Lithium neutron capture therapy opens new possibilities in cancer treatment
Lithium neutron capture therapy opens new possibilities in cancer treatment lead image
Activation therapy targets non-resectable tumors, which cannot be surgically removed, by selectively concentrating stable isotopes in tumor cells, applying an external beam, and activating the deposited atoms. One such technique is boron neutron capture therapy (BNCT).
Several challenges persist in the clinical implementation of BNCT, however. Precise delivery of boronated compounds to a tumor mass is difficult and the BNCT reaction range is small, less than the radius of an average cell. Furthermore, 94% of its reactions emit gamma rays, ionizing healthy tissues as they exit the body. To solve these problems, Morris et al. proposed lithium neutron capture therapy (LiNCT) as a potential alternative treatment modality.
“LiNCT is the only therapy for which such a high dose concentrated upon a small area is feasible,” said author Austin Morris. “Because 6Li is a stable ion, whose neutron capture products are instantaneous and self-limiting, the process is completely controlled by the neutron beam, which provides an ‘on’ and ‘off’ switch.”
In addition to reactions spanning as large as the diameter of some astrocytes, LiNCT generates significantly fewer gamma rays, which could enable safely applying higher radiation doses. For rapid treatment options, the authors highlighted an irradiation scheme utilizing a laser-driven neutron source — the first proposal of a FLASH neutron capture therapy.
The authors expect cancer radiation therapy to become more targeted, starting from the development of a 6Li tumor delivery compound.
“Greater impact will hopefully arise from using lithium nanoparticles, limiting direct cell exposure to lithium cations, which are toxic,” said Morris. “This would allow us to increase the drug concentration and better evaluate the possibility of ultra-high doses.”
Source: “Advancing lithium neutron capture therapy: 6Li-loaded nanoparticles and laser-driven neutron sources,” by Austin A. Morris, Jianfeng Lv, and Yuanrong Lu, Applied Physics Letters (2024). The article can be accessed at https://doi.org/10.1063/5.0185189 .
