Abstract:
Radiation therapy is a form of high energy gamma rays which can destroy or prevent the spread of cancer. It has been long known that patients treated with ionizing radiation carry a risk of developing a second cancer in their lifetimes. Factors that contribute to the restate of cancer (or may be called second cancer) includes improved cancer survival rate by using high radiations as well as emerging treatment modalities. These modalities such as intensity-modulated radiation treatment (IMRT). They can potentially elevate secondary exposures to healthy tissues distant from the target volume.
In this study, cancer is treated with high-energy radiations. To provide radiation to the organ, external beam radiotherapy is performed. The target volume has been selected is the pelvic organ. The surrounding tissues and OARs of the pelvic organs include the bladder, rectum, small bowl, and LT and RT femoral heads. As a result, the goal of this work is to evaluate and compute the impact of high energy photons on these pelvic surrounding tissues. By using radiation beams for constant half value layer (HVL) and field size we determine the PDD and observe the path of radiation. Also we have check the variation in different parameters for closed applicators and diaphragm limited. For this we calculated values for different depths and field size and observe the PDD. A high energy through linear accelerator is used to strike the target in cancer treatment. Thus Mathematical & biological model (LQM) is used as a tool to calculate the Biological Effective Dose (BED) and Biological Equivalent Dose (EQD2) with dose per fraction for different Organs at Risk (OAR’s) nearer to the pelvic. The LQ model is further examined in the context of tumor control probability (TCP) models. Then we use the Radiobiological considerations can be utilized in a variety of therapeutic settings, and all physicians should be aware of the potential advantages of incorporating a quantitative radiobiological approach into their practice. Moreover, the aim of this study is to provide an understanding of the principles and methods related to scattered doses in surrounding organs to check and optimize the dose plan in radiation therapy by summarizing a large collection of dosimetry and clinical studies.
