Potential of using cerium oxide nanoparticles for protecting healthy tissue during accelerated partial breast irradiation (APBI).
Potential of using cerium oxide nanoparticles for protecting healthy tissue during accelerated partial breast irradiation (APBI).
复制标题
DOI：
10.1016/j.ejmp.2016.03.014
复制
发表时间：
2016-04
期刊：
影响因子：
--
通讯作者：
Ngwa W
中科院分区：
文献类型：
--
作者：
Ouyang Z;Mainali MK;Sinha N;Strack G;Altundal Y;Hao Y;Winningham TA;Sajo E;Celli J;Ngwa W
本研究的目的是探讨在加速部分乳房照射（APBI）中使用氧化铈纳米颗粒（CONPs）作为自由基清除剂保护正常组织的可行性。我们假设CONPs可以通过可降解涂层从常规使用的APBI球囊涂抹器中缓慢释放，并在APBI期间保护乳房肿瘤切除腔边缘的正常组织。为了评估这种方法的可行性，我们分析计算了保护正常乳腺组织免受活性氧（ROS）侵害所需的CONPs初始浓度，以及颗粒扩散到距离乳房肿瘤切除壁不同距离所需的时间。考虑到铈具有高原子序数，我们考虑到由于与放疗光子的光电相互作用而可能发生的无意剂量增强。为了防止典型的3.4 Gy乳腺肿瘤治疗，需要5ng -g−1的CONPs来清除羟基自由基和过氧化氢。使用2nm大小的NPs，初始浓度为1mg -g−1，我们发现需要2 - 10天的扩散才能在距离肿瘤切除壁1 - 2cm的区域获得所需的CONPs浓度。在此条件下产生的剂量增强因子（DEF）小于1.01。我们的研究结果预测，在APBI期间，使用一种新的设计，在球囊涂抹器上涂覆NPs，以持续/可控地从乳房肿瘤切除术腔内原位释放，CONPs可以用于放射防护。
The purpose of this study is to investigate the feasibility of using cerium oxide nanoparticles (CONPs) as radical scavengers during accelerated partial breast irradiation (APBI) to protect normal tissue. We hypothesize that CONPs can be slowly released from the routinely used APBI balloon applicators—via a degradable coating—and protect the normal tissue on the border of the lumpectomy cavity over the duration of APBI. To assess the feasibility of this approach, we analytically calculated the initial concentration of CONPs required to protect normal breast tissue from reactive oxygen species (ROS) and the time required for the particles to diffuse to various distances from the lumpectomy wall. Given that cerium has a high atomic number, we took into account the possible inadvertent dose enhancement that could occur due to the photoelectric interactions with radiotherapy photons. To protect against a typical MammoSite treatment fraction of 3.4 Gy, 5 ng-g−1 of CONPs is required to scavenge hydroxyl radicals and hydrogen peroxide. Using 2 nm sized NPs, with an initial concentration of 1 mg-g−1, we found that 2–10 days of diffusion is required to obtain desired concentrations of CONPs in regions 1–2 cm away from the lumpectomy wall. The resultant dose enhancement factor (DEF) is less than 1.01 under such conditions. Our results predict that CONPs can be employed for radioprotection during APBI using a new design in which balloon applicators are coated with the NPs for sustained/controlled in-situ release from within the lumpectomy cavity.