Department of Nuclear Medicine, University Medical Centre Ljubljana, Zaloska 7, 1525, Ljubljana, Slovenia.
Department of Abdominal Surgery, University Medical Centre Ljubljana, Ljubljana, Slovenia.
Mol Imaging Biol. 2020 Feb;22(1):165-172. doi: 10.1007/s11307-019-01372-z.
Insulinomas are the most common functioning neuroendocrine neoplasms of the pancreas, typically diagnosed due to characteristic symptoms. In the vast majority, the treatment is surgical and curative, requiring accurate localization of the tumour; conventional imaging, including somatostatin receptor molecular imaging, is negative in up to 10 % of cases. Recently, labelled glucagon-like peptide receptor (GLP-1R) analogues were introduced as a sensitive diagnostic method for localization of insulinomas. The aim of this study was to assess the diagnostic accuracy of a Tc-99m-labelled GLP-1R agonist [Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4 for localization of occult insulinoma.
Eight patients (all females; age range 35-75 years) with biochemically proven insulinoma and with negative or inconclusive conventional imaging (consisting of somatostatin receptor scintigraphy, computed tomography, endoscopic ultrasound and magnetic resonance imaging) were enrolled. Whole-body single-photon emission tomography/computed tomography (SPECT/CT) imaging was performed 4 h post-injection of 740 MBq of [Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4. Surgical treatment was performed based on imaging findings. Histology of the removed lesions and biochemical and clinical symptom resolution was considered as the gold standard for analysis of the imaging results.
Focal uptake of [Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4 was found in all patients, leading to successful removal of the offending lesion and complete biochemical and symptomatic resolution. Histological analysis confirmed insulinoma in all included patients.
[Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4 SPECT/CT appears to be an excellent molecular imaging method for preoperative localization of an occult insulinoma, surpassing conventional imaging methods. If routinely available, it could be considered as a method of choice due to its favorable combination of imaging characteristics.
胰岛素瘤是胰腺最常见的功能性神经内分泌肿瘤，通常因特征性症状而诊断。在绝大多数情况下，治疗是手术和治愈性的，需要准确定位肿瘤；包括生长抑素受体分子成像在内的常规成像在多达 10%的病例中呈阴性。最近，标记的胰高血糖素样肽受体（GLP-1R）类似物被引入作为胰岛素瘤定位的敏感诊断方法。本研究旨在评估 Tc-99m 标记的 GLP-1R 激动剂 [Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4 用于隐匿性胰岛素瘤定位的诊断准确性。
纳入 8 例（均为女性；年龄 35-75 岁）经生化证实患有胰岛素瘤且常规成像（包括生长抑素受体闪烁扫描、计算机断层扫描、内镜超声和磁共振成像）呈阴性或不确定的患者。在注射 740MBq [Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4 后 4 小时进行全身单光子发射计算机断层扫描/计算机断层扫描（SPECT/CT）成像。根据成像结果进行手术治疗。切除病变的组织学和生化及临床症状缓解被认为是分析成像结果的金标准。
所有患者均发现 [Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4 的局灶性摄取，导致致病病变的成功切除和完全的生化及症状缓解。所有纳入患者的组织学分析均证实为胰岛素瘤。
[Lys(AhxHYNIC-[Tc]EDDA)NH]-exendin-4 SPECT/CT 似乎是术前隐匿性胰岛素瘤定位的一种极好的分子成像方法，优于常规成像方法。如果常规可用，由于其有利的成像特征组合，它可以被认为是一种首选方法。
