ABSTRACT
Cancer is the leading cause of death in economically developed countries and the second leading cause of death in developing countries. Millions of people worldwide are diagnosed with cancer in each year, and approximately half of the people who develop cancer each year receive radiation therapy as a component of their treatment. Cancer is also the second leading cause of death in the United States and accounts for approximately one in every four deaths. Many researchers around the world are investigating ways to improve the outcome of current radiation-based therapeutics techniques. As a step forward in this direction, radiation enhancers are being explored for enhancing the therapeutic eects of radiation. Radiation enhancers could cause more tissue damage by increasing the absorption or scattering of the radiation, and cause more local energy deposition. High atomic number (Z) materials are being used as radiation enhancers. ese can be introduced into the target material, such as tumor, to increase the probability of ionization events leading to enhanced deposition of energy to destroy tumor tissues. However, delivering a curative dose of radiation to tumor tissues while sparing normal tissues is still a great challenge in radiation therapy. Major milestones achieved toward improved cancer care through enhancing radiation dose will be discussed in the next section (see Figure 9.1).
