According to research, cancer is the second leading cause of death globally. Around 18.1 million new cases and 9.5 million cancer-related deaths were seen worldwide in 2018 alone, and this number is expected to rise in the upcoming years. Radiotherapy, also called radiation therapy, proves out to be one of the most effective ways for the treatment of cancer. Around 50% of all cancer patients could benefit from radiotherapy in the management of their disease. If diagnosed early enough, about half of those patient’s cancer might be curable.
The limiting factor of radiation therapy is that the doses high enough to treat high-risk (locally advanced) non-metastatic tumors also damage the surrounding healthy tissues. Currently, there is a limit on the radiation therapy dose that can be prescribed for patients. Therefore, new methods are needed that increase the radiation effectiveness and reduce its side effects.
One possibility is to make tumor cells more sensitive to radiation so that these cells become more susceptible to damage from radiation therapy. The use of gold nanoparticles as a radiosensitizer has shown some promising results. These gold nanoparticles can be injected intravenously to accumulate in the tumor by exploiting the defective tumor blood vessel wall. Due to their rapid growth, these blood vessel walls tend to leak out. Gold nanoparticles interact with the photons of X-rays, which produces the electrons which then interact with water molecules to produce free radicals. These free radicals lower the survival of tumor cells by damaging them.