Boron neutron capture therapy: A guide to the understanding of the pathogenesis of late radiation damage to the rat spinal cord

• Published in: International journal of radiation oncology, biology, physics Vol. 28; no. 5; pp. 1107 - 1112
• Main Authors: Morris, Gerard M., Coderre, Jeffrey A., Whitehouse, Elizabeth M., Micca, Peggy, Hopewell, John W.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 30.03.1994; Elsevier
• Subjects: 550603 > Medicine > External Radiation in Therapy > (1980-); Animals; Biological and medical sciences; BIOLOGICAL EFFECTS; Biological effects of radiation; BIOLOGICAL MODELS; BIOLOGICAL RADIATION EFFECTS; Borohydrides - adverse effects; Boron neutron capture therapy; Boron Neutron Capture Therapy - adverse effects; BSH; CENTRAL NERVOUS SYSTEM; Fundamental and applied biological sciences. Psychology; Ionizing radiations; Male; MEDICINE; NERVOUS SYSTEM; NEUTRON CAPTURE THERAPY; NEUTRON THERAPY; NUCLEAR MEDICINE; Pathogenesis; RADIATION EFFECTS; RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT; RADIOLOGY; RADIOLOGY AND NUCLEAR MEDICINE; RADIOTHERAPY; Rats; Rats, Inbred F344; SIDE EFFECTS; Spinal cord; Spinal Cord - pathology; Spinal Cord - radiation effects; Sulfhydryl Compounds - adverse effects; THERAPY 560152 > Radiation Effects on Animals > Animals; Thermal neutrons; TIME DELAY; Tissues, organs and organisms biophysics; Spinal cord; Thermal neutrons; Pathogenesis; BSH; Boron neutron capture therapy; Boron compound; Rat; Rodentia; Central nervous system; Neutron capture; Radiotherapy; Neutron therapy; Pathology; Ionizing irradiation; Vertebrata; Mammalia; Animal; Radiation injury; Neutron irradiation; Biological effect
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/0360-3016(94)90484-7

Purpose : Before the commencement of new boron neutron capture therapy (BNCT) clinical trials in Europe and North America, detailed information on normal tissue tolerance is required. In this study, the pathologic effects of BNCT on the central nervous system (CNS) have been investigated using a rat spinal cord model. Methods and Materials : The neutron capture agent used was 'B enriched sodium mercaptoundecahydro-closododecaborate (BSH), at a dosage of 100 mg/kg body weight. Rats were irradiated on the thermal beam at the Brookhaven Medical Research Reactor. The large spine of vertebra T 2 was used as the lower marker of the irradiation field. Rats were irradiated with thermal neutrons alone to a maximum physical absorbed dose of 11.4 Gy, or with thermal neutrons in combination with BSH, to maximum absorbed physical doses of 5.7 Gy to the CNS parenchyma and 33.7 Gy to the blood in the vasculature of the spinal cord. An additional group of rats was irradiated with 250 kVp X rays to a single dose of 35 Gy. Spinal cord pathology was examined between 5 and 12 months after irradiation. Results : The physical dose of radiation delivered to the CNS parenchyma, using thermal neutron irradiation in the presence of BSH, was a factor of two to three lower than that delivered to the vascular endothelium, and could not account for the level of damage observed in the parenchyma. Conclusion : The histopathological observations of the present study support the hypothesis that the blood vessels, and the endothelial cells in particular, are the critical target population responsible for the lesions seen in the spinal cord after BNCr type irradiation and by inference, after more conventional irradiation modalities such as photons or fast neutrons.