A study of 750 patients around the country found that most use prayer, relaxation techniques, exercise and sometimes herbs or megavitamins on top of their medical therapies. "We were a bit surprised by how many people were using these techniques," said Jennifer Yates, an information analyst at the University of Rochester in New York who led the study. "And we don't really know why they're using them -- to beat the cancer or to ease the side effects of treatment. Those are questions we still have to ask."