trials, are that St. John's wort does not have a clinically important effect on major depressive disorder and that for milder depression, it may have some effect (but the effect is not large).
Side effects reported in studies of St. John's wort are minimal. One study that compared St. John's wort with sertraline and placebo found that the side effects of St. John's wort that were significantly different from those of placebo included anorgasmia, frequent urination, and swelling.[Level of evidence: I] According to a meta-analysis of randomized controlled trials, fewer patients treated with St. John's wort withdrew from trials because of adverse effects than did those treated with antidepressants.
The bottom line regarding the use of St. John's wort for the management of depression is that, despite a more tolerable side effect profile, there is some, but currently no unambiguous evidence demonstrating an advantage to using this herbal agent over approved antidepressant therapy. The data do not support a strong effect on major depressive disorder or even on mild to moderate depression. This fact, combined with concerns about drug interactions and lack of uniformity in standardization, limits the evidence which supports St. John's wort as being effective for depression management specifically in cancer patients.
Selected Vegetables/Sun's Soup
"Selected Vegetables" and "Sun's Soup" are names given to several different mixtures of vegetables and herbs that have been studied as treatments for cancer. These mixtures were developed by a single individual. Two formulations of Selected Vegetables/Sun's Soup are marketed in the United States as dietary supplements. The vegetables and herbs in Selected Vegetables/Sun's Soup are thought to have anticancer and/or immune-system–stimulating properties. Existing data supporting the effectiveness of Selected Vegetables/Sun's Soup as a treatment for cancer are limited and weak. Refer to the PDQ summary on Selected Vegetables/Sun's Soup for more information.
Aromatherapy and Essential Oils
Aromatherapy is the therapeutic use of essential oils (also known as volatile oils) from plants (flowers, herbs, or trees) for the improvement of physical, emotional, and spiritual well-being. Aromatherapy is used by cancer patients primarily as supportive care for general well-being, and with other complementary treatments (e.g., massage and acupuncture) and standard treatment. Refer to the PDQ summary on Aromatherapy and Essential Oils for more information.
Cognitive-Behavioral Therapy (CBT)
CBT is a type of psychotherapy that helps patients change behavior by changing the way they think and feel about certain things. It is used to treat mental, emotional, personality, and behavioral disorders. Components of CBT include the following:
For information about how CBT is used to treat fatigue, refer to the Cognitive Behavior Therapy section in the PDQ summary on Fatigue.
Psychotherapy for depression has been offered in a variety of forms. Most interventions have been offered in both individual and small-group formats, and have included a structured educational component about cancer or a specific relaxation component. Refer to the Psychotherapy section in the PDQ summary on Depression for more information about psychotherapy for depression. Refer to the Treatment section in the PDQ summary on Cancer-Related Post-traumatic Stress for information about the use of CBT for post-traumatic symptoms.
CBT has also shown promise for the treatment of insomnia in patients with cancer. Refer to the Management section in the PDQ summary on Sleep Disorders for information about sleep studies in cancer patients.
Hypnosis is a trance-like state in which one becomes more aware and focused and is more open to suggestion. Under hypnosis, a person can concentrate more clearly on a specific thought, feeling, or sensation without becoming distracted. Refer to the Psychosocial Interventions for Distress section in the PDQ summary on Adjustment to Cancer: Anxiety and Distress for more information about hypnosis used for pain relief.
Manual Lymphedema Therapy
Manual lymphedema therapy is a massage to encourage the flow of lymph fluid out of the affected arm or leg and move it to healthy lymph nodes, where it can drain. Refer to the Manual lymphedema therapy section in the PDQ summary on Lymphedema for more information about manual lymphedema therapy.
Qigong is a component of traditional Chinese medicine that combines movement, meditation, and controlled breathing. The intent is to improve blood flow and the flow of qi. Some trials, mostly with small sample sizes, have indicated that qigong may improve quality of life and fatigue in cancer patients. Refer to the Exercise section in the PDQ summary on Fatigue for more information about how qigong is being studied in cancer-related fatigue.
Spirituality and religion are important to most individuals in the general population, according to national surveys. In health care, concerns about spiritual or religious well-being have sometimes been viewed as an aspect of complementary and alternative medicine, but this perception may be more characteristic of providers than of patients. Refer to the PDQ summary on Spirituality in Cancer Care for information about religion, spirituality, spiritual well-being, and health.
