Abstract：
BACKGROUND: To elucidate the role of various imaging modalities for tumor localization in ectopic ACTH Cushing\'s syndrome (EAS).
METHODS: Systematic review of the literature published between January 2015-2024 was performed. Patients (290 EAS patients, 23.8% Occult) who underwent contrast enhanced CT (CECT) and at least one PET/CT-scan (68Ga-SSTR, FDG and/or F-DOPA) were included.
RESULTS: The sensitivity for identifying EAS tumor was comparable across CECT (63.1%, n=290), SSTR-PET/CT (58.2%, n=187), and FDG-PET/CT (57.6%, n=191), but was poor for DOPA-PET/CT (30.8%, n=26). Sensitivity for detecting metastasis was also comparable across CECT (78%, n=73), SSTR-PET/CT (85.3%, n=41), and FDG-PET (73.7%, n=38). For localised lesions, sensitivity as per etiology and grade of NET were similar for three scans, with exception of Thymic NET and grade 1 NET where CECT was better than FDG PET/CT. In patients not localised on CECT, sensitivity of SSTR PET/CT was 33.3% (vs. 18.9% FDG-PET/CT) whereas for patients negative on CECT and FDG-PET, sensitivity of SSTR-PET/CT was 15%. In cases where CECT and SSTR-PET/CT failed to localize, the sensitivities of FDG-PET/CT and DOPA-PET/CT were only 5.7% (2/35) and 0% (0/9), respectively. SSTR-PET/CT has a distinct advantage with significantly lesser false positive (FP) lesions (2.6%, mostly in thyroid/or pancreas). In comparison, CECT and FDG-PET/CT had FP ∼11% (mostly in lung and/or mediastinum), most of which were negative on SSTR-PET/CT.
CONCLUSIONS: As per the current evidence, SSTR-PET/CT can be considered as the scan of choice in EAS evaluation, and further research is needed as one-fourth of the lesions remain occult.
METHODS: Systematic review of the literature published between January 2015-2024 was performed. Patients (290 EAS patients, 23.8% Occult) who underwent contrast enhanced CT (CECT) and at least one PET/CT-scan (68Ga-SSTR, FDG and/or F-DOPA) were included.
RESULTS: The sensitivity for identifying EAS tumor was comparable across CECT (63.1%, n=290), SSTR-PET/CT (58.2%, n=187), and FDG-PET/CT (57.6%, n=191), but was poor for DOPA-PET/CT (30.8%, n=26). Sensitivity for detecting metastasis was also comparable across CECT (78%, n=73), SSTR-PET/CT (85.3%, n=41), and FDG-PET (73.7%, n=38). For localised lesions, sensitivity as per etiology and grade of NET were similar for three scans, with exception of Thymic NET and grade 1 NET where CECT was better than FDG PET/CT. In patients not localised on CECT, sensitivity of SSTR PET/CT was 33.3% (vs. 18.9% FDG-PET/CT) whereas for patients negative on CECT and FDG-PET, sensitivity of SSTR-PET/CT was 15%. In cases where CECT and SSTR-PET/CT failed to localize, the sensitivities of FDG-PET/CT and DOPA-PET/CT were only 5.7% (2/35) and 0% (0/9), respectively. SSTR-PET/CT has a distinct advantage with significantly lesser false positive (FP) lesions (2.6%, mostly in thyroid/or pancreas). In comparison, CECT and FDG-PET/CT had FP ∼11% (mostly in lung and/or mediastinum), most of which were negative on SSTR-PET/CT.
CONCLUSIONS: As per the current evidence, SSTR-PET/CT can be considered as the scan of choice in EAS evaluation, and further research is needed as one-fourth of the lesions remain occult.
摘要：
背景：阐明各种成像方式在异位ACTH库欣综合征（EAS）肿瘤定位中的作用。
方法：对2015年1月至2024年间发表的文献进行系统回顾。患者（290例EAS患者，23.8%隐匿性)接受对比增强CT(CECT)和至少一次PET/CT扫描(68Ga-SSTR,包括FDG和/或F-DOPA）。
结果：识别EAS肿瘤的敏感性与CECT相当（63.1%，n=290),SSTR-PET/CT（58.2%，n=187),和FDG-PET/CT（57.6%，n=191),但DOPA-PET/CT表现不佳（30.8%，n=26）。检测转移的灵敏度在CECT中也具有可比性(78%，n=73),SSTR-PET/CT（85.3%，n=41),和FDG-PET(73.7%，n=38）。对于局部病变，根据病因和NET等级的敏感性在三次扫描中相似，除胸腺NET和1级NET外，CECT优于FDGPET/CT。在CECT未定位的患者中，SSTRPET/CT的敏感性为33.3%(vs.18.9%FDG-PET/CT)而对于CECT和FDG-PET阴性的患者，SSTR-PET/CT的敏感性为15%。如果CECT和SSTR-PET/CT未能定位，FDG-PET/CT和DOPA-PET/CT的敏感性分别仅为5.7%(2/35)和0%(0/9)。SSTR-PET/CT具有明显的优势，具有明显较少的假阳性（FP）病变（2.6％，主要在甲状腺/或胰腺中）。相比之下,CECT和FDG-PET/CT的FP~11%(主要在肺和/或纵隔)，其中大多数SSTR-PET/CT阴性。
结论：根据目前的证据，SSTR-PET/CT可以被认为是EAS评估中的首选扫描，需要进一步的研究，因为四分之一的病变仍然隐匿。
方法：对2015年1月至2024年间发表的文献进行系统回顾。患者（290例EAS患者，23.8%隐匿性)接受对比增强CT(CECT)和至少一次PET/CT扫描(68Ga-SSTR,包括FDG和/或F-DOPA）。
结果：识别EAS肿瘤的敏感性与CECT相当（63.1%，n=290),SSTR-PET/CT（58.2%，n=187),和FDG-PET/CT（57.6%，n=191),但DOPA-PET/CT表现不佳（30.8%，n=26）。检测转移的灵敏度在CECT中也具有可比性(78%，n=73),SSTR-PET/CT（85.3%，n=41),和FDG-PET(73.7%，n=38）。对于局部病变，根据病因和NET等级的敏感性在三次扫描中相似，除胸腺NET和1级NET外，CECT优于FDGPET/CT。在CECT未定位的患者中，SSTRPET/CT的敏感性为33.3%(vs.18.9%FDG-PET/CT)而对于CECT和FDG-PET阴性的患者，SSTR-PET/CT的敏感性为15%。如果CECT和SSTR-PET/CT未能定位，FDG-PET/CT和DOPA-PET/CT的敏感性分别仅为5.7%(2/35)和0%(0/9)。SSTR-PET/CT具有明显的优势，具有明显较少的假阳性（FP）病变（2.6％，主要在甲状腺/或胰腺中）。相比之下,CECT和FDG-PET/CT的FP~11%(主要在肺和/或纵隔)，其中大多数SSTR-PET/CT阴性。
结论：根据目前的证据，SSTR-PET/CT可以被认为是EAS评估中的首选扫描，需要进一步的研究，因为四分之一的病变仍然隐匿。
