Nanoengineered delivery systems for cancer imaging and therapy: recent advances, future directions and patent evaluation.

Cancer is the second-highest cause of death worldwide. Several therapeutic approaches, such as conventional chemotherapy, antibodies and small-molecule inhibitors and nanotherapeutics, have been employed in battling cancer. Among them, nanotheranostics is an example of successful personalized medicine bearing the dual role of early diagnosis and therapy to cancer patients. In this review, we focus on various types of theranostic polymer and metal nanoparticles for their roles in cancer therapy and imaging concerning their limitations and future applications, such as dendritic cell cancer vaccination, gene delivery, T cell activation and immune modulation. Some of the recorded patent applications and clinical trials are illustrated and the impact of the biological microenvironment on the biodistribution and accumulation of nanoparticles is also discussed.