The effects of boron neutron capture irradiation on oral mucosa: evaluation using a rat tongue model

Citation
Ja. Coderre et al., The effects of boron neutron capture irradiation on oral mucosa: evaluation using a rat tongue model, RADIAT RES, 152(2), 1999, pp. 113-118
Citations number
36
Categorie Soggetti
Experimental Biology
Journal title
RADIATION RESEARCH
ISSN journal
00337587 → ACNP
Volume
152
Issue
2
Year of publication
1999
Pages
113 - 118
Database
ISI
SICI code
0033-7587(199908)152:2<113:TEOBNC>2.0.ZU;2-U
Abstract
The ventral surface of the tongue of male Fisher 344 rats was used to evalu ate the response of oral mucosa to boron neutron capture irradiation. Three hours after i.p. injection of 700 mg/kg of the boron delivery agent p-boro nophenylalanine (BPA), the boron concentrations in blood and tongue mucosal epithelium were approximately 21 and 23 mu g B-10/g, respectively. The dos es required to produce a 50% incidence of ulceration with X rays, the Brook haven Medical Research Reactor thermal neutron beam alone, or the thermal n eutron beam in the presence of BPA were 13.4 +/- 0.2, 4.2 +/- 0.1, and 3.0 +/- 0.1 Gy, respectively. Ulceration of the tongue was evident by 6 to 7 da ys after irradiation, irrespective of the irradiation modality; healing was related to dose and was relatively rapid (less than or equal to 19 days). Compared to 100 kVp X rays, the relative biological effectiveness factors w ere 3.2 for the thermal neutron beam and 4.9 for the products of the boron neutron capture reaction, B-10(n,alpha)Li-7. Oral mucosa is highly sensitiv e to BPA-mediated BNC irradiation and could be a dose-limiting normal tissu e in BNCT of brain tumors, or if BPA-based BNCT is applied to the treatment of head and neck tumors. (C) 1999 by Radiation Research Society.