Precise anatomic localization of insulinomas is crucial for surgical treatment. Current routine noninvasive imaging techniques, including CT, MRI, and ⁶⁸Ga-DOTA-somatostatin analog (DOTA-SSA) PET/CT, have limited sensitivity. Endoscopic ultrasound is highly sensitive but invasive. In this prospective multicenter study, we compared the diagnostic accuracy of ⁶⁸Ga-NODAGA-exendin-4 (exendin) PET/CT with all routine imaging procedures for the localization of insulinomas. Methods: Sixty-nine adults with biochemically proven adult endogenous hyperinsulinemic hypoglycemia underwent exendin PET/CT and current routine imaging. Images were evaluated in a clinical reading and in an expert reading. Image quality was determined by quantitative analysis. Results: Based on clinical readings, the accuracy of exendin PET/CT (94.4%; 95% CI, 84.6%–98.8%) was greater than that of DOTA-SSA PET/CT (64.8%; 95% CI, 50.6%–77.3%), contrast-enhanced CT/contrast-enhanced diffusion-weighted imaging-MRI (83.3%; 95% CI, 70.7%–92.1%), and endoscopic ultrasound (82.8%; 95% CI, 64.1%–94.1%). In 13% of patients, a correct diagnosis was only reached after exendin PET/CT. Interobserver agreement between readings was higher for exendin PET/CT than for DOTA-SSA PET/CT and contrast-enhanced CT/contrast-enhanced diffusion-weighted imaging-MRI (Cohen , 1.0 vs. 0.5 and 0.55). Exendin PET/CT provided a higher insulinoma-to-background ratio (15.3 ± 6.7 vs. 5.2 ± 3.0) and contrast-to-noise ratio (22.6 ± 11.1 vs. 5.1 ± 3.7) than did DOTA-SSA PET/CT. Conclusion: This study demonstrates the superiority of exendin PET/CT in a unique prospective comparison to all current routine imaging modalities for preoperative localization of benign insulinomas, providing the level of evidence needed for clinical implementation.

胰岛素瘤的精确解剖定位对于手术治疗至关重要。目前的常规无创成像技术，包括 CT、MRI 和 ⁶⁸Ga-DOTA-somatostatin 类似物 （DOTA-SSA） PET/CT，敏感性有限。超声内镜检查具有高度敏感性但侵入性。在这项前瞻性多中心研究中，我们比较了 ⁶⁸Ga-NODAGA-exendin-4 （exendin） PET/CT 与所有常规影像学检查程序对胰岛素瘤定位的诊断准确性。方法：69 例经生化证实的成人内源性高胰岛素血症性低血糖成人接受了 exendin PET/CT 和目前的常规影像学检查。在临床阅读和专家阅读中对图像进行了评估。通过定量分析确定图像质量。结果：根据临床读数，exendin PET/CT （94.4%;95% CI，84.6%–98.8%） 的准确性高于 DOTA-SSA PET/CT （64.8%;95% CI，50.6%–77.3%）、对比增强 CT/对比增强弥散加权成像-MRI （83.3%;95% CI，70.7%–92.1%） 和超声内窥镜 （82.8%;95% CI，64.1%–94.1%）。在 13% 的患者中，只有在 exendin PET/CT 后才能做出正确诊断。exendin PET/CT 读数之间的观察者间一致性高于 DOTA-SSA PET/CT 和对比增强 CT/对比增强弥散加权成像-MRI （Cohen ， 1.0 vs. 0.5 和 0.55）。与 DOTA-SSA PET/CT 相比，Exendin PET/CT 提供了更高的胰岛素瘤背景比 （15.3 ± 6.7 vs. 5.2 ± 3.0） 和对比噪声比 （22.6 ± 11.1 vs. 5.1 ± 3.7）。 结论：本研究证明了 exendin PET/CT 在与当前所有常规成像方式在良性胰岛素瘤术前定位方面的独特前瞻性比较中具有优势，为临床实施提供了所需的证据水平。