Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4, CH-4031, Basel, Switzerland.
Centre for Neuroendocrine and Endocrine Tumours, University Hospital Basel, Petersgraben 4, Basel, Switzerland.
Eur J Nucl Med Mol Imaging. 2018 Dec;45(13):2318-2327. doi: 10.1007/s00259-018-4101-5. Epub 2018 Jul 28.
Benign insulinomas are the most prevalent cause of endogenous hyperinsulinaemic hypoglycaemia (EHH) in adults, and because of their small size are difficult to localise. The purpose of the study was to test the diagnostic accuracy and clinical impact of glucagon-like peptide-1 receptor (GLP-1R) PET/CT using Ga-DOTA-exendin-4 in consecutive adult patients referred for localisation of insulinomas. The results were compared with In-DOTA-exendin-4 SPECT/CT, study-MRI and previously performed external CT and/or MRI (prior external CT/MRI).
We prospectively enrolled patients with neuroglycopenic symptoms due to EHH. GLP-1R PET/CT, SPECT/CT and study-MRI were performed in a randomised, crossover order within 3-4 days. The reference standard was surgery with histology and treatment outcome.
From January 2014 until March 2017, 52 patients were recruited. All imaging and invasive procedures before recruitment identified suspicious lesions in 46.2% of patients. GLP-1R PET/CT, SPECT/CT and study-MRI detected suspicious lesions in 78.8%, 63.5% and 63.4% of patients, respectively. In 38 patients, conclusive histology was available for final analysis. Accuracy (95% confidence interval) for PET/CT, SPECT/CT, study-MRI and prior external CT/MRI was 93.9% (87.8-97.5%), 67.5% (58.1-76.0%), 67.6% (58.0-76.1%) and 40.0% (23.9-57.9%), respectively (all P values < 0.01, except comparison of SPECT/CT and study-MRI with a P value = 1.0). Impact on clinical management was 42.3%, 32.7% and 33.3% for PET/CT, SPECT/CT and study-MRI, respectively. Percentage reading agreement was 89.5%, 75.7%, and 71.1% for PET/CT, SPECT/CT and study-MRI, respectively.
Ga-DOTA-exendin-4 PET/CT performed significantly better than In-DOTA-exendin-4 SPECT/CT and MRI in the localisation of benign insulinomas and should be considered in patients where localisation fails with CT/MRI ( ClinicalTrials.gov , NCT02127541).
良性胰岛素瘤是成人内源性高胰岛素血症低血糖症（EHH）最常见的病因，由于其体积小，难以定位。本研究的目的是测试使用 Ga-DOTA-exendin-4 在连续的成年患者中进行胰岛素瘤定位的 GLP-1R 正电子发射断层扫描（PET）/计算机断层扫描（CT）的诊断准确性和临床影响。结果与 In-DOTA-exendin-4 单光子发射计算机断层扫描（SPECT）/CT、研究性磁共振成像（MRI）和以前进行的外部 CT 和/或 MRI（以前的外部 CT/MRI）进行比较。
我们前瞻性地招募了因 EHH 而出现神经低血糖症状的患者。GLP-1R PET/CT、SPECT/CT 和研究性 MRI 以随机、交叉的方式在 3-4 天内进行。参考标准是手术、组织学和治疗结果。
从 2014 年 1 月至 2017 年 3 月，共招募了 52 名患者。在招募前的所有影像学和侵入性检查中，46.2%的患者发现可疑病变。GLP-1R PET/CT、SPECT/CT 和研究性 MRI 分别在 78.8%、63.5%和 63.4%的患者中检测到可疑病变。在 38 名患者中，最终分析提供了明确的组织学结果。PET/CT、SPECT/CT、研究性 MRI 和以前的外部 CT/MRI 的准确性（95%置信区间）分别为 93.9%（87.8-97.5%）、67.5%（58.1-76.0%）、67.6%（58.0-76.1%）和 40.0%（23.9-57.9%）（所有 P 值均<0.01，除 SPECT/CT 和研究性 MRI 之间的比较外，P 值=1.0）。PET/CT、SPECT/CT 和研究性 MRI 对临床管理的影响分别为 42.3%、32.7%和 33.3%。PET/CT、SPECT/CT 和研究性 MRI 的阅读协议百分比分别为 89.5%、75.7%和 71.1%。
与 In-DOTA-exendin-4 SPECT/CT 和 MRI 相比，Ga-DOTA-exendin-4 PET/CT 在良性胰岛素瘤的定位中表现明显更好，应考虑在 CT/MRI 定位失败的患者中使用（ClinicalTrials.gov，NCT02127541）。
