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Patient education: Complementary and alternative medicine treatments (CAM) for cancer (Beyond the Basics)

Edzard Ernst, MD, PhD, FMEdSci, FSB, FRCP, FRCP (Edin.)
Section Editor
Reed E Drews, MD
Deputy Editor
Diane MF Savarese, MD
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Complementary and alternative medicine (CAM) is defined by the National Center for Complementary and Alternative Medicine as "a group of diverse medical and healthcare systems, practices, and products that are not presently considered to be part of conventional medicine" [1]. For some CAM practices, there is scientific evidence that a treatment is both beneficial and safe. For many other practices, evidence is negative, lacking, or inconclusive.

A large percentage of people with cancer use some form of CAM. Most patients who use CAM are not dissatisfied with conventional medicine but find that CAM treatments appeal to their values and beliefs about health and life. Being diagnosed with cancer and undergoing treatment is a frightening, exhausting, and demanding experience. CAM appeals to many patients with cancer because these treatments often offer a chance to take control, feel better, and decrease uncomfortable symptoms, such as pain, fatigue, and nausea.

Placebo effect — The concept of a placebo effect is important to understand when trying to evaluate the benefit of interventions for cancer and cancer treatment-related symptoms. A placebo is an inactive medication or treatment. Well-designed comparative studies include a placebo treatment, as well as a "real" treatment, so that the two may be compared. For example, a CAM treatment that claims to improve symptoms of nausea in 50 percent of patients is of little benefit if the placebo treatment also improves symptoms in 50 percent of patients.

The placebo effect is not well understood but has a strong influence on the results of any research study, whether in conventional or complementary medicine.


Complementary medicine is a treatment, practice, or product that is used alongside conventional medical treatment. It is not meant to replace conventional cancer treatment but is available to alleviate side effects or improve a patient's sense of well-being.

Alternative medical systems — Alternative medical systems are healing techniques and beliefs that have developed over time and include homeopathy, naturopathy, and traditional Chinese medicine (which includes acupuncture).

Acupuncture — Acupuncture involves inserting thin metal needles into the skin at specific points on the body. It causes little to no pain. Electrical stimulation is sometimes applied to the acupuncture needle. There have been numerous studies of acupuncture's efficacy in reducing nausea, pain, dry mouth after radiation treatment for head and neck cancer, and hot flashes, and results have been mixed.

Acupuncture with electrical stimulation has been found to be useful in treating nausea and vomiting from chemotherapy.

Some trials suggest that acupuncture can reduce cancer pain, although a review of multiple trials showed it to be of no benefit.

In one trial, the use of acupuncture significantly reduced mouth pain and the sensation of dry mouth in a group of patients undergoing radiation therapy for head and neck cancer.

Traditional Chinese medicine — Other forms of traditional Chinese medicine, which use standard combinations of herbs or botanicals for various illnesses, are difficult to study. Chinese herbal medicines are widely used in many areas of Asia to reduce the toxicity associated with conventional anticancer therapy; however, little information is available from controlled studies regarding the safety and efficacy.

Mind-body techniques — Mind-body techniques include practices such as hypnosis, guided imagery, meditation, yoga, biofeedback, and prayer. These techniques may be useful before or during painful or stress-inducing medical procedures, chemotherapy, or radiation treatment to control anxiety, pain, or nausea and vomiting. Patients of any age can learn mind-body techniques.

Hypnotherapy — Hypnosis is a state of altered consciousness that allows you to focus away from your pain, anxiety, or nausea. You are not sleeping while hypnotized but are actually in a state of heightened imagination, similar to daydreaming. An expert can hypnotize an individual, or you can learn self-hypnosis techniques. Hypnosis is safe and has few side effects.

It is not clear how or if hypnosis is helpful, although studies have suggested that it may be useful for controlling pain and nausea/vomiting in various settings and may reduce vomiting that can develop before starting chemotherapy (called anticipatory emesis).

One study examined the benefit of hypnosis before surgery for breast cancer [2]. They found that women who had a 15-minute hypnosis session before surgery had less pain, nausea, and fatigue after surgery, and they required significantly less time in the operating room compared with women who were not hypnotized. It is not clear whether some of these benefits represent placebo effects.

Hypnosis may also be useful in children for preventing anxiety and pain from difficult procedures, such as lumbar puncture (spinal tap) or bone marrow biopsy.

