Jin Will H, Seldon Crystal, Butkus Michael, Sauerwein Wolfgang, Giap Huan B
Department of Radiation Oncology, Jackson Memorial Hospital/Sylvester Comprehensive Cancer Center, University of Miami Health Systems, Miami, FL, USA.
Deutsche Gesellschaft für Bor-Neutroneneinfangtherapie (DGBNCT), Universitätsklinikum Essen, Essen, Germany.
Int J Part Ther. 2022 Jun 9;9(1):71-82. doi: 10.14338/IJPT-22-00002.1. eCollection 2022 Summer.
External beam, whether with photons or particles, remains as the most common type of radiation therapy. The main drawback is that radiation deposits dose in healthy tissue before reaching its target. Boron neutron capture therapy (BNCT) is based on the nuclear capture and fission reactions that occur when B is irradiated with low-energy (0.0025 eV) thermal neutrons. The resulting B(n,α)Li capture reaction produces high linear energy transfer (LET) α particles, helium nuclei (He), and recoiling lithium-7 (Li) atoms. The short range (5-9 μm) of the α particles limits the destructive effects within the boron-containing cells. In theory, BNCT can selectively destroy malignant cells while sparing adjacent normal tissue at the cellular levels by delivering a single fraction of radiation with high LET particles.
BNCT has been around for many decades. Early studies were promising for patients with malignant brain tumors, recurrent tumors of the head and neck, and cutaneous melanomas; however, there were certain limitations to its widespread adoption and use.
Recently, BNCT re-emerged owing to several developments: (1) small footprint accelerator-based neutron sources; (2) high specificity third-generation boron carriers based on monoclonal antibodies, nanoparticles, among others; and (3) treatment planning software and patient positioning devices that optimize treatment delivery and consistency.
外照射，无论是光子还是粒子，仍然是最常见的放射治疗类型。主要缺点是辐射在到达靶标之前会在健康组织中沉积剂量。硼中子俘获疗法（BNCT）基于用低能（0.0025电子伏特）热中子照射硼时发生的核俘获和裂变反应。由此产生的B（n，α）Li俘获反应产生高线性能量转移（LET）α粒子、氦核（He）和反冲锂-7（Li）原子。α粒子的短射程（5-9微米）限制了含硼细胞内的破坏作用。理论上，BNCT可以通过单次给予高LET粒子辐射，在细胞水平上选择性地破坏恶性细胞，同时保留相邻的正常组织。
BNCT已经存在了几十年。早期研究对恶性脑肿瘤、头颈部复发性肿瘤和皮肤黑色素瘤患者很有前景；然而，其广泛采用和使用存在一定局限性。
最近，由于以下几个方面的发展，BNCT重新兴起：（1）基于小型加速器的中子源；（2）基于单克隆抗体、纳米颗粒等的高特异性第三代硼载体；（3）优化治疗输送和一致性的治疗计划软件和患者定位设备。
