POOR DISCLOSURE

Although the use of complementary medicines (CMs) is popular among people with cancer, many do not inform their medical doctors that they are using it. This may be because they anticipate disinterest or a negative response or think doctors are unable or unwilling to contribute meaningful information, or because it is perceived as irrelevant to the biomedical treatment course (Adler & Fosket 1999). It is therefore not unusual for patients to be receiving treatment and advice from a variety of practitioners without a central healthcare provider coordinating and supervising care.

Lack of disclosure can give rise to serious problems such as drug interactions and failure to recognise CM-induced adverse effects and withdrawal effects. In oncology, this can have far-reaching consequences. Open and honest communication about CM should be the standard for both patients and clinicians in order to avoid or minimise adverse events and provide an opportunity for patients to express their personal preferences for treatment.

BENEFITS OF CM IN ONCOLOGY

A growing number of CM therapies are being subjected to clinical trials to determine their effectiveness and role in cancer treatment. In most instances, CM therapies are being investigated for symptom relief and improvements in quality of life.

A review in the European Journal of Cancer illustrates that the weight of evidence to support the use of some complementary approaches in cancer is clearly positive or showing a positive trend (Ernst 2003). According to the review, positive evidence exists for Allium spp vegetables (e.g. onions), detoxification, Sho-saiko-to, St John’s wort, acupuncture and relaxation, while there is positive trend for green tea, phyto-oestrogens, Gerson diet, Aloe vera, melatonin, support group therapy, hypnotherapy, therapeutic touch and enzyme supplements.

Evidence is well established for psychosocial therapies in cancer management, such as hypnosis, music therapy, meditation and stress management, and for acupuncture (Cassileth 1999). For example, there is evidence from randomised trials supporting the value of hypnosis for cancer pain and nausea; relaxation therapy, music therapy and massage for anxiety; and acupuncture for nausea (Vickers & Cassileth 2001). Studies involving people with cancer or cancer survivors report benefits of yoga for stress, anxiety, insomnia and cancer-related symptoms and show it increases quality of life (Bower et al 2005, Cohen et al 2004).

Results from clinical studies and/or experimental models indicate that several other therapies have the potential to reduce drug-induced side effects and toxicities. For example, a Cochrane systematic review that analysed the results of four trials using a Chinese decoction containing the herb astragalus (huang-qi) as an adjunct to chemotherapy concluded that co-administration of the herbal treatment with chemotherapy produced a significant reduction in nausea and vomiting and a decrease in the rate of leucopenia (Taixiang et al 2005). The review also stated that no evidence of harm was identified with use. The herbs ginger and baical skullcap have been found to reduce symptoms of cisplatin-induced nausea in experimental models (Aung et al 2003, Sharma & Gupta 1998, Sharma et al 1997), and animal and human studies suggest long-term carnitine administration may reduce cardiotoxic side effects of adriamycin (Mijares & Lopez 2001, Waldner et al 2006). Additionally, preclinical and clinical studies suggest that anthracycline-induced cardiotoxicity can be prevented by administering coenzyme Q10 during cancer chemotherapy that includes drugs such as doxorubicin and daunorubicin. Studies further suggest that coenzyme Q10 does not interfere with the antineoplastic action of anthracyclines and might even enhance their anticancer effects (Conklin 2005). Many other natural substances such as St Mary’s thistle, grapeseed extract, St John’s wort, parthenolide (from feverfew) and curcumin show promise in preliminary studies in reducing chemotherapy-induced organ toxicity or other associated adverse effects and are discussed in individual monographs in this book. Research has also been conducted with individual antioxidant vitamins and minerals.

A comprehensive model of cancer care requires that patients take an active role in their healthcare and find partners to work with them during the process. Medical practitioners play a key role; however, many other healthcare providers can augment their work and help provide patients with holistic care. A number of complementary therapies have proven benefits and are considered safe. These should be made available to patients to increase their sense of wellbeing and improve their quality of life and experience of cancer, its treatments and recovery.

