Since the advent of cancer nanotechnology, researchers have sought to use magnetic fields to increase the concentration of drug-loaded iron oxide nanoparticles that reach a tumor. However, magnetic fields drop off quickly with distance, making it almost impossible to consider such an approach for tumors located more than a few centimeters from the skin. To solve what appears to be a fundamentally unsolvable problem, researchers at the Stanford University Center of Cancer Nanotechnology Excellence (Stanford CCNE) have taken a two-pronged approach, one that uses an external magnetic field and an implantable magnetizable mesh to create local magnetic fields strong enough to trap nanoparticles at a specific location.