Visual or guided imagery — Visual or guided imagery is a technique that encourages the patient to relax by focusing on calming thoughts or experiences. You sit or lie in a comfortable position while imagining a pleasant experience, such as relaxing on the beach. In one study, women receiving chemotherapy for newly diagnosed breast cancer had a better quality of life if they used relaxation training and guided imagery, as compared with a group that had chemotherapy alone [3].

Spirituality — A majority of individuals have religious beliefs, and many people rely on their religion or spirituality in difficult times, such as during treatments for cancer [4]. Researchers found that spirituality, when combined with conventional medicine, was an important component in the healing process and was of benefit not only to the patient but also to caregivers and healthcare professionals [5].

Some, but not all, studies have shown that religious involvement and spirituality are associated with better health outcomes, including longer life, improved coping skills, better health in general, and lower rates of anxiety, depression, and suicide [6].

Body-based therapies — Body-based therapies use movement or manipulation of one or more parts of the body.

Massage therapy — Massage involves stroking and kneading the skin, muscles, and connective tissues. There are several types of massage therapy.

Classic or Swedish massage is aimed primarily at muscles. It reduces tension and increases blood flow.

Reflexology is massage of the hands and feet based on a system of points that are claimed to correlate to other areas of the body.

Chair massage is done while the patient sits fully clothed in a special chair that slopes forward, allowing the therapist access to the back, neck, and shoulders.

Deep tissue massage is a form of intense tissue manipulation.

A study was done in 1290 cancer patients who received massage therapy at Memorial Sloan-Kettering Cancer Center. It found that pain, anxiety, fatigue, and nausea decreased by 50 percent in patients who received massage. Some patients reported benefits lasting up to 48 hours [7]. A small number of insurance companies cover massage therapy as a complementary cancer treatment.

Energy therapies — Energy therapies involve using assumed energy fields to heal and maintain wellness. Believers in energy medicine describe disruptions in the energy field as a cause for illness and teach that balancing energy can aid in healing. It is difficult to study the effectiveness of energy medicine due to the intangible nature of the body's "energy."

Reiki is a form of energy medicine and has been evaluated in several clinical trials for treatment of anxiety and improvement of well-being in cancer patients. Some, but not all, trials showed positive results, although the studies showing benefit were not well designed, and it is difficult to distinguish the true benefit from placebo effect.


Alternative cancer treatments (ACTs) are usually promoted as replacements to conventional cancer treatments. Cancer patients may seek them out in the hope of a cure. Some ACTs require the patient to receive treatment at their clinics, often located outside the United States. In many cases, reliable clinical trials have found these treatments ineffective or unsafe, and the US Food and Drug Administration (FDA) has not given approval for these treatments inside the United States.

Dietary ACTs — Good nutrition is important for cancer patients. However, none of the dietary ACTs are proven to prolong life or cure cancer. In addition, some alternative cancer diet treatments are costly and potentially harmful.

Gerson regimen — The Gerson regimen requires an organic, vegetarian diet and includes a strict schedule for ingesting juice made from fruits and vegetables. In addition, patients are given a number of vitamin supplements. No clinical study has proven this regimen's efficacy. It is not recommended and may be expensive and harmful.

Macrobiotic diets — Macrobiotic diets are low-fat, vegetarian diets that include large amounts of complex carbohydrates. One report found that one-third of cancer patients who followed a macrobiotic diet lost weight, which resulted in other problems [8]. This was likely due to several factors, including the expense or inaccessibility of some of the required foods, time spent preparing the meals, and the restrictive, sometimes unpleasant, nature of the diet. Macrobiotic diets are not recommended for people with cancer.

Selected vegetables — Selected vegetables (SV), also called Sun's Soup, is a blended, boiled, and freeze-dried product that claims to have immune-stimulatory and anticancer properties. Two small studies have been conducted in patients with late-stage non-small cell lung cancer, both of which found that patients who received the supplement had an improved survival. Patients in both studies received conventional medical treatments, as well as the SV mix. However, the studies were small and had weaknesses in study design; further studies are needed before the treatment can be considered safe and effective.

Herbal medicine — Combinations of herbs (also called botanicals) are often promoted as ACTs. Herbal medicines may come in the form of a powder, liquid, or pill. Examples of herbal treatments include essiac, ginseng, green tea, Flor Essence tea, mistletoe, PC-SPES (a mixture of herbs marketed for prostate cancer, now recalled due to an increased risk of blood clots), sho-saik-to, and St. John's wort [9].

