A Comparison of the Cog and McNp Codes in Computational Neutron Capture Therapy Modeling, Part Ii: Gadolinium Neutron Capture Therapy Models and Therapeutic Effects

Abstract

The goal of this study was to evaluate the COG Monte Carlo radiation transport code, developed and tested by Lawrence Livermore National Laboratory, for gadolinium neutron capture therapy (GdNCT) related modeling. The validity of COG NCT model has been established for this model, and here the calculation was extended to analyze the effect of various gadolinium concentrations on dose distribution and cell-kill effect of the GdNCT modality and to determine the optimum therapeutic conditions for treating brain cancers. The computational results were compared with the widely used MCNP code. The differences between the COG and MCNP predictions were generally small and suggest that the COG code can be applied to similar research problems in NCT. Results for this study also showed that a concentration of 100 ppm gadolinium in the tumor was most beneficial when using an epithermal neutron beam.

Nanoparticles Containing Rare Earth Ions: A Tunable Tool for MRI

“…Most therapeutic protocols are now based on molecular boron compounds [151]. However, different groups have reported the possibility to take advantage of ␥ -ray emission and Auger electrons of gadolinium isotopes ( 155 Gd and 157 Gd) upon interaction with a thermal neutron [136,[152][153][154][155]. In particular, the in vitro study of Bridot and colleagues showed the therapeutic potential of hybrid nanoparticles combining high contrast properties and long blood half-life [131] and a size (7 nm in diameter) compatible with partial extravasation from the vasculature and cell targeting.…”