Department of Radiology, Kansai Electric Power Hospital, 2-1-7 Fukushima, Fukushima-Ku, Osaka-Shi, Osaka, 5530003, Japan.
Division of Positron Emission Tomography, Institute of Advanced Clinical Medicine, Kindai University Hospital, 377-2 Ohno-Higashi, Osakasayama, Osaka, 589-8511, Japan.
Ann Nucl Med. 2024 Nov;38(11):927-932. doi: 10.1007/s12149-024-01962-0. Epub 2024 Jul 26.
When patients administered Lu-DOTATATE are released or discharged from rooms where radiopharmaceuticals are used, the time required for release or discharge varies across patients. This study investigated whether the amount of radioactivity accumulated on In-somatostatine receptor scintigraphy (In-SRS) performed prior to treatment can predict the 1 cm dose-equivalent rate at a distance of 1 m from the patient on the day after Lu-DOTATATE administration.
Whole-body planar In-SRS images were acquired for 21 patients. Pixel values within whole-body and abdominal (35 × 25 cm) regions of interest (ROIs) were converted to radioactivity dose (MBq). The 1 cm dose-equivalent rate (µSv/h) at a distance of 1 m from the patient 18.3 ± 0.5 h after administration of Lu-DOTATATE was measured using an ionization survey meter.
The following relationships were observed between the radioactivity on In-SRS and the 1 cm dose-equivalent rate on the day after administration of Lu-DOTATATE: whole-body ROI: y = 0.16x + 5.01 (r = 0.56, p = 0.009), abdominal ROI: y = 0.27x + 5.13 (r = 0.63, p = 0.002). The regression equations indicate that patients cannot be released or discharged from the radiopharmaceutical room the day after Lu-DOTATATE administration if the whole-body and abdominal ROI doses are greater than 81 and 48 MBq, respectively, on In-SRS.
The amount of radioactivity accumulated on In-SRS may be a predictor of release criteria for patients receiving Lu-DOTATATE.
当给予 Lu-DOTATATE 的患者从使用放射性药物的房间中释放或出院时，患者的释放或出院时间各不相同。本研究旨在探讨治疗前进行的 In-somatostatin 受体闪烁显像（In-SRS）所积累的放射性活度是否可以预测 Lu-DOTATATE 给药后第一天距离患者 1 米处 1cm 剂量当量率。
对 21 例患者进行全身平面 In-SRS 图像采集。将全身和腹部（35×25cm）感兴趣区（ROI）内的像素值转换为放射性活度剂量（MBq）。在 Lu-DOTATATE 给药后 18.3±0.5h，使用离子化巡测仪测量距离患者 1m 处的 1cm 剂量当量率（µSv/h）。
Lu-DOTATATE 给药后第一天的 In-SRS 放射性活度与 1cm 剂量当量率之间存在以下关系：全身 ROI：y=0.16x+5.01（r=0.56，p=0.009），腹部 ROI：y=0.27x+5.13（r=0.63，p=0.002）。回归方程表明，如果 In-SRS 全身和腹部 ROI 剂量分别大于 81 和 48MBq，则患者不能在 Lu-DOTATATE 给药后第一天从放射性药物室中释放或出院。
接受 Lu-DOTATATE 治疗的患者的 In-SRS 积累放射性活度可能是释放标准的预测指标。
