Radiation Sensitivity of in Vitro Evaluation System of Pharmacokinetics in Boron Neutron Capture Therapy (BNCT) Using Three-Dimensional Artificial Human Tumor Tissue Model

One of the important matters that must be determined in advance when performing BNCT treatment is the optimization of neutron irradiation time and dose. In this article, following the previous article (2.52 × 1012 n/cm2) (Case 1), double irradiation (5.04 × 1012 n/cm2) was further performed (Case 2) by verifying the radiation sensitivity performance of the artificial tumor tissue NHDF3D/BxPC3 and the possibility of evaluating the optimum neutron dose required for treatment was examined. As a result, although the radiation damage rate in the normal tissue NHDF3D and the tumor tissue BxPC3 increased in proportion to the irradiation dose due to heavy irradiation in Case 1 or more, the increase in the damage rate in the normal tissue exceeded the tumor tissue. Furthermore, the tumor/normal tissue damage ratio T/N ratio showed the maximum value in Case 1, and the dose ratio in Case 2 with a higher dose showed a tendency to decrease. From the above experimental facts, it was shown that irradiation dose optimization is possible to some extent by an evaluation method using an artificial tumor tissue.