Complementary and alternative medicine (CAM) includes a variety of therapeutic approaches not typically taught in conventional medical schools or used by the majority of conventionally trained physicians (Gordon JS, Curtin SR, Comprehensive cancer care: integrating alternative, complementary, and conventional therapies. Perseus, Cambridge, MA, 2000). Complementary refers to modalities used to complement—that is, used in addition to conventional medicine—while alternative is usually used to describe treatments intended to replace conventional treatment (Murphy et al., Informed decisions: the complete book of cancer diagnosis, treatment, and recovery. Viking, New York, 1997). Some such practices enjoy a history of research to support claims of efficacy but have not gained popularity among the majority of medical practitioners (e.g., use of acupuncture to reduce chemotherapy-induced nausea) (Dibble et al., Oncol Nurs Forum 27:41-47, 2000; Mayer, Annu Rev Med 51:49-63, 2000; Shen et al., JAMA 284:2755-2761, 2000); others either lack or have unsupportive research to back claims of safety or efficacy. Even so, the determination of which modalities are complementary or alternative may shift over time as research and practice move some into conventional use and disprove others. Some practices less amenable to our current research epistemology may never move out of CAM nomenclature or perceptions (such as multimodality system approaches, energy medicine, or spiritually based practices).
Currently, CAM broadly encompasses a range of substances, practices, practitioners, and belief systems that fall outside of the conventional medical model. CAM substances include botanicals (also known as herbs), vitamins, minerals, specific nutrients, enzymes, foods, and homeopathy. CAM practices include a variety of mind-body and meditative movement (e.g., meditation, yoga, Qigong; Larkey et al., 2010) interventions, dietary modifications such as macrobiotic or raw food, and numerous culturally based interventions focusing on various body, mind, or spiritual interventions. CAM practitioners use therapeutics with varying levels of training, with great variation in licensing laws and insurance reimbursement depending on state (United States), province (Canada), or country (Cherkin et al., J Am Board Fam Pract 15:378-390, 2002; Eisenberg et al., Ann Intern Med 137:965-973, 2002). These practitioners include, but are not limited to, naturopathic physicians, chiropractors, acupuncturists, herbalists (both Western and Chinese), massage therapists, Ayurvedic practitioners, Native American healers, Tibetan physicians, Reiki practitioners, Healing Touch practitioners, and spiritual healers. Although conventional in many cultures, belief systems or perceptions of health, healing, and the body that are considered to be CAM by conventional medical practitioners in the United States (USA) include traditional Chinese medicine (TCM), Ayurvedic medicine, Tibetan medicine, and Native American medicine. CAM substances, practitioners, practices, and belief systems have undergone varying levels of scientific scrutiny, with the current emphasis in US research focusing on elucidating their biological mechanisms of action.
The US National Center for Complementary and Alternative Medicine (NCCAM) at the National Institutes of Health (NIH) categorizes CAM into four domains ( http://nccam.nih.gov/health/whatiscam ): mind-body medicine, such as meditation, prayer, and music therapy; biologically based agents, such as dietary supplements, herbal products, and functional foods; manipulative and body-based practices, such as chiropractic manipulation and massage; and energy medicine, which includes biofield therapies (i.e., Qigong, Reiki, and Therapeutic Touch) and bioelectromagnetic-based therapies (pulsed fields and magnetic fields). In addition, NCCAM studies whole medical systems, which cut across all domains, including naturopathic medicine, TCM, and Ayurveda.
This chapter begins by discussing how CAM therapies currently fit into the field of cancer prevention research and then discusses some of the more promising CAM biological agents being studied for their cancer prevention properties, including foods, spices, and botanicals. The research on these biological modalities most resembles conventional research on mechanisms of action, such as chemoprevention or dietary interventions that effect biochemical changes. Next, this chapter discusses some of the CAM approaches that are less well matched to the medical model of biochemical responses, including healing approaches that utilize the mind-body relationship, traditional systems of healing founded in ancient wisdom and practice, and the more esoteric areas of spirituality and energy medicine.