Flux G D, Chittenden S J, Saran F, Gaze M N
Joint Department of Physics, Royal Marsden NHS Foundation Trust & Institute of Cancer Research, Sutton, Surrey, UK.
Q J Nucl Med Mol Imaging. 2011 Apr;55(2):116-25.
Metaiodobenzylguanidine (mIBG), developed 30 years ago, is taken up by tumours expressing the noradrenaline transporter. Radiolabelled with I-123 or I-131, mIBG has become a gold standard for diagnostic imaging of pediatric and adult neuroendocrine cancer. Within a few years of its clinical introduction, I-131 mIBG was found to be an effective palliative treatment with minimal toxicity that in some cases could produce a complete response. The importance of internal dosimetry for I-131 mIBG therapy has been demonstrated by a number of studies showing that absorbed doses delivered to tumours and organs-at-risk from standard and weight-based activities can vary by an order of magnitude. However, significant correlations between the whole-body absorbed dose and myelotoxicity have been demonstrated and studies based on this relationship have enabled treatments to be tailored to the individual. Ongoing developments include patient-specific treatment planning based on tumour dosimetry and cocktails of radionuclides and radiosensitisers.
间碘苄胍（mIBG）于30年前研发出来，可被表达去甲肾上腺素转运体的肿瘤摄取。用I-123或I-131进行放射性标记后，mIBG已成为儿科和成人神经内分泌癌诊断成像的金标准。在其临床应用后的几年内，I-131 mIBG被发现是一种有效的姑息治疗方法，毒性极小，在某些情况下可产生完全缓解。多项研究表明，标准活度和基于体重的活度给予肿瘤和危险器官的吸收剂量可相差一个数量级，这证明了I-131 mIBG治疗内照射剂量测定的重要性。然而，已证实全身吸收剂量与骨髓毒性之间存在显著相关性，基于这种关系的研究使治疗能够因人而异。正在进行的进展包括基于肿瘤剂量测定以及放射性核素和放射增敏剂混合物的个体化治疗计划。
