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Summary statement

The term “complementary and alternative therapies” refers to a diverse group of practices and products not considered part of evidence based, conventional medicine. While complementary therapies are used together with conventional medicine, alternative therapies are used instead of conventional medicine.

Many people who have been diagnosed with cancer use complementary therapies as an adjunct to mainstream cancer treatments, usually for the management of symptoms and side-effects of treatment, and to improve quality of life. A smaller proportion of people who have been diagnosed with cancer use alternative therapies instead of conventional treatments, in an attempt to cure the disease or prevent recurrence.

The most popular complementary and alternative therapies used by people who have been diagnosed with cancer are dietary treatments (special diets, herbal remedies, megavitamins) and mind-body techniques (meditation, relaxation and spiritual healing).

There is much controversy and debate about the use of complementary and alternative therapies. This is primarily due to the substantial gap between consumer beliefs around complementary and alternative therapies, and the evidence supporting their safety and effectiveness. While there is evidence to support the use of some complementary therapies, alternative therapies are typically unproven or have been shown to be ineffective.

In some cases, use of complementary and alternative therapies can be harmful, as some therapies may interact with conventional medicines or with each other. As such, it is important that people using complementary or alternative therapies discuss this use with their medical practitioner.

Complementary and alternative medicines are a significant issue in cancer management, due to their capacity to cause harm, rapidly increasing use, availability, variety, and in some cases high financial costs.


Cancer Council Australia:

  • Supports the use of cancer treatments and symptom relief that have been scientifically tested and shown to be safe and effective.
  • Supports the right of individuals to seek information about complementary and alternative therapies, and respects their decision to use them, provided they are not at risk of being harmed.
  • Encourages people with cancer who are considering using non-conventional therapies to make an informed choice. This includes asking questions about the efficacy, risks, contraindications and cost of the therapy, and the qualifications of the practitioner.
  • Encourages people with cancer to discuss with their conventional healthcare providers (e.g. oncologist, general practitioner, care coordinator) any complementary or alternative therapies they are using or considering using, in order to minimise risk.
  • Encourages healthcare providers to routinely discuss the use of complementary and alternative therapies with all cancer patients and survivors, in an open and non-judgemental manner.
  • Calls on the Therapeutic Goods Administration to take a more active role in warning consumers about false claims made in relation to the benefits of complementary and alternative medicines.
  • Recommends that the National Health & Medical Research Council funds further scientific studies to examine the safety and efficacy of promising and commonly used complementary and alternative cancer medicines, so that people who have been diagnosed with cancer and healthcare providers can differentiate between those that are not beneficial or are dangerous, and those that may be beneficial.


Complementary and alternative therapies are a group of diverse medical and healthcare practices, products and systems not currently considered part of conventional medicine[1]. Complementary and alternative therapies used by some cancer patients and survivors include:

  • Natural/biological products including herbal medicines, vitamins and probiotics;
  • Mind and body medicine such as meditation, yoga and hypnotherapy;
  • Manipulative body-based practices including acupuncture and massage therapy;
  • Energy healing through magnet and light therapies, or practices such as qi gong and Reiki; and
  • Alternative whole medical systems such as Ayurvedic medicine, traditional Chinese medicine, homeopathy and naturopathy[1].

Complementary therapies are a range of medicines and practices used together with conventional medicine. Complementary therapies are most often used to relieve side effects of conventional cancer therapy and improve well-being, rather than being used as a cure for cancer.

Alternative therapies are a group of medicines and practices used instead of conventional medicine to treat diseases, including cancer. Many alternative therapies have not been scientifically tested, or have little evidence to support their safety and efficacy.

Conventional therapies are evidence-based treatments that have been scientifically tested, and are shown to be relatively safe and effective for treating cancer, slowing its growth or providing relief from symptoms. The main conventional treatments for cancer are surgery, radiotherapy, chemotherapy and immunotherapy. Conventional treatments are sometimes referred to as mainstream, medical or orthodox treatments.

