摘要
背景与目的小细胞肺癌恶性程度高,早期诊断对其预后有重要价值,目前的检查方法比较局限,传统影像学方法特异性差,而PET/CT价格昂贵,难于推广应用。小细胞肺癌属神经内分泌肿瘤,高表达生长抑素受体,是其早期进行分子影像诊断的理论基石。本实验旨在观察99mTc-octreotide在正常裸鼠体内的分布、代谢及荷人NCI-H446小细胞肺癌裸鼠模型体内显像变化,为临床小细胞肺癌早期诊断奠定基础。方法建立人小细胞肺癌的裸鼠肿瘤模型,正常裸鼠及荷瘤鼠静脉注射99mTc-octreotide显像剂后行动态及延迟显像。运用感兴趣区(region of interest,ROI)技术勾画各时相裸鼠各脏器、肿瘤(T)及肿瘤对侧对应部位(N)放射性计数,计算相应T/N比值,并建立30 min内各ROI的时间-放射性(A-T)曲线。结果 1正常裸鼠的肾脏、肝脏内99mTc-octreotide分布最多,肺部、心脏部位分布较低,头部放射性分布最少,99mTc-octreotide主要通过泌尿系统排泄;各脏器30 min内A-T曲线显示放射性分布随时间延迟呈逐渐下降趋势。25例荷瘤裸鼠的肿瘤显像均呈阳性;静脉注射99mTc-octreotide后肿瘤部位在3 h显像最清楚,整个检查时间内肝脏放射性强度明显高于肿瘤组织,肺部放射性与肿瘤部位较相近。半定量分析结果显示,静脉注射99mTc-octreotide后肿瘤组织与对侧肢体肌肉的T/N比值在0.5 h、2 h、3 h、4 h分别为.63±0.03、2.08±0.2、3.03±0.23、2.689±0.3;各时相T/N比值差异有统计学意义(F=5.69,P<0.000,);通过两两比较发现,静脉注射显像剂后3 h的T/N比值与其他各时相差异均有统计学意义(P<0.05);不同检查时间肝脏部位的放射性平均计数高于肿瘤部位,肺部的平均计数与肿瘤相近。肿瘤部位A-T曲线显示,注射99mTc-octreotide后2 min-3 min出现一过性放射性分布高峰。结论运用99mTc-octreotide作显像剂,人小细胞肺癌NCI-H446裸鼠模型具有极高的显像阳性率,且3 h肿瘤显像最清楚。
Background and objective For highly aggressive small cell lung cancer （SCLC）, early diagnosis is im-portant for its prognosis, but the current inspection methods are more limited, with poor specificity of the traditional imaging methods, and the high cost of PET/CT, difcult to popularization and application. SCLC is kind of neuroendocrine tumors, high expression of somatostatin receptors, which is the cornerstone of its early molecular imaging diagnosis. Te aim of this study is to observe the biodistribution and metabolism of 99mTc-octreotide in normal and the human SCLC bearing nude mice. Methods Dynamic and static scintigraphy at 0.5 h, 2 h, 3 h, 4 h were performed in both normal and tumor bearing nude mice afer intravenous injection of 99mTc-octreotide. Te technique of drawing region of interest （ROI） was used to obtain the aver-aged pixel counts and the activity-time （A-T） curve of brain, heart, lung, liver, kidney, tumor, respectively. Results ① Te biodistribution study in normal nude mice showed highest uptake in kidney and liver, lower in lung and heart, lowest in brain. Most 99mTc-octreotide was excreted via kidney. ② All tumors were displayed clearly at 3 h postinjection of 99mTc-octreotide. Te averaged T/N ratio at 0.5 h, 2 h, 3 h, 4 h postinjection of 99mTc-octreotide was 1.163±0.03, 2.08±0.12, 3.03±0.23, ±2.689±0.31, respectively （F=51.69, P〈0.000,1）. Te radioactivity of tumor was lower than liver, and similar with the lung. Te curve of tu-mor showed a radioactivity peak at 2 min-3 min postinjection. Conclusion 99mTc-octreotide receptor imaging on nude mice bearing SCLC shares high positive rate, especially at 3 h postinjection.
出处
《中国肺癌杂志》
CAS
CSCD
北大核心
2015年第1期1-7,共7页
Chinese Journal of Lung Cancer
关键词
99m锝
奥曲肽
小细胞肺癌
裸鼠
受体显像
Technetium
Octreotide
Small cell lung cancer
Nude mouse
Receptor imaging
