重离子束在肿瘤治疗方面具有独特的物理学特性和生物学优势,临床上采用碳离子束和氖离子束治疗,都取得了很好的疗效。本文通过文献调研和理论计算,从物理学和生物学角度比较了碳、氮、氧、氟、氖等五种离子束的特点。将所有离子的Bragg峰定位在水中30 cm处时,氧离子束比碳离子束的核碎片产额更少、侧散射更小;在生物学特性方面,氧离子束也可能与其它离子束存在差异,氧增比可能更小,对肿瘤干细胞的杀伤力更强,有可能作为新一代肿瘤放疗用束流。
Heavy ions have been successfully used for tumor therapy and achieved outstanding clinical outcome due to its unique physical and biological characteristics. This paper compared the characteristics of carbon, nitrogen, oxygen, fluorine and neon beams both physically and biologically basing on published literatures and theoretical simulation. When we locate the Bragg peaks at 30 cm far from their entrance into water, oxygen ions induce less fragments and smaller lateral straggling. We take from granted that oxygen ions have lower oxygen enhancement ratio (OER) and stronger ability in killing cancer stem cells. Therefore, it is possible to apply for oxygen ions as next generation of heavy ion tumor radiotherapy.