BOSTONAlthough some see complementary and alternative medicine (CAM) therapies as lying outside the mainstream clinical setting, Charles Loprinzi MD, of the Mayo Clinic College of Medicine, reviewed 27 CAM trials done in traditional clinical settings, some complete, some in process. These studies are well-designed, adequately powered, are accruing large numbers of patients, and are being published in peer-reviewed medical journals, Dr. Loprinzi said at the Society for Integrative Oncology Third International Conference.
These trials done by the Mayo Clinic, often in conjunction with the North Central Cancer Treatment Group, began in the late 1970s. Their earliest work involved trying to find ways of alleviating some of the adverse symptoms associated with cancer treatments, including mucositis. A randomized trial of 95 patients showed that patients who put ice chips in their mouth for 30 minutes during chemotherapy had significantly less severe ulcerations and a 50% reduction in the number of days of mucositis, compared with a control group. However, a double-blind placebo-controlled trial involving 164 patients found no difference in mucositis between patients who used chamomile or placebo mouthwash.
Another symptom studied by the Mayo group is skin inflammation, such as pain, infection, and scarring, caused by radiotherapy. Aloe vera, an extract from a cactus plant, has been promoted as an agent for treating burns and other skin irritations. A placebo-controlled, double-blind trial of 194 breast cancer patients scheduled to have radiation therapy to the chest, found no difference in the severity of the dermatitis or its duration between the women who received aloe vera gel vs placebo gel.
Dr. Loprinzi reported that randomized trials have failed to show a benefit for vitamin E, soy, black cohosh, or acupuncture to prevent hot flashes. The jury is still out on one nutritional supplement DHEA (dehydroepiandrosterone), an androgen that is converted to testosterone in the body. A pilot study with 22 patients found a 64% decrease in hot flashes from baseline. A larger placebo-controlled study is being developed.
Capsaicin for Chronic Pain
Chronic pain can be a problem after mastectomy or limb amputations, he said. Capsaicin cream, a substance made from hot chili peppers, was tested in a placebo-controlled, double-blind study of 99 patients. Patients using the cream had significantly more pain relief throughout the entire 8 weeks of the study. The mean pain reduction was 53% in the capsaicin group vs 17% in the placebo group. Capsaicin cream is known to deplete substance P, a peptide involved in transmitting pain along the nerves.
Extract from the root of the valerian plant is an herbal substance commonly available and used for insomnia, restlessness, and anxiety. Dr. Loprinzi said that researchers are actively recruiting up to 200 cancer patients with insomnia for a randomized placebo-controlled trial to test the effectiveness of valerian.
Several products touted in the lay press have been tested and found wanting, he said. Laetrile from apricot pits was promoted as a promising cancer therapy in the 1970s. A controlled clinical trial with 178 cancer patients not only found no benefit but also found that too much laetrile led to blood cyanide levels near a lethal range. Similarly, there was no significant difference in survival between advanced cancer patients taking 10 g/d of vitamin C vs placebo. Likewise, green tea was found ineffective in a phase II trial of men with metastatic prostate cancer.