Recently, research in the field of cancer nanotechnology has made notable progress, and, with the fast development of nanomaterials, new treatment strategies using nanoparticles are being explored that have the potential to overcome existing problems. The present review focuses on patenting as a key indicator of trends in nanoparticles with applications in the treatment of cancer. The impact of cancer on health and the use of nanoparticles are briefly described. Next, a survey of patents filed in the last 14 years is presented, the patents granted in the last four years are identified, and the focus areas of the main applicants are analyzed. The mix of targets identified for patented nanoparticles systems suggests that polymers and proteins are the main focus of the innovative efforts in this field.