目的:本研究旨在评估[18F]FAPI-42PET/CT的诊断性能,并将其与2-[18F]FDGPET/CT的诊断性能进行比较分化型甲状腺癌(DTC)患者的Tg或抗Tg抗体生化升高。
方法:作为本研究的一部分,共有42例Tg或抗Tg抗体生化升高的DTC患者接受了[18F]FAPI-42PET/CT;11在7天内额外接受2-[18F]FDGPET/CT。图像是半定量和视觉解释的,和数量,location,并记录病变的摄取值。评价[18F]FAPI-42PET/CT的诊断能力和影响[18F]FAPI-42摄取的生物标志物。此外,比较了[18F]FAPI-42和2-[18F]FDG的诊断性能和摄取,并研究了病变直径与定量参数之间的相关性。
结果:在[18F]FAPI-42PET/CT上,27例(64%)患者共检出161个病灶。FAPI阳性局部复发表现出最高的摄取强度,其次是淋巴管,其他相关部位(骨和胸膜),和肺部病变(平均SUVmax,分别为4.7、3.7、3.0和2.2;P<0.0001)。TSH的水平,Tg,和Tg-Ab不影响病变的摄取值(中位SUVmax:2.4对3.2,P=0.56;2.9对2.4,P=0.0935;2.8对2.6,P=0.0525)。使用两种方法在7例患者中总共检测到90个阳性病变。所有阳性病变显示2-[18F]FDG的摄取高于[18F]FAPI-42(SUVmax,2.6对2.1;P=0.026)。然而,在局部复发和淋巴损伤中,[18F]FAPI-42的SUVmax高于2-[18F]FDG(SUVmax,分别为4.2对2.9和3.9对3.4;P>0.05)。
结论:[18F]FAPI-42可用于检测具有Tg或抗Tg生化抗体升高的DTC患者局部复发和转移过程中的病变并反映FAP表达。在此类患者中,[18F]FAPI-42PET/CT的诊断性能与2-[18F]FDGPET/CT的诊断性能相当。
This study aimed to assess the diagnostic performance of [18F]FAPI-42 PET/CT and compare it with that of 2-[18F]FDG PET/CT in patients with differentiated thyroid cancer (DTC) with biochemical elevations in Tg or anti-Tg antibodies.
A total of 42 patients with DTC with biochemical elevations in Tg or anti-Tg antibodies underwent [18F]FAPI-42 PET/CT as part of this study; of which, 11 additionally underwent 2-[18F]FDG PET/CT within 7 days. Images were semi-quantitatively and visually interpreted, and the quantity, location, and uptake values of lesions were noted. The diagnostic capacity of [18F]FAPI-42 PET/CT and biomarkers affecting the uptake of [18F]FAPI-42 were evaluated. In addition, the diagnostic performance and uptake of [18F]FAPI-42 and 2-[18F]FDG were compared, and the correlation between lesion diameter and quantitative parameters was investigated.
A total of 161 lesions were detected in 27 (64%) patients on [18F]FAPI-42 PET/CT. FAPI-positive local recurrence showed the highest uptake intensity, followed by lymphatic, other site-associated (bone and pleura), and pulmonary lesions (mean SUVmax, 4.7 versus 3.7 versus 3.0 versus 2.2, respectively; P < 0.0001). The levels of TSH, Tg, and Tg-Ab did not affect the uptake value of lesions (median SUVmax: 2.4 versus 3.2, P = 0.56; 2.9 versus 2.4, P = 0.0935; 2.8 versus 2.6, P = 0.0525, respectively). A total of 90 positive lesions were detected in 7 patients using both modalities. All positive lesions showed statistically higher uptake of 2-[18F]FDG than that of [18F]FAPI-42 (SUVmax, 2.6 versus 2.1; P = 0.026). However, the SUVmax of [18F]FAPI-42 was higher than that of 2-[18F]FDG in local recurrences and lymphatic lesions (SUVmax, 4.2 versus 2.9 and 3.9 versus 3.4, respectively; P > 0.05).
[18F]FAPI-42 can be used for detecting lesions and reflecting FAP expression during local recurrence and metastasis in patients with DTC with biochemical elevations in Tg or anti-Tg antibodies. The diagnostic performance of [18F]FAPI-42 PET/CT is comparable with that of 2-[18F]FDG PET/CT in such patients.