Abstract :
Malignant diseases are among prevalent health problems in developing and developed countries.
Cancer is the second cause of death in developed countries and the third or fourth in developing
countries depending on the age pattern of communities and fronting them with risk factors. Therefore,
cancer management is of prime importance and deserves more attention from health policy makers
and managers worldwide. Health policy makers should keep an eye on the changes in incidence,
prevalence, and burden of malignant diseases, and should also monitor changes in cancer diagnosis
and treatment. With a history of more than 50 years, radiation therapy has become one the most
efficient and popular procedures in cancer management in recent decades. More than 60% of cancer
cases need radiation therapy. Different rays such as: X-Ray, Gamma Ray, Electron, and so on are used
treat different types of cancer. Linear accelerator machines are more popular in radiation
departments as they have provided great opportunity for cancer management, and improved the use
of new X-Ray machines for treating special cases. The main goal of radiation therapy is as follows:
1) Dose distribution between tumors
2) Dose limiting normal tissue
3) Respect normal tissue tolerance
