Computation of relative biological effectiveness of low-energy electrons release in gadolinium neutron capture therapy based on microdosimetry
10.3760/cma.j.112271-20220822-00338
- VernacularTitle:基于微剂量学的钆中子俘获治疗释放低能电子相对生物效应计算
- Author:
Weiyue YU
1
;
Bing HONG
;
Peng LU
;
Lizhen LIANG
;
Ni CHEN
Author Information
1. 安徽医科大学基础医学院核医学教研室，合肥 230032
- Keywords:
157GdNCT;
Geant4;
Microdosimetry;
Relative Biological Effectiveness
- From:
Chinese Journal of Radiological Medicine and Protection
2023;43(5):373-378
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To calculate the relative biological effectiveness (RBE) value of the released low-energy electrons in gadolinium neutron capture therapy ( 157GdNCT) based on microdosimetry. Methods:The Monte Carlo (MC) code Geant4-DNA package was used to simulate the energy deposition distribution and microdosimetry parameters of low-energy electrons released during gadolinium neutron capture treatment in different sensitive target volumes and physical models on track structures. On this basis, RBE value was obtained based on the microdosimetry kinetic model (MKM).Results:The low-energy electron RBE value was highly variable in different sensitive target volumes and decreases with increasing sensitive target volumes. With 6-nm-diameter sensitive target as reference, RBE value was 1.77 for 6-nm diameter, 1.53 for 10 nm diameter with percentage difference 13%, and 1.40 for 15-nm diameter with percentage difference of 21%, respectively. The effect of different Geant4-DNA physical models on the RBE of low-energy electrons was small. Using the RBE value of 1.53 for physical model option2 as reference, the RBE values of option6 and option7 were 1.49 and 1.52, respectively, with the percentage differences of 2.6% and 0.6%, respectively.Conclusions:The RBE values of low energy electrons released by 157GdNCT in different sensitive target volumes and physical models were calculated by MKM to be 1.40-1.77.
