About Boron Neutron Capture Therapy

Boron Neutron Capture Therapy (BNCT) is a multi-step combination therapy. A cancer patient is first administered a boron target drug that preferentially binds to and carries non-toxic boron-10 to malignant cells. The tumor tissue is then showered with a beam of low energy neutrons at a level and spectrum optimal for reaction with the boron-10. This reaction, inside the cells, emits charged particles that destroy the cell while limiting damage to surrounding healthy tissue without boron-10. Once the beam reacts with the boron in the cancer cells, the relative biological effectiveness (RBE) is significantly higher than in most other forms of radiation therapy.² This secondary radiation reaction, with cellular-level precision, spares more healthy tissue and can potentially treat cancers that otherwise have few treatment options due to their proximity to critical tissue.¹

In addition, delivering radiation treatment that is more selectively focused on tumor cells while limiting damage to healthy tissue results in improved patient quality of life. BNCT has been shown to be convenient and comfortable; it is typically delivered in only one or two sessions, providing an improved experience compared to traditional radiation therapies, which are administered over many weeks.¹

With such potential, why hasn't BNCT been more readily available? Investigation of the treatment first began decades ago, but has historically been limited by the need for a nuclear reactor source for neutrons. Despite this challenge, a small number of clinical sites throughout the world have seen encouraging preliminary results with BNCT in limited patient studies. While these dedicated oncologists and researchers have worked to investigate BNCT for head and neck, GBM and other challenging cancers, the ability to broadly offer this treatment has been waiting for development of an affordable, conveniently available neutron source that can be practically installed and operated in a hospital setting.

1. Moss, R. L. Critical review, with an optimistic outlook, on Boron Neutron Capture Therapy (BNCT). Applied Radiation and Isotopes 88 (2014), 2–11.Sauvolainen, S., et al. Boron neutron capture therapy (BNCT) in Finland: Technological and physical prospects after 20 years of experiences. Physica Medica (2013) 29, 233-248.

2. Wang, Ling-Wei, et al. Fractionated BNCT for locally recurrent head and neck cancer: Experience from a phase I/II clinical trial at Tsing Hua Open-Pool Reactor. Applied Radiation and Isotopes 88(2014), 23–27.