Dosimetry Impact of Boron and Its Carriers Structure at Boron Neutron Capture Therapy of a Brain Tumor; A Sim- ulation Study

Introduction: Boron neutron capture therapy (BNCT) is a method of cancer treatment and potentially, two borono-L-phenylalanine (BPA) and sodium borocaptate (BSH) are used in BNCT as common boron carriers. Some previous studies have shown that the dose rate is directly related to boron concentration in the tissue. This study aimed to simulate the structure of boron carriers and brain tumor compounds according to the real clinical condition. Moreover, the effect of carrier concentration in tumor volume and boron concentration in carrierschr('39') structure would be numerically assessed. Methods: First, a phantom is developed by FLUKAsimulation code to perform dosimetry aspects of Boron and carriers on a typical brain tumor. Moreover, the components of carriers were then simulated separately and the dosimetry parameters were assessed by changing the amount of boron in the carriers’ structure and by the carrierschr('39') concentration variations inside and around the tumor to mimic the real condition. Results: The results showed that by increasing boron inside the BPA structure from 5.17% to 50%, the dose will be increased up to 78.46%. In the BSH, tumor dose is raised to 9.06% by increasing the amount of boron concentration at carrier structure from 59% to 80%. Moreover, by enhancing the two carrierschr('39') concentration inside the tumor volume up to 30%, the dose value is increased up to 9.59% and 3.20% for BPA and BSH carriers, respectively. Conclusions: The level of boron in the carrierchr('39')s structure and also carrierschr('39') concentration is highly remarkable on dose delivery inside tumor volume and surrounding tissues.