Monte Carlo Based Dosimetry and Treatment Planning for Neutron Capture Therapy of Brain Tumors

  • R. G. Zamenhof
  • S. D. Clement
  • O. K. Harling
  • J. F. Brenner
  • D. E. Wazer
  • H. Madoc-Jones
  • J. C. Yanch
Part of the Basic Life Sciences book series (BLSC, volume 54)


Monte Carlo based dosimetry and computer-aided treatment planning for neutron capture therapy have been developed to provide the necessary link between physical dosimetric measurements performed on the MITR-II epithermal-neutron beams and the need of the radiation oncologist to synthesize large amounts of dosimetric data into a clinically meaningful treatment plan for each individual patient. Monte Carlo simulation has been employed to characterize the spatial dose distributions within a skull/brain model irradiated by an epithermal-neutron beam designed for neutron capture therapy applications. The geometry and elemental composition employed for the mathematical skull/brain model and the neutron and photon fluence-to-dose conversion formalism are presented. A treatment planning program, NCTPLAN, developed specifically for neutron capture therapy, is described. Examples are presented illustrating both one and two-dimensional dose distributions obtainable within the brain with an experimental epithermal-neutron beam, together with beam quality and treatment plan efficacy criteria which have been formulated for neutron capture therapy. The incorporation of three-dimensional computed tomographic image data into the treatment planning procedure is illustrated. The experimental epithermal-neutron beam has a maximum usable circular diameter of 20 cm, and with 30 ppm of B-10 in tumor and 3 ppm of B-10 in blood, it produces (with RBE weighting) a beam-axis advantage depth of 7.4 cm, a beam-axis advantage ratio of 1.83, a global advantage ratio of 1.70, and an advantage depth RBE-dose rate to tumor of 20.6 RBE-cGy/min (cJ/kg-min). These characteristics make this beam well suited for clinical applications, enabling an RBE-dose of 2,000 RBE-cGy/min (cJ/kg-min) to be delivered to tumor at brain midline in six fractions with a treatment time of approximately 16 minutes per fraction. With parallel-opposed lateral irradiation, the planar advantage depth contour for this beam (with the B-10 distribution defined above) encompasses nearly the whole brain. Experimental calibration techniques for the conversion of normalized to absolute treatment plans are described.


Neutron Beam Boron Neutron Capture Therapy Experimental Beam Integral Dose Dose Component 