Some trials, mostly with small sample sizes, have indicated that tai chi may improve quality of life and fatigue in cancer patients.
Yoga is an ancient system of practices used to balance the mind and body through exercise, meditation (focusing thoughts), and control of breathing and emotions. Yoga is being studied as a way to relieve stress and treat sleep problems in cancer patients. Refer to the Mindfulness-based stress reduction for survivors of breast cancer section in the PDQ summary on Adjustment to Cancer: Anxiety and Distress for information about a clinical trial that used meditation and yoga to reduce stress in breast cancer survivors.
Antioxidants and Cancer Prevention
Antioxidants are substances that may protect cells from the damage caused by unstable molecules known as free radicals. Free radical damage may lead to cancer. Antioxidants interact with and stabilize free radicals and may prevent some of the damage free radicals might otherwise cause. There has been some concern about whether antioxidants may decrease the effectiveness of chemotherapy and radiation therapy. Examples of antioxidants include beta-carotene; lycopene; vitamins C, E, and A; and other substances. Refer to the NCI Fact Sheet on Antioxidants and Cancer Prevention for more information about antioxidants.
Coenzyme Q10 is made naturally by the human body. Coenzyme Q10 helps cells to produce energy, and it acts as an antioxidant. Coenzyme Q10 has shown an ability to stimulate the immune system and to protect the heart from damage caused by certain chemotherapy drugs. No report of a randomized clinical trial of coenzyme Q10 as a treatment for cancer has been published in a peer-reviewed scientific journal. Refer to the PDQ summary on Coenzyme Q10 for more information.
Many studies suggest that the use of complementary and alternative medicine is common among prostate cancer patients, and the use of vitamins, supplements, and specific foods is frequently reported by these patients. Refer to the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for information about green tea, lycopene, modified citrus pectin (MCP), pomegranate, soy, and Zyflamend supplements used by some prostate cancer patients.
The Gerson therapy is advocated by its supporters as a method of treating cancer patients based on changes in diet and nutrient intake. An organic vegetarian diet plus nutritional and biological supplements, pancreatic enzymes, and coffee or other types of enemas are the main features of the Gerson therapy. Few clinical studies of the Gerson therapy are found in the medical literature. Refer to the PDQ summary on the Gerson Therapy for more information.
The Gonzalez regimen is a complex cancer treatment that is tailored by the practitioner for each specific patient and is currently available only to the patients of its developer. Pancreatic enzymes taken orally are the primary agents in the regimen thought to have direct antitumor effects. The regimen also includes specific diets, vitamin and mineral supplements, extracts of animal organs, and coffee enemas. Refer to the PDQ summary on the Gonzalez Regimen for more information.
Lycopene is a carotenoid found in a number of fruits and vegetables, including apricots, guava, and watermelon, but most of the lycopene consumed in the United States comes from tomato-based products. When ingested, lycopene is broken down into a number of metabolites and is thought to have various biological functions, including antioxidant capabilities. Lycopene has been investigated for its role in chronic diseases, including cardiovascular disease and cancer. Refer to the Lycopene section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for more information.
Melatonin is a hormone produced by the pineal gland during the hours of darkness, plays a major role in the sleep-wake cycle, and is linked to the circadian rhythm. Clinical studies in renal, breast, colon, lung, and brain cancer suggest that melatonin exerts anticancer effects in conjunction with chemotherapy and radiation therapy; however, evidence remains inconclusive. Refer to the Botanical/dietary supplements section in the PDQ summary on Sleep Disorders for information about how melatonin is being studied in sleep disturbances.
Modified Citrus Pectin
Citrus pectin is a complex polysaccharide found in the peel and pulp of citrus fruit and can be modified by treatment with high pH and temperature. MCP may have effects on cancer growth and metastasis through multiple potential mechanisms, as suggested in preclinical research. Some research suggests that MCP may be protective against various types of cancer, including colon, lung, and prostate cancer. Refer to the Modified Citrus Pectin section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for more information.
The pomegranate (Punica granatum L.) is native to Asia and cultivated widely throughout world. Various components of the pomegranate fruit contain bioactive compounds, including phenolics, flavonoids, and anthocyanins, some of which have antioxidant activity. Pomegranate extracts have been shown to inhibit the proliferation of human prostate cancer cells in vitro. Refer to the Pomegranate section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for more information.