Integrative medicine, or integrated medicine, is a term used to describe treatment that combines conventional medicine and complementary therapies for which there is reasonable evidence of safety and effectiveness.


Information on the proportion of cancer patients and survivors using complementary and alternative therapies ranges widely. Estimates of complementary therapy use in cancer patients in Australia indicate that anywhere from 17-87% have used at least one form of complementary therapy while receiving conventional cancer treatment[2][3][4][5][6]. The difference in findings may be largely accounted for by difference in study design and how complementary and alternative therapies are defined.

An international study compiling data from studies in Europe, Australasia and North America has shown that the use of complementary and alternative therapies in cancer patients has almost doubled since the 1970s. The prevalence of complementary and alternative therapies used in cancer patients increased from 25% in the 1970s and 1980s, to more than 32% in the 1990s, and to 49% after 2000[7].

In Australia, cancer patients and survivors using complementary and alternative therapies are more likely to be female, younger, and have a higher level of education[2][3][4][5][6][8]. Taking dietary supplements, making dietary changes, massage and practising meditation are the most common types of complementary and alternative therapies used in Australia by people who have been diagnosed with cancer[2][3][5][6].

A shortcoming of the literature is that the majority of studies concentrate on people receiving cancer treatment and, as such, there is a lack of information on the prevalence of conventional treatment being declined in favour of alternative therapies. Furthermore, many studies fail to distinguish between “complementary” and “alternative” therapies.

Economic impact

There is a lack of comprehensive data on the amount spent on complementary and alternative therapies by the Australian public. A 2005 survey of 1,067 Australians estimated national expenditure on 17 popular complementary and alternative therapies to be $4.1 billion annually[8].

A study of 3,015 South Australians over the age of 15 led to estimates that in 2004, the Australian public spent $1.8 billion on complementary and alternative therapies nationally[9]. This figure represented a decrease in expenditure from 2000, when a similar study estimated national annual spending to be $2.3 billion[10].

The apparent decrease in expenditure on complementary and alternative therapies between 2000 and 2004 is due to a reported decrease in the number of complementary and alternative therapies used per person and lower frequency of attendance to complementary and alternative therapy practitioners[9][10]. This reported decrease counters evidence that complementary and alternative therapy use is increasing (see above). This disparity indicates the need for further research in this area.

Reasons for use

Motivations for using complementary and alternative therapies vary widely[2]. The reasons cited most often by cancer patients and survivors for using complementary and alternative therapies include:

  • to gain an increased sense of control over treatment regimens[11][12];
  • to improve physical and emotional well-being[2][13][14];
  • to boost the immune system[2][13][15];
  • to reduce side effects of conventional treatment[2][15]; and
  • to improve quality of life[6][15].

Relatively few cancer patients and survivors use complementary and alternative medicines to directly treat cancer or to prevent it from returning[2][15].

Reasons cited by cancer patients and survivors for not using complementary and alternative therapies include the financial and time costs, fear and distrust, a lack of evidence of the efficacy of many complementary and alternative therapies, and greater satisfaction with conventional treatments[16][17].

Risks and benefits

Knowledge about the risks and benefits of many complementary and alternative therapies is limited. There is a substantial gap between consumer beliefs around complementary and alternative therapies, and the evidence supporting their safety and effectiveness.


One of the greatest risks associated with the use of complementary and alternative therapies is the possibility that people with cancer may avoid or abandon conventional treatments altogether, diminishing the prospect of remission or cure. Factors influencing the decision to refuse conventional treatment for cancer include negative doctor-patient communication experiences[18][19], desire to avoid damage or harm to the body[20], and a belief in the efficacy of complementary and alternative therapies[19].