None of these herbals have been proven to cure or improve cancer in reliable clinical studies; some can cause dangerous side effects. In addition, some herbal products (particularly St. John's wort) can interact with conventional cancer treatments, making conventional treatments less effective [9].

Other supplements — A number of dietary supplements have been advertised as being useful ACTs. These include coenzyme Q10, hydrazine, melatonin, shark cartilage, shiitake mushroom extract, and thymus extract. No supplement has proven reliable as either an alternative or complement to conventional cancer treatment [9]. Supplements and herbal medicines you can buy without a prescription can be expensive, and sometimes they are found to contain unsafe ingredients. Be skeptical of any product that claims to be a "miracle pill" or says it cures cancer or any other serious disease. Talk to your doctor before you spend money on these treatments.


General recommendations — Anyone who is considering use of a complementary, alternative, or conventional medical treatment should gather information about the safety, risks, and benefits of the treatment. Reliable information sources include the healthcare team (clinician, nurse, dietitian) and government-sponsored websites.

It is important to choose the person providing CAM with care; you should inquire about education and licensing requirements since these vary by state. The safety of CAM treatments should be considered. Being "natural" does not mean that a product or treatment is safe.

The cost of a CAM treatment must also be considered as these treatments are generally not covered by commercial or government-funded health insurance. A patient or family who uses its life's savings for an unproven "cure" is likely to be disappointed.

Questions to consider — When evaluating an alternative or complementary treatment, consider the following questions:

Does the treatment require patients to stop conventional medical care?

Does it claim to cure cancer?

Is it offered by only one individual or by an established, recognized cancer treatment facility?

Is it a secret that only certain people can share?

Does it require travel to another country? Is it approved in the United States?

Is it based on well-controlled, scientific research?

Is it expensive?

Is the group or person promoting the CAM treatment an expert in cancer treatment?

Do the promoters attack the scientific and medical research community?

Combining CAM and conventional treatments — Patients who are considering a CAM treatment must consider the safety and potential benefit of the treatment itself and must also consider how the CAM treatment could interact with conventional treatments, such as chemotherapy.

It is possible for a CAM treatment, especially a dietary alternative cancer treatment (ACT), herbal medicine, or other supplement, to alter the body's metabolism and clearance of chemotherapy in unexpected ways. Because CAM treatments are not generally tested for use in combination with standard chemotherapy, they could interfere with the beneficial effect of the chemotherapy or potentially increase the risk of toxic side effects.

Refusing or delaying conventional treatments — Patients should be very careful about refusing or delaying conventional treatment in order to receive CAM treatment instead. A recent study showed that women with breast cancer who refused or delayed surgery in favor of CAM were much more likely to have cancer progression and to die of their disease than they would have been had they undergone immediate surgery. Similarly, women who did not follow through with hormone therapy, chemotherapy, or radiation as directed were much more likely to have cancer progression or die of cancer than they would have been had they undergone the recommended treatment [10].


Your healthcare provider is the best source of information for questions and concerns related to your medical problem.

This article will be updated as needed on our website (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.

Patient level information — UpToDate offers two types of patient education materials.

The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: Managing pain when you have cancer (The Basics)
Patient education: Nausea and vomiting with cancer treatment (The Basics)
Patient education: Alternative medicine (The Basics)
Patient education: Probiotics (The Basics)

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.

This topic currently has no corresponding Beyond the Basics content.

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.

Investigational agents for asthma
Clinical use of echinacea
Clinical use of ginkgo biloba
Clinical use of saw palmetto
Clinical use of St. John's wort
Complementary and alternative remedies for rheumatic disorders
Complementary and alternative therapies for cancer
Hepatotoxicity due to herbal medications and dietary supplements
Menopausal hot flashes
Nephropathy induced by aristolochic acid (AA) containing herbs
Overview of herbal medicine and dietary supplements

The following organizations also provide reliable health information.

National Cancer Institute


National Center for Complementary and Integrative Health

Natural Medicines

Memorial Sloan-Kettering Cancer Center

American Society of Clinical Oncology


Literature review current through: Nov 2017. | This topic last updated: Fri Apr 28 00:00:00 GMT+00:00 2017.
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