Probiotics are nutritional supplements that contain a defined amount of viable microorganisms. The use of probiotic functional foods (beneficial live microorganisms) to modify gut microflora has been suggested for clinical conditions associated with diarrhea, gut-barrier dysfunction, and inflammatory response. Refer to the Management section in the PDQ summary on Gastrointestinal Complications for information about probiotics.
Selenium is an essential trace mineral involved in a number of biological processes, including enzyme regulation, gene expression, and immune function. Selenium is being studied for its role in cancer. Refer to the Selenium section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for information about studies investigating the effects of selenium on prostate cancer.
Soy comes from a plant of Asian origin that produces beans used in many food products. Soy foods (e.g., soy milk, miso, tofu, and soy flour) contain phytochemicals that may have health benefits and, among these, soy isoflavones have been the focus of most of the research. Soy is being studied for the prevention of cancer, hot flashes that occur with menopause, and osteoporosis (loss of bone density). Refer to the Soy section in the PDQ summary on Nutrition in Cancer Care for information about the use of soy in breast cancer patients. Refer to the Soy section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for information about studies investigating the effects of soy on prostate cancer.
Tea has long been regarded as an aid to good health, and many believe it can help reduce the risk of cancer. Tea contains polyphenol compounds, particularly catechins, which are antioxidants and whose biological activities may be relevant to cancer prevention. Refer to the NCI Fact Sheet on Tea and Cancer Prevention: Strengths and Limits of the Evidence for information about tea and cancer prevention.
Some observational and interventional studies suggest that green tea may have a protective effect against cardiovascular disease, and there is evidence that green tea may protect against various forms of cancer. Refer to the Green Tea section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for more information about studies investigating the effects of green tea on prostate cancer.
Vitamin C, High-Dose
Vitamin C (ascorbic acid) is an essential nutrient that has antioxidant functions, is a cofactor for several enzymes, and plays an important role in the synthesis of collagen. High-dose vitamin C has been studied as a treatment for cancer patients. Refer to the PDQ summary on High-Dose Vitamin C for more information.
Vitamin D is involved in a number of processes that are essential for good health. Vitamin D is produced by the body in response to sunlight exposure. It can also be obtained through the diet, but very few foods naturally contain vitamin D. These foods include fatty fish, fish liver oil, and eggs. Refer to the NCI Fact Sheet on Vitamin D and Cancer Prevention for information about scientific studies that have investigated the possible role of vitamin D in cancer prevention. Refer to the Vitamin D section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for information about studies investigating the effects of vitamin D on prostate cancer.
Vitamin E is a nutrient that the body needs in small amounts to stay healthy and work the way it should. It is fat-soluble (can dissolve in fats and oils) and is found in seeds, nuts, leafy green vegetables, and vegetable oils. Vitamin E boosts the immune system and helps keep blood clots from forming. It also helps prevent cell damage caused by free radicals (highly reactive chemicals). Vitamin E is being studied in the prevention and treatment of some types of cancer. It is a type of antioxidant, also called alpha-tocopherol. Refer to the Vitamin E section in the PDQ summary on Prostate Cancer, Nutrition, and Dietary Supplements for information about studies investigating the effects of vitamin E on prostate cancer. Refer to the Herbs/dietary supplements section in the PDQ summary on Hot Flashes and Night Sweats for information about hot flashes and vitamin E studies.
714-X is naturally derived camphor that is chemically modified by the introduction of a nitrogen atom. It is claimed that 714-X protects and stabilizes the immune system and restores its ability to fight cancer. No study of 714-X has been published in a peer-reviewed scientific journal to show its safety or effectiveness in treating cancer. Refer to the PDQ summary on 714-X for more information.
Antineoplastons are drugs composed of chemical compounds that are naturally present in the urine and blood. They are an experimental cancer therapy that is purported to provide a natural biochemical substance that is excreted and therefore lacking in people with cancer. Antineoplastons therapy for cancer patients is currently available only in the United States and only to the patients of its developer. Refer to the PDQ summary on Antineoplastons for more information.
Cancell/Cantron/Protocel—also known by the names Sheridan's Formula, Jim's Juice, JS-114, JS-101, 126-F, and the "Cancell-like" products Cantron and Protocel—is a liquid that has been produced in various forms principally by two manufacturers since the late 1930s. The exact composition of Cancell/Cantron/Protocel is unknown and not effective in treating any type of cancer. Refer to the PDQ summary on Cancell/Cantron/Protocel for more information.
