The Monte Carlo codes PENH, TOPAS and FLUKA have been used in this work to simulate proton dose distributions in materials of medical interest such as water, bone or titanium. It has been possible to verify the almost total agreement on crucial magnitudes such as the depth dose.
However, discrepancies have appeared in the multiple Coulomb scattering (MCS), that comes from the large number of collisions that take place in the interaction of the beam through a slab of material, which is responsible for the differences in the deposited dose curves at the central beam axis. From this MCS angles study, for now, better results compared with experimental data are generated with codes based on theoretical models and with experimental adjustment (TOPAS and FLUKA), than more detailed ones, such as PENH.
Finally, the nuclear models used by each of these programs have been also compared with experimental data from the Massachusetts General Hospital via the dose deposited at different radii of the incident axis in concentric cylinders inside a water tank. It has not been possible to obtain the desired accuracy but it has been achieved the verification of the high quality models for nuclear reactions of the codes and their importance in explaining the available experimental results.