Health claims for many complementary and alternative therapies are far in excess of the available scientific data. Similarly, information on adverse effects and interactions with conventional medicines is often lacking. In one Australian study 92% of users thought complementary and alternative therapy was completely safe[6]. However, some complementary and alternative therapies may have harmful side effects both independently and in relation to use with conventional cancer treatments. The quality and safety of some complementary and alternative medicines cannot be guaranteed, as these preparations are not subjected to the evaluation process that conventional pharmaceuticals undergo. Furthermore, as complementary and alternative medicine practitioners are not regulated and educational standards highly variable, people with cancer are at potential risk of injury from unqualified practitioners[21].

There is potential for drug interactions between biologically active complementary medicines, such as supplements and herbs, and conventional therapies such as chemotherapy[22]. While some studies report a beneficial effect of antioxidants as a complementary therapy for cancer, there is evidence to suggest they may decrease the efficacy of radiotherapy[23].

Many complementary and alternative therapies are promoted as being 'natural' and thus safe. The belief that natural equates to safe is a misconception which can create the potential for harm. It is important that users understand that a natural therapy is not necessarily harmless when used either alone or with other medicines.

The potential of harm arising from the use of complementary and alternative medicines demonstrates the importance of open discussion between patients and healthcare providers, yet fewer than 50% of cancer patients using non-conventional treatments discuss their use with their conventional healthcare providers[6].


Users have reported both psychological and physical benefits associated with complementary and alternative therapies[5][24].

One Australian study found 90% of cancer patients using complementary and alternative therapies reported perceived benefits, with the most common benefits being improved quality of life, and reduced symptoms and side effects[5].

Another Australian study found that complementary and alternative therapy use among cancer patients and survivors reduced stress and depression levels, but did not affect health-related quality of life overall. Direct comparisons in relation to stress and depression are difficult; complementary and alternative therapy users reported significantly higher stress pre-cancer compared to non-users, suggesting this group may be more psychologically vulnerable, with complementary and alternative therapy acting as an effective psychological intervention[24].

Evidence for some specific complementary therapies is growing. For example, studies comparing published randomised trials suggest acupuncture is effective in reducing chemotherapy-induced vomiting (but not nausea)[25]. Relaxation therapy has been shown to reduce the frequency and severity of hot flushes in people undergoing breast cancer treatment[26]. Also, analysis of various psychosocial interventions has shown some effectiveness in reducing pain in cancer patients[27].


In 2004 about half of complementary and alternative therapy users surveyed reported that they assumed these therapies were independently tested by a government agency, for either safety, efficacy or to validate product claims. However, despite being regulated by the Therapeutic Goods Administration (TGA), the majority of complementary and alternative therapies are not tested for efficacy by the agency[9]. The TGA does ensure that labelled products contain “relatively safe” ingredients and are manufactured to a minimum standard. By comparison, evidence for conventional medicines is evaluated by the TGA for safety, quality and efficacy.

In 2012, the TGA began a series of reforms for the regulation of complementary medicines. The reforms aim to enhance the regulatory framework around complementary medicines and strengthening its integrity and transparency. The new framework aims to improve community understanding of regulatory procedures for complementary and alternative therapies and the TGA’s role in this process.

Questions to ask

The World Health Organization recommends that consumers use the following checklist to help facilitate informed use of complementary and alternative therapies[28].

  • Is the therapy suitable for treating the condition?
  • Does the therapy have the potential to prevent, alleviate and/or cure symptoms or in other ways contribute to improved health and well-being?
  • Is the therapy or herbal medicine provided by a qualified (preferably registered and certified) practitioner with adequate training background, good skills and knowledge?
  • Are the products or materials of assured quality, and what are the contraindications and precautions?
  • Are the therapies or herbal medicinal products available at a competitive price?


Understanding Complementary Therapies
Cancer Council publication with cancer-specific information on specific complementary therapies

Memorial Sloan-Kettering Cancer Center
Evidence based information on a wide range of specific complementary and alternative therapies

Office of Complementary Medicines, Therapeutic Goods Administration
Regulatory information on complementary and alternative therapies in Australia

CAM on PubMed
Database for complementary and alternative therapies research

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