Radiation Dose Enhancement in Megavoltage Radiation Therapy using Au, Gd, Pt, Ag, and Bi Nanoparticles of Various Concentration Level

A digital phantom as created from a CT scan of a patient's head and employed together with GATE 8.2 Monte Carlo modeling of a linear accelerator of nominal 6 MV energy to simulate an irradiation geometry for a typical tumor volume centrally within the brain region. Although simplistic in arrangement this setup as considered appropriate to demonstrate the dose enhancements that may be expected for megavoltage external beam radiation therapy for nanoparticles (NP) of different elemental composition and concentration. Ag, Gd, Pt, Au and Bi ere modeled in concentrations varying from 15 mg NP / gram tissue to 70 mg NP / gram tissue. The maximum Average Dose Enhancement Factor (ADEF) to the Gross Tumour Volume (GTV) observed as 3 % for 70 mg NP / gram tissue of Bi.