Relative biological effectiveness (RBE) and out-of-field cell survival responses to passive scattering and pencil beam scanning proton beam deliveries
Relative biological effectiveness (RBE) and out-of-field cell survival responses to passive scattering and pencil beam scanning proton beam deliveries
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DOI：
10.1088/0031-9155/57/20/6671
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发表时间：
2012-10-21
影响因子：
3.5
通讯作者：
Prise, Kevin M.
中科院分区：
文献类型：
--
作者：
Butterworth, Karl T.;McGarry, Conor K.;Prise, Kevin M.
均匀束配置的被动散射（PS）和笔形束扫描（PBS）质子束传输技术的相对生物有效性（RBE）由克隆存活率决定。在两种递送技术的场内或场外发生的调制束配置对细胞存活的放射生物学影响是在细胞间通讯完整或物理抑制的情况下确定的。将细胞存活反应与使用线性加速器产生的 6 MV 光子束观察到的细胞存活反应进行比较。考虑到分散布拉格峰中心质子的 RBE 为 1.1，DU-145 细胞对 PS 和 PBS 或 6 MV 光子传递的质子束的存活反应没有显着差异。对于 PS 和 PBS 质子传递，观察到与 6 MV 光子观察到的显着场外效应类似，对于被动散射和笔形束扫描束，散射剂量分别为 0.05 和 0.03 Gy，细胞存活率降低至 50-60%。观察到的场外反应取决于场内和场外细胞群之间的细胞间通讯。这些数据首次证明被动和主动扫描质子束之间具有相似的 RBE，并证实场外效应可能是暴露于调制光子和质子场后细胞存活的重要决定因素
The relative biological effectiveness (RBE) of passive scattered (PS) and pencil beam scanned (PBS) proton beam delivery techniques for uniform beam configurations was determined by clonogenic survival. The radiobiological impact of modulated beam configurations on cell survival occurring in- or out-of-field for both delivery techniques was determined with intercellular communication intact or physically inhibited. Cell survival responses were compared to those observed using a 6 MV photon beam produced with a linear accelerator. DU-145 cells showed no significant difference in survival response to proton beams delivered by PS and PBS or 6 MV photons taking into account a RBE of 1.1 for protons at the centre of the spread out Bragg peak. Significant out-of-field effects similar to those observed for 6 MV photons were observed for both PS and PBS proton deliveries with cell survival decreasing to 50-60% survival for scattered doses of 0.05 and 0.03 Gy for passive scattered and pencil beam scanned beams respectively. The observed out-of-field responses were shown to be dependent on intercellular communication between the in-and out-of-field cell populations. These data demonstrate, for the first time, a similar RBE between passive and actively scanned proton beams and confirm that out-of-field effects may be important determinants of cell survival following exposure to modulated photon and proton fields