The conditions for the possible initiation of clinical trials with neutron capture therapy at a number of locations in the U.S. is reviewed. There are several new technical developments or plans at the Brookhaven Medical Research Reactor (BMRR), the Power Burst Facility (PBF) at INEL, the Massachusetts Institute of Technology Reactor (MITR) and the Georgia Institute of Technology Research Reactor (GTRR). Emphasis is on the development of epithermal beams for the treatment of deepseated tumors with neutron fluxes in between 109 to 1010 n/cm2 s. Therapeutic dose gains, defined as the ratio of tumour dose to maximum normal tissue dose in the treatment volume are expected to be between 2 and 4, depending on the degree of suppression of fast neutron dose. Boron concentrations considered in this case in the tumour are around 35 μg 10B/g and tumour/normal tissue concentrations are around 10. The compound development throughout three generations is discussed. The compound proposed nowadays, Na2B12H11SH (or BSH), employed in the treatments in Japan, will likely be replaced in the future by analogues of biomolecules being enriched in the tumour by physiological pathways. Examples are p-boronophenylalanine or boronated porphyrins. The most promising solution envisaged would be the employment of tumour cell specific boronated monoclonal antibodies. Finally the mode of therapy is discussed which will likely be based on a fractionated scheme, to achieve optimized results.
|Number of pages||5|
|Journal||Strahlentherapie und Onkologie|
|State||Published - 1 Jan 1989|