Atherosclerosis is the accumulation of fatty plaque in arteries, a major cause of heart attack and stroke. A group of researchers at Stanford University has discovered that a drug commonly used in cancer therapy may be effective in partially dissolving blockages. Only a few types of cells absorb the drug lutetium texaphyrin. These include cancer cells and a cell that plays a role in the formation of plaque. The cells die only after exposure to high-intensity red light. The researchers injected lutetium texaphyrin in 16 patients who had blocked leg arteries. A day later they delivered red light through a fiber optic probe, inserted into a small slit in the artery. After four weeks, 12 of the 16 patients experienced a noticeable reduction in plaque deposits.