Neutron Therapy

Japan and Italy are leading in BNCT (Boron Neutron Capture Therapy), which conceptually promises low entrance and exit doses. BNCT is not yet widely available, not that it is exclusive for the wealthy, but that the concept has yet to be fully translated into practice. Lots of radiopharmacy research still needs to be done. It works a bit like 18F-FDG PET (Positron Emission Tomography), in that a tumour seeker is bound chemically to a radioisotope (10Boron instead of 18Fluorine). The tumour seeker leads the way in the blood stream, and brings the radioisotope to the site of action (the tumour). Before reaching the site of action, the radioisotope does nothing, ensuring no entrance dose. Only after reaching the site of action, the radioisotope delivers a dose with a range short enough to ensure no exit dose. This action is triggered by an external neutron beam. Note that BNCT is particle therapy, not neutron therapy. It is lithium and alpha particles which deliver the dose. Neutrons act only as a trigger. Neutron therapy is a bit of a taboo and is better not mentioned, following some horrific clinical trials decades ago.