Monte Carlo modeling of electron beams from a NEPTUN 10PC medical linear accelerator

Electron beam radiation therapy is used extensively for treating head and neck cancers to avoid the irradiation of the spinal cord. It is also used for treating chest wall malignancies to limit the irradiated volume of lungs. Calculating the dose distribution from an electron field is quite complicated because of the multiple scattering, especially in the presence of internal heterogeneities [18]. The Monte Carlo method can precisely model the physical processes involved in radiation therapy and is powerful in dealing with any complex geometry [15]. Ever since the first appearance of Monte Carlo techniques in radiotherapy physics, physicists have been making steady progress towards full-scale treatment planning using a Monte Carlo dose engine [21]. The currently available commercial systems for electron treatment planning are associated with large uncertainties, especially in irradiated volumes containing inhomogeneities such as air cavities and bones. The Monte Carlo method is generally considered to be the most accurate approach for electron dose calculation under all circumstances [13, 16]. A Monte Carlo treatment planning system needs detailed information about the beams incident on the Monte Carlo modeling of electron beams from a NEPTUN 10PC medical linear accelerator Nasrollah Jabbari, Bijan Hashemi-Malayeri