Nearly four out of every 10 Americans use some form of complementary and alternative medicine -- CAM -- to address a concern with their health. When megadose vitamins and healing prayer are included, the number jumps to more than six out of every 10. Is it possible that some form of CAM can be beneficial in the treatment of breast cancer? For example, what about acupuncture or tai chi? Can they add anything as a supplement to standard medical care?