Presently, there are no conclusive treatments for many types of cancer, mainly due to the advanced phase of the disease at the time of diagnosis and to the side effects of existing therapies. Present diagnostic and therapeutic procedures need to be improved to supply early detection abilities and perform a more specific therapy with reduced systemic toxicity. In this review, improvements in nanotechnology allowing the design of multifunctional nanoparticles for cancer detection, therapy, and monitoring are reported. Nanoparticles, thanks to the nanomaterials they are made of, can be used as contrast agents for various diagnostic techniques such as MRI, optical imaging, and photoacoustic imaging. Furthermore, when used as drug carriers, they can accumulate in tumor tissues through the passive or/and active targeting, protect encapsulated drugs from degradation, raise tumor exposure to chemotherapeutic agents improving treatment effects. In addition, nanocarriers can simultaneously deliver more than one therapeutic agent enhancing the effectiveness of therapy and can co-deliver imaging and therapy agents to provide integration of diagnostics, therapy, and follow-up. Furthermore, the use of nanocarriers allows to use different therapeutic approaches, such as chemotherapy and hyperthermia to exploit synergistic effects. Theranostic approach to diagnose and treat cancer show a great potential to improve human health, however, despite technological advances in this field, the transfer into clinical practice is still a long way off.
Keywords: contrast agents’ delivery; diagnosis; drug delivery; nanoparticles; theranostics; therapy.