Nuclear Medicine and PET, Uppsala University, Uppsala, Sweden.
J Nucl Med. 2013 Oct;54(10):1755-9. doi: 10.2967/jnumed.113.120600. Epub 2013 Aug 8.
(68)Ga-DOTATOC and (68)Ga-DOTATATE are 2 radiolabeled somatostatin analogs for in vivo diagnosis of neuroendocrine tumors with PET. The aim of the present work was to measure their comparative biodistribution and radiation dosimetry.
Ten patients diagnosed with neuroendocrine tumors were included. Each patient underwent a 45-min dynamic and 3 whole-body PET/CT scans at 1, 2, and 3 h after injection of each tracer on consecutive days. Absorbed doses were calculated using OLINDA/EXM 1.1.
Data from 9 patients could be included in the analysis. Of the major organs, the highest uptake at 1, 2, and 3 h after injection was observed in the spleen, followed by kidneys and liver. For both tracers, the highest absorbed organ doses were seen in the spleen and urinary bladder wall, followed by kidney, adrenals, and liver. The absorbed doses to the liver and gallbladder wall were slightly but significantly higher for (68)Ga-DOTATATE. The total effective dose was 0.021 ± 0.003 mSv/MBq for both tracers.
The effective dose for a typical 100-MBq administration of (68)Ga-DOTATATE and (68)Ga-DOTATOC is 2.1 mSv for both tracers. Therefore, from a radiation dosimetry point of view, there is no preference for either tracer for PET/CT evaluation of somatostatin receptor-expressing tumors.
（68）Ga-DOTATOC 和（68）Ga-DOTATATE 是两种用于正电子发射断层扫描（PET）体内诊断神经内分泌肿瘤的放射性标记生长抑素类似物。本研究旨在测量它们的比较生物分布和辐射剂量学。
纳入 10 例诊断为神经内分泌肿瘤的患者。每位患者在连续 2 天内，分别在注射每种示踪剂后 1、2 和 3 小时进行 45 分钟的动态和 3 次全身 PET/CT 扫描。使用 OLINDA/EXM 1.1 计算吸收剂量。
9 例患者的数据可纳入分析。在注射后 1、2 和 3 小时，主要器官中摄取最高的是脾脏，其次是肾脏和肝脏。对于两种示踪剂，脾和膀胱壁的吸收器官剂量最高，其次是肾脏、肾上腺和肝脏。（68）Ga-DOTATATE 引起的肝脏和胆囊壁吸收剂量略高，但有统计学意义。肝脏和胆囊壁的总有效剂量分别为 0.021±0.003 mSv/MBq。
对于典型的 100 MBq（68）Ga-DOTATATE 和（68）Ga-DOTATOC 给药，两种示踪剂的有效剂量均为 2.1 mSv。因此，从辐射剂量学的角度来看，对于评估表达生长抑素受体的肿瘤的 PET/CT，两种示踪剂均无偏好。
