A great deal of clever engineering is taking place in the development of new methods of targeting, delivering and activating pinpoint anti-cancer therapies. This technology will have utility in the future - the ability to target very small areas or very specific types of cell in the body opens up all sorts of possibilities throughout medicine. Here is an example via Israel21c: "The two big problems with photodynamic therapy are getting the light-sensitive drug to only target cancer cells, and delivering light to the drug to activate it once it is in the right place. We've uniquely combined two cutting-edge technologies to direct a drug to cancer cells and to generate a light source inside the cells. This stops the drug killing healthy cells ... we've shown in the research that if you take a cell culture and treat it with the light sensitive compound called luminol - it produces chemiluminescence in the cell which activates the light sensitive molecules and kills the cells. ... We're now in the pre-clinical stage using models of leukemia, but we're not limited to that cancer."