In vivo imaging of the neutron capture therapy agent BSH in mice using 10B MRI

Boron neutron capture therapy (BNCT) is an experimental cancer treatment modality requiring the targeting of B-10-enriched compounds to the tumor, which is then irradiated by low-energy neutrons, One of the boron-containing compounds used for this purpose is the mercaptoborane Na2B12H11SH (BSH). The first in vivo MR images of B-10-enriched BSH are presented here, BSH, injected into the tail vein of mice with implanted M2R melanoma xenografts, was imaged using 3D gradient echo B-10 MRI. B-10 NMR spectroscopy, localized mainly to the tumor by virtue of the use of a small surface coil, was applied to measure the T-1 (2.9 +/- 0.3 ms) and T-2 (1.75 +/- 0.25 ms) values of the B-10 signal, The MRI experiments detected levels of about 20 ppm (mug boron / g tissue) at 6 x 6 x 6 mm spatial resolution in a total scan time of 16 min. (C) 2001 Wiley-Liss, Inc.