Chiniforoush Tayebeh A, Hadadi Asghar, Kasesaz Yaser, Sardjono Yohannes
Department of Medical Radiation Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran.
Appl Radiat Isot. 2021 Apr;170:109596. doi: 10.1016/j.apradiso.2021.109596. Epub 2021 Jan 22.
Recently it has been suggested that the presence of boron-11 during proton therapy leads to a significant dose increasement in the BUR. Three high-LET alpha particles with an average energy of 4 MeV are generated at the point of interaction between proton and boron-11. Nevertheless, the cross-section of p+B11→3α interaction is negligible and dose increasement is unlikely. The purpose of this study is dose evaluation of the proton therapy with and without the boron-11. All simulations were performed using MCNPX 2.6.0 code at the Snyder head phantom. At the elderly stage, the range of Bragg-peaks was adapted to the tumor volume, with and without boron-11. Then, the different concentrations of boron-11 were assumed including 65,500,10,10,2.5×10 and 5×10ppm in the tumor region. To investigate the maximum effectiveness of PBFT (proton boron fusion therapy), the entire tumor was assumed full of boron-11, and the dose components were calculated. Consequently, In the best case, the maximum dose amplification was less than 5%, in which the entire tumor was assumed full boron-11. The total number of alpha particles generated from p+B11→3α interaction is negligible. As well as the presence of boron-11 during the proton therapy makes that the Bragg-peaks happen in greater depth. Hence, from the Monte Carlo standpoint, the effectiveness of the proton boron fusion therapy is not related to the alpha particles because the dose component of alpha particles is negligible.
最近有人提出，质子治疗期间硼 - 11的存在会导致布拉格峰区（BUR）剂量显著增加。在质子与硼 - 11的相互作用点会产生三个平均能量为4 MeV的高传能线密度（LET）α粒子。然而，p + B11→3α相互作用的截面可忽略不计，剂量增加不太可能。本研究的目的是评估有硼 - 11和无硼 - 11时质子治疗的剂量。所有模拟均使用MCNPX 2.6.0代码在斯奈德头部模型上进行。在老年阶段，有硼 - 11和无硼 - 11时，布拉格峰的范围都与肿瘤体积相适应。然后，假设肿瘤区域中硼 - 11的浓度不同，包括65500、10、10、2.5×10和5×10 ppm。为了研究质子硼融合治疗（PBFT）的最大有效性，假设整个肿瘤充满硼 - 11，并计算剂量成分。因此，在最佳情况下，最大剂量放大率小于5%，即假设整个肿瘤充满硼 - 11。由p + B11→3α相互作用产生的α粒子总数可忽略不计。而且质子治疗期间硼 - 11的存在会使布拉格峰出现在更深的位置。因此，从蒙特卡罗的角度来看，质子硼融合治疗的有效性与α粒子无关，因为α粒子的剂量成分可忽略不计。
