Cancer is not a tumor so nanoparticles are just a stop-gap measure. When you kill one tumor then another one appears. why? Because you didn't kill the cancer. Let me define cancer correctly. It is the biochemical imbalance in the body that allow tumors to grow. We all produce cancer cells but most peoples immune system kill them before they develop into tumors. read more at http://www.dragonfly75.com/eng/cancer.html