SUPPORTIVE MEASURES

Supportive care is care that helps patients and their families cope with cancer and its treatment, starting from pre-diagnosis, through the process of diagnosis and treatment, to cure, continuing illness or death, and into bereavement. It helps the patient to maximise the benefits of treatment and to live as well as possible with the effects of the disease.

A number of CM therapies and treatments can provide substantial support to people with cancer by providing symptomatic relief, enhanced quality of life and improved sense of wellbeing, without causing harm. They also have important benefits in addition to those derived from their inherent therapeutic effect:

The information in Table 10.1 (pp 130–31) is a guide to some of the better known and researched therapies and treatments that may provide supportive benefits for patients. To promote appropriate and safe use, each individual’s characteristics, medication use, general health and overall situation needs to be assessed. Where herbal and nutritional medicines are mentioned, healthcare providers should check for potential interactions with drug therapy.

TABLE 10.1 CM Therapies Used to Support Cancer Patients

CM TO IMPROVE SURVIVAL

Although CM is most often used to treat symptoms and enhance wellbeing, to a lesser extent it is being used as a potential cure for cancer. Examples of some CM treatments that have been used by patients to cure cancer are listed in Tables 10.2 (p 131) and 10.3 (p 132). Some of the listed treatments are currently under investigation and have been subject to in vitro and in vivo studies, whereas other treatments, such as Hoxsey therapy, the Di Bella regimen, shark cartilage and laetrile, are generally considered ineffective. A full review of the available evidence is beyond the scope of this chapter, but further information can be found in the relevant monographs. (Updated information is available at some of the websites listed in Table 10.5, pp 144–5.)

TABLE 10.2 Complementary Medicines That have been Used to Improve Cancer Cure Rates

TABLE 10.3 CM Therapies That have been Used to Improve Cancer Cure Rates

It is interesting to note that approximately two-thirds of commercially available anticancer drugs are derived from or related to natural products, including enzymes, hormones, plants and fungal extracts (Bryant et al 2003). For example, an extract of wild chervil was mentioned in an ancient medical text as a useful salve against tumours, and it is now known that podophyllotoxin, a cytotoxic agent, is present in the Podophyllum species of plants. The most recent anticancer products are the taxanes (paclitaxel and docetaxel), which are derived from the yew tree Taxus baccata, and the camptothecins (topotecan and irinotecan) from Camptotheca accuminata.

WHOLE SYSTEMS RESEARCH (WSR)

Cancer care is currently developing into a complicated network of interventions that are delivered at different times and places with different intentions. Some interventions are offered by healthcare professionals at an oncology centre; others are offered by CM practitioners; still others, such as special diets, meditation and OTC natural supplements, form part of a patient’s individualised package of self-care. These treatment interventions are influenced by psychosocial factors such as the nature of the patient–provider relationship, varying levels of social support, and an individual patient’s personality. Ultimately, a patient’s outcomes are a result of all components of care, and it is likely that the effect of the whole is greater than the sum of its parts (Verhoef et al 2005).

As a result, there is a need to consider whether the current research approaches in clinical cancer care adequately cover the ongoing treatment choices and combinations. One approach developed by CM researchers is whole systems research (WSR), which is proposed as an additional research method for modern systems of care, whether they include complementary medicine or not.

WSR focuses on the multidisciplinary approach taken by patients, rather than adopting a reductionist perspective where all variables remain constant except one that is altered. WSR also focuses more on the individual patient and less on group-averaged results, under the assumption that there will be patient heterogeneity in response and that important information about the healing approach in that heterogeneity may otherwise be missed (Verhoef et al 2005). Integral to WSR is the belief that clinical research should reflect real-world practice and then be used to inform future clinical practice. A mixed-methods approach that holds qualitative and quantitative research methods in equal esteem and captures information about different domains is advocated, because whole systems are complex and no single method can adequately capture the meaning, process and outcomes of these interventions (Verhoef et al 2005).

