Yadav Divya, Ballal Sanjana, Yadav Madhav Prasad, Tripathi Madhavi, Roesch Frank, Bal Chandrasekhar
Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, 110029, India.
Institute of Nuclear Chemistry, Johannes Gutenberg University Mainz, Mainz, Germany.
Eur J Nucl Med Mol Imaging. 2020 Apr;47(4):860-869. doi: 10.1007/s00259-019-04611-1. Epub 2019 Nov 22.
Recently, the new hybrid chelator DATA (6-amino-1,4-diazepine-triacetate) has been introduced, which has the advantage of high yield and radiolabelling of DATA-based octreotide derivative (TOC) at room temperature in contrast to tetraazacyclododecane-1,4,7,10-tetraacetate (DOTA) that needs 95 °C for effective labelling. However, the diagnostic potential of DATA-TOC has not been studied with other chelators in humans. The aim of this study was to compare the diagnostic efficacy of [Ga]Ga-DATA-TOC with [Ga]Ga-DOTA-NOC (which is the current standard for imaging neuroendocrine tumours (NET)) in patients of gastroenteropancreatic neuroendocrine tumours (GEP-NETs).
Fifty patients (thirty-one males and nineteen females) with biopsy-proven GEP-NETs were included in the study. Patients age ranged from 14 to 75 years (mean 46.11 years). All patients underwent two PET studies with [Ga]Ga-DATA-TOC and [Ga]Ga-DOTA-NOC. Images were evaluated visually and semi-quantitatively using maximum standardized uptake values (SUVmax) of tumour, mediastinum and liver. Tumour-to-liver (T/L) and tumour-to-mediastinum (T/M) SUVmax ratios were computed. For the purpose of comparison, patient-wise as well as lesion-wise analysis was carried out. The nonparametric-related samples Wilcoxon signed-rank test was used for comparison of the SUVmax values and ratios.
On visual evaluation, the biodistribution and image quality of [Ga]Ga-DATA-TOC was similar to [Ga]Ga-DOTA-NOC. Physiological liver uptake was lower in [Ga]Ga-DATA-TOC as compared with [Ga]Ga-DOTA-NOC, 7.65 ± 5.37 vs 8.94 ± 5.95 (p = 0.009), respectively. On a patient-wise analysis, both [Ga]Ga-DATA-TOC and [Ga]Ga-DOTA-NOC were lesion-positive in the 44 patients (88%) and were negative in the 6 patients (12%). On a lesion-based analysis, [Ga]Ga-DATA-TOC had 98.6% concordance with [Ga]Ga-DOTA-NOC (232 out of 235 lesions detected). The target tumour SUVmax on [Ga]Ga-DATA-TOC and [Ga]Ga-DOTA-NOC were 36.63 ± 32.24 and 40.82 ± 36.89, respectively (p = 0.097). The T/L SUVmax ratios were not significantly different (5.99 ± 5.52 vs 5.67 ± 4.96, p = 0.77).
[Ga]Ga-DATA-TOC PET/CT imaging produced results that were comparable with [Ga]Ga-DOTA-NOC. It, thus, has potential utility as an effective and safe alternative to Ga-DOTA-NOC with the added benefit of ease, cost-effective and improved yield of instant kit-type synthesis.
最近，新型混合螯合剂DATA（6-氨基-1,4-二氮杂环庚烷-三乙酸）已被引入，与需要95℃进行有效标记的四氮杂环十二烷-1,4,7,10-四乙酸（DOTA）相比，它具有在室温下高产率和放射性标记基于DATA的奥曲肽衍生物（TOC）的优势。然而，尚未在人体中与其他螯合剂一起研究DATA-TOC的诊断潜力。本研究的目的是比较[Ga]Ga-DATA-TOC与[Ga]Ga-DOTA-NOC（这是目前用于成像神经内分泌肿瘤（NET）的标准）在胃肠胰神经内分泌肿瘤（GEP-NETs）患者中的诊断效果。
本研究纳入了50例经活检证实为GEP-NETs的患者（31例男性和19例女性）。患者年龄在14至75岁之间（平均46.11岁）。所有患者均接受了两次PET检查，分别使用[Ga]Ga-DATA-TOC和[Ga]Ga-DOTA-NOC。使用肿瘤、纵隔和肝脏的最大标准化摄取值（SUVmax）对图像进行视觉和半定量评估。计算肿瘤与肝脏（T/L）以及肿瘤与纵隔（T/M）的SUVmax比值。为了进行比较，进行了患者层面以及病灶层面的分析。使用非参数相关样本Wilcoxon符号秩检验来比较SUVmax值和比值。
在视觉评估中，[Ga]Ga-DATA-TOC的生物分布和图像质量与[Ga]Ga-DOTA-NOC相似。与[Ga]Ga-DOTA-NOC相比，[Ga]Ga-DATA-TOC的生理性肝脏摄取较低，分别为7.65±5.37和8.94±5.95（p = 0.009）。在患者层面分析中，44例患者（88%）的[Ga]Ga-DATA-TOC和[Ga]Ga-DOTA-NOC均显示病灶阳性，6例患者（12%）均为阴性。在病灶层面分析中，[Ga]Ga-DATA-TOC与[Ga]Ga-DOTA-NOC的一致性为98.6%（在检测到的235个病灶中，有232个一致）。[Ga]Ga-DATA-TOC和[Ga]Ga-DOTA-NOC上的目标肿瘤SUVmax分别为36.63±32.24和40.82±36.89（p = 0.097）。T/L SUVmax比值无显著差异（5.99±5.52对5.67±4.96，p = 0.77）。
[Ga]Ga-DATA-TOC PET/CT成像产生的结果与[Ga]Ga-DOTA-NOC相当。因此，它有潜力作为Ga-DOTA-NOC的有效且安全的替代方案，还具有操作简便、成本效益高以及即时试剂盒型合成产率提高的额外优势。