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  1. 1.
    G. L. Brownell, R. G. Zamenhof, B. W. Murray, and G. R. Wellum, “Boron Neutron Capture Therapy,” in Therapy in Nuclear Medicine, R. P. Spencer, ed., Grime and Stratton, Inc., New York (1978).Google Scholar
  2. 2.
    Proc. Third Int. Symp. on Neutron Capture Therapy, Strahlenther. Onkol., D. Gabel, ed., 165(2/3):5–257 (1989).Google Scholar
  3. 3.
    G. L. Locher, “Biologic Effects and Therapeutic Possibilities of Neutrons,” Am. J. Roentgenol., 36:1 (1936).Google Scholar
  4. 4.
    H. Hatanaka, “Clinical Experience of Boron-Neutron Capture Therapy for Gliomas — A Comparison with Conventional Chemo-Immuno-Radiotherapy,” in Boron-Neutron Capture Therapy for Tumors, H. Hatanaka, ed., Nishimura Co., Ltd., Niigata, Japan, p. 349 (1986).Google Scholar
  5. 5.
    A. H. Soloway, “Chemical Aspects of Neutron Capture Therapy,” in Radionuclide Applications in Neurology and Neurosurgery, Y. Wang and P. Paoletti, eds., Charles Thomas, Springfield, IL (1970).Google Scholar
  6. 6.
    R. G. Fairchild, “Development and Dosimetry of an ‘Epithermal’ Neutron Beam for Possible Use in Neutron Capture Therapy, ” Phys. Med. Biol., 10 (4): 491 (1965).CrossRefGoogle Scholar
  7. 7.
    R. G. Zamenhof, B. W. Murray, G. L. Brownell, G. R. Wellum, and E. I. Tolpin, “Boron Neutron Capture Therapy for the Treatment of Cerebral Gliomas: I. Theoretical Evaluation of the Efficacy of Various Neutron Beams,” Med. Phys., 2(2):47 (1975).PubMedCrossRefGoogle Scholar
  8. 8.
    R. G. Fairchild and V. P. Bond, “Current Status of B-10 Neutron Capture Therapy: Enhancement of Tumor Dose via Beam Filtration and Dose Rate, and the Effects of these Parameters on Minimum Boron Content: A Theoretical Evaluation,” Int. J. Radiat. Oncol. Biol. Phys., 11(4):831 (1985).PubMedGoogle Scholar
  9. 9.
    O. K. Harling, S. D. Clement, J. R. Choi, J. A. Bernard, and R. G. Zamenhof, “Neutron Beams for Neutron Capture Therapy at the MIT Research Reactor,” Strahlenther. Onkol., 165(2/3):90 (1989).PubMedGoogle Scholar
  10. 10.
    R. G. Zamenhof, S. D. Clement, K. Lin, C. Lui, D. Ziegelmiller, and O. K. Harling, “Monte Carlo Treatment Planning and High-Resolution Alpha-Track Autoradiography for Neutron Capture Therapy,” Strahlenther. Onkol., 165(2/3): 188 (1989).PubMedGoogle Scholar
  11. 11.
    R. G. A. Zamenhof, H. Madoc-Jones, O. K. Harling, and J. A. Bernard, Jr., “Clinical Considerations in the Use of Thermal and Epithermal Neutron Beams for Neutron Capture Therapy,” in Proc. 1988 Workshop on Clinical Aspects of Neutron Capture Therapy, R.G. Fairchild, V. P. Bond, and A. D. Woodhead, eds., Basic Life Sciences Series, Vol. 50, Plenum Press, New York, p. 121 (1989).CrossRefGoogle Scholar
  12. 12.
    J. R. Choi, S. D. Clement, O. K. Harling, and R. G. Zamenhof, “Neutron Capture Therapy Beams at the MIT Research Reactor.” (These Proceedings.)Google Scholar
  13. 13.
    S. D. Clement, J. R. Choi, R. G. Zamenhof, and O. K. Harling, “Monte Carlo Methods of Neutron Beam Design for Neutron Capture Therapy at the MIT Research Reactor (MTTR-II).” (These Proceedings.)Google Scholar
  14. 14.
    G. R. Wellum, R. G. Zamenhof, and E. I. Tolpin, “Boron Neutron Capture Radiation Therapy of Cerebral Gliomas: An Analysis of the Possible Use of Boron-Loaded Tumor-Specific Antibodies for the Selective Concentration of Boron in Gliomas,” Int. J. Radiat. Oncol. Biol. Phys., 8(8):1339 (1983).Google Scholar
  15. 15.
    T. Matsumoto and O. Aizawa, “Depth-Dose Evaluations and Optimization of the Irradiation Facility for Boron Neutron Capture Therapy of Brain Tumors,” Phys. Med. Biol 30(9):897 (1985).PubMedCrossRefGoogle Scholar
  16. 16.
    J. F. Briesmeister, ed., “MCNP — A General Monte Carlo Code for Neutron and Photon Transport, Version 3A,” Los Alamos National Laboratory, LA-7396-M, Rev. 2 (1986).Google Scholar
  17. 17.
    W. S. Snyder, M. R. Ford, G. G. Warner, and H. L. Fisher, Jr., “Estimates for Absorbed Fractions for Monoenergetic Photon Sources Uniformly Distributed in Various Organs of a Heterogeneous Phantom,” MIRD, J. Nucl. Med., Suppl. No. 3, Pamphlet 5, p. 47 (1969).Google Scholar
  18. 18.
    B. W. Murray, O. L. Deutsch, R. G. Zamenhof, and G. L. Brownell, “New Approaches to the Dosimetry of Boron Neutron Capture Therapy at MIT-MGH,” in Biomedical Dosimetry, IAEA, Vienna (1975).Google Scholar
  19. 19.
    O. L. Deutsch, and B. W. Murray, “Monte Carlo Dosimetry Calculation for Boron Neutron Capture Therapy in the Treatment of Brain Tumors,” Nucl. Technol., 26:320 (1975).Google Scholar
  20. 20.
    R. A. Brooks, G. DiChiro, and M. R. Keller, “Explanation of Cerebral White-Gray Contrast in Computed Tomography,” J. Comp. Assist. Tomog., 4(4):489 (1980).Google Scholar
  21. 21.
    M. A. Weissberger, R. G. Zamenhof, S. Aronow, and R. M. Neer, “Computed Tomography Scanning for the Measurement of Bone Mineral in the Human Spine,” J. Comp. Assist. Tomog., 2:253 (1978).CrossRefGoogle Scholar
  22. 22.
    E. Betz, “Cerebral Blood: Its Measurement and Regulation,” Physiological Reviews, 3: 595 (1972).Google Scholar
  23. 23.
    BNL-325, Suppl. No. 2, 6th Ed. (1988).Google Scholar
  24. 24.
    J. H. Hubbel, “Photon Mass Attenuation and Energy Absorption Coefficients from 1 KeV to 20 MeV,” Int. J. Appl. Rachat. Isot., 33:1269 (1982).CrossRefGoogle Scholar
  25. 25.
    R. S. Caswell, J. J. Coyne, and M. L. Randolph, “KERMA Factors of Elements and Compounds for Neutron Energies Below 30 MeV,” Int. J. Appl. Radiat. Isot., 33:1227 (1982).CrossRefGoogle Scholar
  26. 26.
    A. K. Asbury, R. Ojemann, and S. L. Nielsen, “Neuropathologic Study of Fourteen Cases of Malignant Brain Tumors Treated by Boron-10 Slow Neutron Capture Therapy,” J. Neuropathol. Exp. Neurol., 31:278 (1972).PubMedCrossRefGoogle Scholar
  27. 27.
    L. E. Kun, “The Brain and Spinal Cord,” in Radiation Oncology: Rationale, Techniques, Results, W. T. Moss and J. D. Cox, eds., 6th Ed., C. V. Mosby Co., St. Louis, MO, p. 597 (1989).Google Scholar
  28. 28.
    K. Kitao, “Vascular Wall Dose from Boron Neutron Capture Reaction,” in Boron-Neutron Capture Therapy for Tumors, H. Hatanaka, ed., Nishimura Co., Ltd., Niigata, Japan, p. 191 (1986).Google Scholar
  29. 29.
    Rapporteurs’ Report. (These Proceedings.)Google Scholar
  30. 30.
    R. G. Zamenhof, W. C. Schoene, G. L. Brownell, G. R. Wellum, H. Hatanaka, A. Takeuchi, and M. Shalev, “An Investigation of the Tolerance of Canine Brain to Thermal Neutron Capture Therapy.” (In Preparation.)Google Scholar

Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • R. G. Zamenhof
    • 1
  • S. D. Clement
    • 2
  • O. K. Harling
    • 2
  • J. F. Brenner
    • 1
  • D. E. Wazer
    • 1
  • H. Madoc-Jones
    • 1
  • J. C. Yanch
    • 2
  1. 1.Department of Radiation OncologyTufts — New England Medical CenterBostonUSA
  2. 2.Nuclear Reactor LaboratoryMassachusetts Institute of TechnologyCambridgeUSA

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