Cartilage (Bovine and Shark)
Bovine (cow) cartilage and shark cartilage have been studied as treatments for people with cancer and other medical conditions for more than 30 years. At least three different inhibitors of angiogenesis have been identified in bovine cartilage, and two angiogenesis inhibitors have been purified from shark cartilage. Refer to the PDQ summary on Cartilage (Bovine and Shark) for more information.
Hydrazine sulfate is a chemical that has been studied as a treatment for cancer and as a treatment for the body wasting (i.e., cachexia) associated with this disease. It has been claimed that hydrazine sulfate limits the ability of tumors to obtain glucose, which is a type of sugar used by cells to create energy. Refer to the PDQ summary on Hydrazine Sulfate for more information.
Laetrile is another name for the chemical amygdalin, which is found in the pits of many fruits and in numerous plants. Cyanide is thought to be the main anticancer component of laetrile. Laetrile has shown little anticancer activity in animal studies and no anticancer activity in human clinical trials. Refer to the PDQ summary on Laetrile/Amygdalin for more information.
Newcastle Disease Virus (NDV)
NDV is a paramyxovirus that causes Newcastle disease in a wide variety of birds (most notably, in chickens). Although NDV causes a potentially fatal, noncancerous disease (Newcastle disease) in birds, it causes only minor illness in humans. NDV appears to replicate (i.e., reproduce) substantially better in human cancer cells than it does in most normal human cells. Refer to the PDQ summary on Newcastle Disease Virus for more information.
The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
This summary was renamed from Topics in Complementary and Alternative Therapies.
Added text to state that integrative therapy combines standard care with complementary and alternative medicine practices.
Added Marijuana as a new subsection.
The St. John's wort subsection was extensively revised.
This summary is written and maintained by the PDQ Integrative, Alternative, and Complementary Therapies Editorial Board, which is editorially independent of NCI. The summary reflects an independent review of the literature and does not represent a policy statement of NCI or NIH. More information about summary policies and the role of the PDQ Editorial Boards in maintaining the PDQ summaries can be found on the About This PDQ Summary and PDQ® - NCI's Comprehensive Cancer Database pages.
Purpose of This Summary
This PDQ cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the complementary and alternative therapies found in other PDQ summaries and NCI Fact Sheets. It is intended as a resource to inform and assist clinicians who care for cancer patients. It does not provide formal guidelines or recommendations for making health care decisions.
Reviewers and Updates
This summary is reviewed regularly and updated as necessary by the PDQ Integrative, Alternative, and Complementary Therapies Editorial Board, which is editorially independent of the National Cancer Institute (NCI). The summary reflects an independent review of the literature and does not represent a policy statement of NCI or the National Institutes of Health (NIH).
Board members review recently published articles each month to determine whether an article should:
Changes to the summaries are made through a consensus process in which Board members evaluate the strength of the evidence in the published articles and determine how the article should be included in the summary.
Any comments or questions about the summary content should be submitted to Cancer.gov through the NCI website's Email Us. Do not contact the individual Board Members with questions or comments about the summaries. Board members will not respond to individual inquiries.
Levels of Evidence
Some of the reference citations in this summary are accompanied by a level-of-evidence designation. These designations are intended to help readers assess the strength of the evidence supporting the use of specific interventions or approaches. The PDQ Integrative, Alternative, and Complementary Therapies Editorial Board uses a formal evidence ranking system in developing its level-of-evidence designations.
Permission to Use This Summary
PDQ is a registered trademark. Although the content of PDQ documents can be used freely as text, it cannot be identified as an NCI PDQ cancer information summary unless it is presented in its entirety and is regularly updated. However, an author would be permitted to write a sentence such as "NCI's PDQ cancer information summary about breast cancer prevention states the risks succinctly: [include excerpt from the summary]."
The preferred citation for this PDQ summary is:
PDQ® Integrative, Alternative, and Complementary Therapies Editorial Board. PDQ Topics in Integrative, Alternative, and Complementary Therapies. Bethesda, MD: National Cancer Institute. Updated <MM/DD/YYYY>. Available at: http://www.cancer.gov/about-cancer/treatment/cam/hp/cam-topics-pdq. Accessed <MM/DD/YYYY>. [PMID: 26389506]
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Last Revised: 2016-04-21
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