Gordon Andrew C, Lewandowski Robert J, Salem Riad, Day Delbert E, Omary Reed A, Larson Andrew C
Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago; Department of Biomedical Engineering, Northwestern University, Evanston, Illinois.
Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago.
J Vasc Interv Radiol. 2014 Mar;25(3):397-404. doi: 10.1016/j.jvir.2013.10.022. Epub 2013 Dec 6.
To test whether iron oxide (IO)-containing yttrium aluminosilicate (YAS) microparticles (MPs) can generate localized therapeutic hyperthermia (≥ 43°C) when injected intratumorally in an animal model of liver cancer and whether MP distributions could be visualized with magnetic resonance (MR) imaging.
Twenty-one Sprague-Dawley rats implanted with N1-S1 liver tumors were assigned to alternating magnetic field (AMF) exposure following intratumoral injection with IO-YAS MPs (n = 7), sham surgery (n = 7), or baseline iron quantification (n = 7). Three fiberoptic probes allowed spatial and temporal monitoring of temperatures during 24 minutes of AMF exposure. T2-weighted turbo spin-echo MR imaging was performed within 1 hour after the procedure to detect signal voids caused by IO-YAS deposition. Hematoxylin and eosin-stained pathologic slides were also obtained, and the presence of IO-YAS was evaluated with inductively coupled plasma optical emission spectroscopy.
Following AMF exposure, intratumoral temperatures after IO-YAS MP injection achieved therapeutic hyperthermia whereas those after sham surgery did not (46.6°C ± 1.3 vs 36.8°C ± 0.4; P < .0001). Within the treated group, the normal hepatic parenchyma (NHP) and rectal temperatures were 37.4°C ± 0.9 and 36.5°C ± 1.0 (P = .0809) at the conclusion of AMF exposure, respectively. A T2-weighted signal void at the tumor site was observed in all seven treated animals, and intratumoral IO-YAS was visualized on subsequent histopathologic examination in each case. The mean ratio of tumor:NHP Fe concentrations attributable to IO-YAS MPs was 108:1.
AMF exposure of intratumoral IO-YAS MPs generates localized therapeutic hyperthermia in an animal model of liver cancer. MR detectability and potential for combination brachytherapy warrants further investigation for thermoradiotherapy in liver cancer.
测试含氧化铁（IO）的钇铝硅酸盐（YAS）微粒（MPs）在肝癌动物模型中瘤内注射时能否产生局部治疗性热疗（≥43°C），以及MPs的分布能否通过磁共振（MR）成像可视化。
将21只植入N1-S1肝肿瘤的Sprague-Dawley大鼠分为三组，分别在瘤内注射IO-YAS MPs后进行交变磁场（AMF）暴露（n = 7）、假手术（n = 7）或基线铁定量（n = 7）。三个光纤探头可在AMF暴露24分钟期间进行温度的空间和时间监测。在操作后1小时内进行T2加权快速自旋回波MR成像，以检测由IO-YAS沉积引起的信号缺失。还获取了苏木精和伊红染色的病理切片，并通过电感耦合等离子体发射光谱法评估IO-YAS的存在情况。
AMF暴露后，IO-YAS MPs注射后瘤内温度达到治疗性热疗，而假手术后未达到（46.6°C±1.3对36.8°C±0.4；P <.0001）。在治疗组中，AMF暴露结束时，正常肝实质（NHP）和直肠温度分别为37.4°C±0.9和36.5°C±1.0（P = 0.0809）。在所有七只接受治疗的动物中均观察到肿瘤部位的T2加权信号缺失，并且在随后的各病例组织病理学检查中均可见瘤内IO-YAS。归因于IO-YAS MPs的肿瘤：NHP铁浓度的平均比值为108：1。
瘤内IO-YAS MPs的AMF暴露在肝癌动物模型中产生局部治疗性热疗。MR可检测性以及联合近距离放疗的潜力值得在肝癌热放疗中进一步研究。