In summary, WSR is research that:

OUTCOMES RESEARCH

Researchers in Canada have determined nine outcome domains relevant to WSR (Fonnebo et al 2007), as follows: physical, psychological, social, spiritual, quality-of-life, holistic, individualised, process and context outcomes. At the same time, validated outcome instruments have been identified to measure these domains as well as gaps where no adequate measures currently exist. Researchers in the UK and at the University of Arizona, USA, have led the way by conceptualising and developing these instruments, some examples of which are Measure Yourself Medical Outcome Profile, Measure Yourself Concerns and Wellbeing, the Patient Enablement Questionnaire, and the Consultation and Relational Empathy Measure (Fonnebo et al 2007).

EXPLORING EXCEPTIONAL PATIENTS

Becoming familiar with patients’ individual experiences and collating information to find common themes is one method of identifying therapeutic approaches that show promising results and warrant further clinical research. In a way, this method of data collection is much like the practice of traditional healers of old, who were required to develop excellent observational and history-taking skills to learn more about the benefits and risks of treatments being applied.

This realisation has led to several international initiatives to collect and systematically categorise and review histories of patients who experience an unexpected benefit or spontaneous remission after CM treatments. Several research groups in different countries have initiated studies in this area, either collecting histories from the treatment providers or recruiting case histories mainly from patients themselves (Launso et al 2006). The US National Cancer Institute concentrates on a series of what they designate as ‘best cases’, whereas in Norway the National Research Centre in Complementary and Alternative Medicine (NAFKAM) includes both ‘best’ and ‘worst’ cases in its reviews.

LIMITED FUNDING

Despite the enormous popularity of CM, relatively little research has been conducted into the efficacy and safety of its use by people with cancer compared to similar research into conventional medicine. Currently, the majority of research into CM has been conducted in the USA, where a significant effort has been made, with government funding. In 1998 the Office of Cancer Complementary and Alternative Medicine (OCCAM) was established within the National Cancer Institute (NCI) in the United States to coordinate and enhance activities of the NCI in CAM research as it relates to the prevention, diagnosis and treatment of cancer, cancer-related symptoms and side effects of conventional cancer treatments (see http://www.cancer.gov/). Since the establishment of OCCAM, the NCI’s research expenditure for CAM has more than quadrupled, from approximately US$28 million for the financial year (FY) 1998 to approximately US$129 million in FY 2004.

In the UK, the National Cancer Research Institute has a complementary therapies clinical studies development group, which is looking at prioritising areas for study and methodological issues. In Australia and New Zealand there is still relatively little government funding for research in this area; however, the establishment of the National Institute of Complementary Medicine (NICM) in 2007 is an important step towards increasing awareness of this need and lobbying government and philanthropic organisations.

ADVERSE REACTIONS

Type A and type B adverse reactions are possible with all therapeutic agents, including complementary medicines (see Chapters 7 and 8). Type A effects are the most common and predictable because they are dose-related, generally of mild to moderate intensity, and reversible. Regarding vitamins, minerals and the cancer patient, toxicity concerns mainly relate to vitamin A and the minerals selenium and zinc.

INTERACTIONS

Cytotoxic anticancer drugs are among the strongest drugs available and tend to have a complex pharmacological profile, narrow therapeutic index, steep dose–toxicity curve and many pharmacokinetic and pharmacodynamic differences both within and between patients (Beijnen & Schellens 2004). Often combinations of medicines are used to address the cancer itself, reduce the associated drug toxicities and provide palliation and symptom relief. As such, polypharmacy is standard practice. Additionally, many cancer patients are elderly and may be taking medicines for comorbid conditions such as cardiovascular disease, and as the number of concomitant medicines increases, so too does the risk of interactions (Blower et al 2005). Age-related changes to renal and hepatic functions and reduced homeostatic reserve are other complicating factors that make the prediction and avoidance of interactions difficult in this population.

As discussed in Chapter 8, there are two main categories of interaction, pharmacodynamic and pharmacokinetic, and a minor category known as physicochemical: