Chan Sheng-Chieh, Chiu Tsung-Lang, Ng Shu-Hang, Kao Hung-Wen, Tsai Sheng-Tzung, Liu Shu-Hsin
Department of Nuclear Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, 970423, Taiwan.
Department of Nuclear Medicine, School of Medicine, Tzu Chi University, Hualien, 970423, Taiwan.
Ann Nucl Med. 2025 Apr;39(4):342-352. doi: 10.1007/s12149-024-02005-4. Epub 2024 Nov 26.
This prospective study aimed to evaluate the diagnostic value of fluorine-18-labeled fluoroethyltyrosine (F-FET) positron emission tomography (PET)/computed tomography (CT) in diagnosing brain tumors within an Asian patient population.
Patients suspected of having primary or recurrent brain tumors were prospectively recruited. Each patient underwent F-FET and fluorine-18 fluorodeoxyglucose (F-FDG) PET/CT on separate days within 1 week. We calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy to compare the diagnostic performance of the two PET scans. The standardized uptake value (SUV) and tumor-to-background ratio (TBR) of the lesions were determined using static images. Additionally, time-activity curves (TACs) and time-to-peak (TTP) were generated from the dynamic PET images.
From September 2019 to December 2023, 33 subjects were enrolled for reasons including suspected brain tumors (n = 20) or suspicious glioma recurrence (n = 8) on magnetic resonance imaging (MRI) and restaging for glioma (n = 5). Among the patients with suspected brain tumors or glioma recurrence on MRI, 25% had false-positive results. F-FET PET/CT accurately identified 86% of these false positives. The sensitivity, specificity, PPV, NPV, and accuracy of visual interpretation of F-FET PET/CT were 96.2%, 85.7%, 96.2%, 85.7%, and 93.9%, respectively. The corresponding F-FDG PET/CT values were 73.1%, 71.4%, 90.5%, 41.7%, and 72.7%. F-FET PET/CT demonstrated significantly higher sensitivity and accuracy than F-FDG PET (p = 0.031 and p = 0.030, respectively). Using TBRmean as an adjunct reference index enhanced the diagnostic accuracy of F-FET PET/CT, achieving a sensitivity and NPV of 100%. Wash-out TAC or TTP < 20 min was associated with a PPV of 100% for brain tumors.
F-FET PET/CT appears to be a valuable tool for assessing brain tumors with indeterminate MRI findings in this Asian cohort. F-FET PET/CT offers benefits over F-FDG PET in differentiating brain tumors from nontumor brain lesions, particularly when using semiquantitative analysis with TBR. This study was registered on CinicalTrial.gov (NCT06563024).
本前瞻性研究旨在评估18F标记的氟代乙基酪氨酸（F-FET）正电子发射断层扫描（PET）/计算机断层扫描（CT）在亚洲患者群体中诊断脑肿瘤的价值。
前瞻性招募疑似患有原发性或复发性脑肿瘤的患者。每位患者在1周内的不同日期分别接受F-FET和18F氟代脱氧葡萄糖（F-FDG）PET/CT检查。我们计算了灵敏度、特异度、阳性预测值（PPV）、阴性预测值（NPV）和准确度，以比较两种PET扫描的诊断性能。使用静态图像确定病变的标准化摄取值（SUV）和肿瘤与本底比值（TBR）。此外，从动态PET图像生成时间-活性曲线（TAC）和达峰时间（TTP）。
2019年9月至2023年12月，33名受试者因多种原因入组，包括磁共振成像（MRI）怀疑脑肿瘤（n = 20）或胶质瘤复发可疑（n = 8）以及胶质瘤再分期（n = 5）。在MRI怀疑脑肿瘤或胶质瘤复发的患者中，25%有假阳性结果。F-FET PET/CT准确识别了其中86%的假阳性。F-FET PET/CT视觉判读的灵敏度、特异度、PPV、NPV和准确度分别为96.2%、85.7%、96.2%、85.7%和93.9%。相应的F-FDG PET/CT值分别为73.1%、71.4%、90.5%、41.7%和72.7%。F-FET PET/CT显示出比F-FDG PET显著更高的灵敏度和准确度（p分别为0.031和0.030）。使用平均TBR作为辅助参考指标可提高F-FET PET/CT的诊断准确度，灵敏度和NPV达到100%。洗脱TAC或TTP < 20分钟与脑肿瘤的PPV为100%相关。
在这个亚洲队列中，F-FET PET/CT似乎是评估MRI结果不确定的脑肿瘤的有价值工具。在区分脑肿瘤与非肿瘤性脑病变方面，F-FET PET/CT比F-FDG PET更具优势，特别是在使用TBR进行半定量分析时。本研究已在ClinicalTrial.gov注册（NCT06563024）。
