He taught them to practice special relaxation techniques and found that the strategy reduced problems with nausea and vomiting. More surprising was the finding that patients who used relaxation techniques survived longer. Thinking that the results may have been a fluke, Walker set up a new trial. His research team sought to determine whether relaxation and imagery techniques could control the spread of breast cancer cells after tumors had been removed by conventional treatment. A total of 96 women participated in the new study. All underwent conventional treatment for removal of their tumors. However, half of them also spent time each day imagining that their tumor was being attacked. Christine describes how, in seeking to control the spread of her cancer, she imagined a monster imprisoned in a cage. Over a period of three years, the researchers assessed the natural killer cells in the participants' blood, which are thought to inhibit the spread of cancer. They found that relaxation and imagery techniques enhanced the white cells that are important in targeting and fighting cancer cells. The study is not complete, but preliminary results suggest that the women who practiced relaxation and imagery techniques also had more active natural killer cells. Although the strategy does not provide a cure, it may help prevent the spread of cancer throughout the body.