@article{oai:repo.qst.go.jp:00055076, author = {安藤, 興一 and 小池, 幸子 and 大平, 知佐 and 野島, 久美恵 and 古澤, 佳也 and 高井, 伸彦 and 物部, 真奈美 and 李, 玲華 and 青木, 瑞穂 and 扶川, 武志 and 山田, 滋 and 馬嶋, 秀行 and 清水, わか子 and 安藤 興一 and 小池 幸子 and 野島 久美恵 and 古澤 佳也 and 高井 伸彦 and 物部 真奈美 and 李 玲華 and 青木 瑞穂 and 扶川 武志 and 山田 滋 and 馬嶋 秀行}, journal = {放射線医学総合研究所重粒子線がん治療装置等共同利用研究報告書}, month = {Apr}, note = {The NFSa fibrosarcomas, transplanted in the right hind legs of syngeneic C3H male mice and grew to reach 8 mm in diameter, were irradiated with various LET of carbon ions. Equal doses were daily delivered for up to 6 days. Growth delay by 15 days here designated TGD15 was calculated from the tumor regrowth curve, and used as the isoeffect dose. Skin of the right hind legs was also irradiated with carbon ions. Skin reaction scores for each group were plotted against dose, and the isoeffect dose to produce score 3.0 was calculated. The RBE of carbon ions relative to Cs-137 g rays depended on the LET and the number of fractions. The RBE(skin) ranged from 1.4 to 1.7 for 20 keV/mm, from 1.5 to 2.3 for 40 keV/mm and from 2.5 to 2.9 for 80 keV/mm, respectively. The RBE(tumor) ranged from 1.3 to 1.5 for 20 keV/mm, from 1.8 to 2.3 for 40 keV/mm and from 2.4 to 3.0 for 80 keV/mm, respectively. When the therapeutic gain was designated the quotient of RBE(tumor) divided by RBE(skin), the therapeutic gain for 42 keV/mm was larger than that for 77 keV/mm whereas the therapeutic gain for 20 keV/mm was unity or less. The RBE of carbon ions depended on dose such that the RBE deceased with an increase of dose. The dose dependence of RBE for 20 keV/mm was same between the skin reaction and the tumor growth delay. However, the dose dependence of RBE for 42 and 77 keV/mm was more prominent for the skin reaction than the tumor growth delay, suggesting that a large dose per fraction would be appropriate for carbon-ion therapy.}, pages = {59--60}, title = {重粒子線による治療効果比に関する研究}, volume = {2001}, year = {2001} }