Department of Nuclear Medicine, Fortis Memorial Research Institute, Gurgaon, India.
Department of Nuclear Medicine, Fortis Memorial Research Institute, Gurgaon, India
J Nucl Med Technol. 2020 Mar;48(1):68-72. doi: 10.2967/jnmt.119.230516. Epub 2019 Oct 11.
Because of the excellent ability of α-particles to transfer a high amount of energy over a short tissue range, targeted α-therapy has been attracting rising numbers of nuclear medicine centers. In this study, we estimated the radiation exposure to the occupational workers with pocket dosimeters during handling of the α-emitter Bi, used for targeted α-therapy of neuroendocrine tumor and castration-resistant prostate cancer patients. The dose rates from patients at different distances and time points after injection of the therapy were also evaluated. This prospective study was done in the Department of Nuclear Medicine at Fortis Memorial Research Institute, Gurgaon, India. Twelve patients with neuroendocrine tumors or castration-resistant prostate cancer were enrolled to receive Bi-DOTATOC or Bi-prostate-specific membrane antigen therapy, respectively. Each patient received 2-3 intravenous injections of Bi-peptide, 266-362 MBq (7.2-9.8 mCi) in a single cycle over 2-3 d. The radiation exposure to nuclear medicine personnel at the chest and extremity levels was assessed for tasks such as elution, dispensing, injecting, and collecting blood samples. Radiation levels were measured at distances of 1 cm and 1 m from patients immediately after, and at 1, 2, and 4 h after, the administration of Bi-peptide. The external dose incurred at the chest level by radiopharmacists during synthesis, by physicians during injection, by technologists during imaging, and by nurses during sample collection was 2-7 μSv/procedure. The extremity dose was 1-14 μSv/procedure. The dose rate at 1 m from patients immediately after Bi-radiopharmaceutical injection was 0.02-0.03 μSv/MBq⋅h. The external radiation doses received by occupational workers involved in various procedures were far below the limit prescribed by the regulatory authority (20 mSv/y).
由于 α 粒子在短组织范围内转移大量能量的优异能力，靶向 α 疗法吸引了越来越多的核医学中心。在这项研究中，我们使用口袋剂量计估算了在处理用于神经内分泌肿瘤和去势抵抗性前列腺癌患者的靶向 α 治疗的 α 发射器 Bi 期间，职业工作人员的辐射暴露情况。还评估了在注射治疗后不同距离和时间点的患者的剂量率。这项前瞻性研究是在印度古尔冈的 Fortis Memorial Research Institute 核医学系进行的。12 名患有神经内分泌肿瘤或去势抵抗性前列腺癌的患者接受了 Bi-DOTATOC 或 Bi-前列腺特异性膜抗原治疗，每位患者接受 2-3 次静脉注射，Bi-肽 266-362MBq（7.2-9.8mCi），在 2-3 天内完成一个周期。评估了核医学工作人员在洗脱、配药、注射和采集血样等任务时胸部和四肢的辐射暴露情况。在给予 Bi-肽后立即、1 小时、2 小时和 4 小时，从患者 1cm 和 1m 处测量辐射水平。在放射性药物合成期间，放射科医师在注射期间、技师在成像期间和护士在采集样本期间，胸部水平的外照射剂量为 2-7μSv/次。四肢剂量为 1-14μSv/次。患者接受 Bi 放射性药物注射后立即在 1m 处的剂量率为 0.02-0.03μSv/MBq·h。从事各种程序的职业工作人员所接受的外部辐射剂量远低于监管机构规定的限值（20mSv/y）。
