BNCT Microdosimetry of a Rat Glioma Model with BPA-F or BSH
The BNCT microdosimetry technique developed in the Harvard-MIT BNCT Program involves both experimental and computational components. First, a neutron-induced alpha particle track etch technique developed in our laboratory termed High Resolution Quantitative Autoradiography (HRQAR) is used to measure the microscopic distribution of 10B in a thin tissue section.1 HRQAR allows simultaneous visualization of tissue histology and track etch pits, which sample the 10B microdistribution. The polycarbonate track detector used in the technique is sensitive only to high LET particles (not protons) and has a linear response and sensitivity down to ~1 μg/g10B. By employing the actual boron microdistribution and tissue morphology obtained with the HRQAR technique in a 2D Monte Carlo simulation of charged particle transport and energy deposition in tissue, our approach to BNCT microdosimetry circumvents the simplifying assumptions usually required in microdosimetry, i.e., using elementary mathematical shapes and functions to represent the tissue architecture and boron distribution. This paper will discuss microdosimetric results obtained for 9L gliosarcoma in rats injected with boronophenylalanine-fructose (BPA-F) or Na2B12H11SH (BSH) using the HRQAR-based microdosimetry technique.
KeywordsNeutron Capture Boron Neutron Capture Therapy Heavy Charged Particle Track Etch ICRU Report
Unable to display preview. Download preview PDF.
- 2.International Commission on Radiation Units and Measurements, “Photon, electron, proton, and neutron interaction data for body tissues,” ICRU Report 46, Bethesda, Md., U.S.A, 1992.Google Scholar
- 3.J.F. Ziegler, SRIM98, “The Stopping and Range of Ions In Matter,” IBM Research, Yorktown, NY (1998). http://www.research.ibm.com/ionbeams/SRIM/SRIMINTR.HTMGoogle Scholar
- 4.International Commission on Radiation Units and Measurements, “Microdosimetry,” ICRU Report 36, Bethesda, Md., U.S.A, 1983.Google Scholar
- 6.G. Solares, W.S. Kiger III, and R. Zamenhof, “Microdosimetry Studies at the Harvard/MIT Phase-I Clinical Trial of Boron Neutron Capture Therapy,” in Advances in Neutron Capture Therapy, edited by B. Larsson, J. Crawford, and R. Weinreich, Elsevier, Amsterdam (1997).Google Scholar
- 7.C.S. Yam, “Microdosimetric Studies for Neutron Capture Therapy and Techniques for Capture Element Selection,” Ph.D. Thesis, Massachusetts Institute of Technology, 1995.Google Scholar
- 8.C.S. Yam, G.R. Solares, and R.G. Zamenhof, Verification of the Two-Dimensional Approach for NCT Microdosimetry, Trans. Am. Nucl. Soc., 71:142, 1994.Google Scholar
- 9.T. Kageji, S. Nagahiro, K. Matsumoto, B. Otersen, D. Gabel, M. Nakaichi, and Y. Nakagawa, Subcellular biodistribution of Na2B12H11SH (BSH) in a rat glioma model, in “Frontiers in Neutron Capture Therapy,” M.F. Hawthorne, K. Shelly, R.W. Wiersema, eds., Kluwer Academic/Plenum Publishers, New York, 2001, pp. 927–931.CrossRefGoogle Scholar
- 10.S. Chandra, D.R. Lorey, D.R. Smith, and G.H. Morrison, In Vitro exposure of human T98G glioblas- toma cells to mixed BNCT drugs: acquiring independent quantitative images of boron atoms delivered by 10BPA-F and 11BSH in the same cell by SIMS ion microscopy, in “Frontiers in Neutron Capture Therapy,” M.F. Hawthorne, K. Shelly, R.W. Wiersema, eds., Kluwer Academic/Plenum Publishers, New York, 2001, pp. 905–909.CrossRefGoogle Scholar