18F-Fluorodeoxyglucose positron emission tomography may not visualize radiation pneumonitis
18F-Fluorodeoxyglucose positron emission tomography may not visualize radiation pneumonitis
复制标题
18F-氟脱氧葡萄糖正电子发射断层扫描可能无法显示放射性肺炎
DOI：
10.1186/s13550-019-0571-0
复制
发表时间：
2019-12-19
期刊：
影响因子：
3.2
通讯作者：
Yue, Jinbo
中科院分区：
文献类型：
--
作者：
Guo, Meiying;Qi, Liang;Yue, Jinbo
背景放射性肺炎是放射治疗（RT）的常见和潜在致命的并发症。一些放射性肺炎患者在正电子发射断层扫描（PET）上显示氟脱氧葡萄糖（FDG）摄取增加，但其他患者则没有。放射性肺炎与F-18-FDG PET结果之间的确切关系仍存在争议。方法采用Wistar大鼠放射性肺炎模型，同时伴有放射性和模拟细菌感染。处理组（10只大鼠/组）如下：对照、仅RT、仅脂多糖（LPS）和RT+LPS。所有大鼠在RT（或假手术）后7周进行micro-PET扫描。进行组织学、免疫组织化学和生化分析以评估潜在的机制。结果放射性肺损伤大鼠于放疗后7周出现放射性肺炎。与对照组相比，LPS组（均P < 0.001）和RT+LPS组（均P < 0.001）此时的最大和平均标准化摄取值（SUVmax和SUVmean）显著增加，但仅RT组无差异（P = 0.156 SUVmax和P = 0.304 SUVmean）。RT + LPS组肺组织有氧糖酵解酶PKM 2（P < 0.001）和葡萄糖转运蛋白GLUT 1（P = 0.004）表达增加。LPS单独作用可增加PKM 2的表达（P = 0.018），而RT单独作用对PKM 2（P = 0.270）和GLUT 1（P = 0.989）无影响。结论F-18-FDG PET不能准确评估无菌性放射性肺炎，但通过LPS模拟细菌感染后可以观察到。细菌感染引起FDG摄取增加的模型的潜在机制可能是瓦尔堡效应。
Background Radiation pneumonitis is a common and potentially fatal complication of radiotherapy (RT). Some patients with radiation pneumonitis show increases in uptake of fluorodeoxyglucose (FDG) on positron emission tomography (PET), but others do not. The exact relationship between radiation pneumonitis and F-18-FDG PET findings remains controversial. Methods We used an animal model of radiation pneumonitis involving both radiation and simulated bacterial infection in Wistar rats. Treatment groups (10 rats/group) were as follows: control, RT-only, lipopolysaccharide (LPS)-only, and RT+LPS. All rats had micro-PET scans at 7 weeks after RT (or sham). Histologic, immunohistochemical, and biochemical analyses were performed to evaluate potential mechanisms. Results Irradiated rats had developed radiation pneumonitis at 7 weeks after RT based on pathology and CT scans. Maximum and mean standardized uptake values (SUVmax and SUVmean) at that time were significantly increased in the LPS group (P < 0.001 for both) and the RT+LPS group (P < 0.001 for both) relative to control, but were not different in the RT-only group (P = 0.156 SUVmax and P = 0.304 SUVmean). The combination of RT and LPS increased the expression of the aerobic glycolysis enzyme PKM2 (P < 0.001) and the glucose transporter GLUT1 (P = 0.004) in lung tissues. LPS alone increased the expression of PKM2 (P = 0.018), but RT alone did not affect PKM2 (P = 0.270) or GLUT1 (P = 0.989). Conclusions Aseptic radiation pneumonitis could not be accurately assessed by F-18-FDG PET, but was visualized after simulated bacterial infection via LPS. The underlying mechanism of the model of bacterial infection causing increased FDG uptake may be the Warburg effect.