A recent article published in the Journal of the National Cancer Institute reviewed CAM therapies and evaluation criteria guidelines suggested by several researchers for complementary and alternative medicine (CAM).
CAM use by cancer patients has steadily increased throughout the past ten years. While research on CAM has also begun to increase, little is known about the safety and efficacy of most CAM therapies. This creates a dilemma for physicians, who have difficulty acquiring authoritative information on CAM. Several leading researchers recommending guidelines for evaluating CAM were interviewed in this article.
Researchers at the Osher Institute of Harvard Medical School in Boston recently published a review of CAM therapies in the December 3rd, 2003
Annals of Internal Medicine. This team summarized the scientific evidence on a wide array of CAM most commonly used by cancer patients, focusing on the safety (based on side effects or interactions with other drugs/treatments) and/or effectiveness of individual CAM therapies. As a result, CAM treatments were classified in one of three categories: reasonably recommended, accepted (with some caveats) or discouraged. Overall, more CAM therapies appear to alleviate symptoms, of cancer or cancer treatment, than to treat cancer itself. The only therapy the authors tentatively recommended as a potential treatment for cancer was Vitamin E for latent prostate cancer.
The Osher Institute researchers advised physicians to accept, monitor and consider recommending vitamin use for some patients. They do not discourage a CAM therapy unless there are major safety concerns or two or more randomized clinical trials have been performed, two-thirds of which suggest the therapy does not work. However, they note that certain subpopulations of patients may be at increased risk from a CAM therapy. Examples include deep massage and acupuncture for patients with higher risk of bleeding and the use of antioxidants for patients undergoing chemotherapy and radiation treatment. Theoretically, antioxidants may block the cancer-killing effects of chemotherapy or radiation treatments because the free radicals generated by these conventional therapies are partially responsible for their anticancer effects. A few studies have reviewed this issue, but have produced mixed results.
Barrie Cassileth, Ph.D., chief of the Integrative Medicine Service at Memorial Sloan-Kettering Cancer Center (MSKCC) in New York and author of The Alternative Medicine Handbook, reports that 8% to 10% of cancer patients utilize CAM treatments prior to, or instead of, conventional treatment. This delay may result in a cancer with good prognosis developing into a more widespread and higher grade cancer. Cassileth is also concerned about adulteration, misbranding and lack of regulation of dietary supplements available in the United States. MSKCC does not use dietary supplements available in U.S. health food stores for its clinical trials. They import Japanese supplements, which are regulated as drugs, or raw substances from China which undergo testing for contamination, consistency and stability.
Andrew Vickers, Ph.D., a research methodologist and biostatistician at MSKCC Integrative Medicine Service and author of several articles on CAM, recommends that physicians discourage the use of CAM therapies that are unproven and have high risk of adverse side effects or interactions. He also advises against treatments that are used instead of conventional treatment (rather than those which can be used in addition to it) or that require travel or financial cost. He suggests that physical, economic and emotional harm may result from extreme measures such as traveling to Mexico in the last weeks of life for an unproven therapy.
The following CAM therapies were included in the Annals of Internal Medicine review article authored by the Osher Institute. They “may be reasonably accepted and, in some cases, considered for recommendation”:
- Certain dietary regimens
- Vitamin E supplementation
- Soy supplementation in prostate cancer
- Selected herbal products and biological agents
- Acupuncture for chemotherapy-related nausea/vomiting or for pain
- Massage for anxiety or pain
- Moderate exercise
- Psychological/mind-body therapies (e.g., support groups, relaxation training, imagery)
The same authors suggest that these CAM therapies should be avoided:
- Highly restrictive dietary regiments for those with poor nutritional status
- Antioxidants for those receiving concurrent radiation or chemotherapy
- Supplements with anticoagulant effects for those who are thrombocytopenic (low platelet levels), receiving anticoagulant therapy, or undergoing surgery
- Phytoestrogens (e.g., soy supplements) for patients with breast cancer (especially those who have estrogen receptor-positive tumors or are taking tamoxifen) or endometrial Cancer
- Acupuncture for those who are thrombocytopenic or receiving anticoagulant therapy
- Deep tissue or forceful massage for those who are thryombocytopenic or receiving anticoagulant therapy
- St. John’s wort for those undergoing concurrent chemotherapy or taking other drugs for which failure to achieve therapeutic levels could lead to serious consequences
- High-dose vitamin A is prudent for all patients to avoid
- High-dose Vitamin C is prudent for all patients to avoid
Each of the CAM researchers interviewed reported increased usage of CAM among cancer patients and called for research on the safety and effectiveness of CAM therapies. Additionally, databases that collect and summarize available research on individual CAM therapies are needed to provide physicians and patients with the most current, reliable information.
References: Reynolds, T. Keeping up with alternative medicine: researchers offer evaluation criteria.
Journal of the National Cancer Institute. 2003;95:96-98.
Weiger WA, Smith M, Boon H, et al. Advising patients who seek complementary and alternative medical therapies for cancer.
Annals of Internal Medicine. 2002;137:889-903.