Monitoring Of Blood-B-10 Concentration For Boron Neutron-Capture Therapy Using Prompt Gamma-Ray Analysis

The aim of the present study was to monitor the blood-B-10 concentration of laboratory dogs receiving boron neutron capture therapy, in order to obtain optimal agreement between prescribed and actual dose, A prompt gamma-ray analysis system was developed for this purpose at the High Flux Reactor in Petten, The technique was compared with inductively coupled plasma-atomic emission spectrometry and showed good agreement, A substantial variation in B-10 clearance pattern after administration of borocaptate sodium was found between the different dogs, Consequently, the irradiation commencement was adjusted to the individually determined boron elimination curve, Mean blood-B-10 concentrations during irradiation of 25.8 +/- 2.2 mu g/g (1 SD, n = 18) and 49.3 +/- 5.3 mu g/g (1 SD, n = 17) were obtained for intended concentrations of 25 mu g/g and 50 mu g/g, respectively, These variations are a factor of two smaller than irradiations performed at a uniform post-infusion irradiation starting time, Such a careful blood-B-10 monitoring procedure is a prerequisite for accurately obtaining such steep dose-response curves as observed during the dog study.