Glatting Frederik M, Hoppner Jorge, Kauczor Hans-Ulrich, Huber Peter E, Kratochwil Clemens, Giesel Frederik L, Haberkorn Uwe, Röhrich Manuel
Department of Nuclear Medicine, University Hospital Heidelberg, 69120 Heidelberg, Germany.
Clinical Cooperation Unit Molecular and Radiation Oncology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
Cancers (Basel). 2022 Oct 28;14(21):5301. doi: 10.3390/cancers14215301.
FAPI-PET is a promising imaging technique for various malignant as well as non-malignant pathologies. In a recent retrospective analysis, we evaluated the diagnostic value of repetitive early FAPI-PET-imaging with FAPI-02, FAPI-46 and FAPI-74 for malignant, inflammatory/reactive and degenerative pathologies. Here, we apply a subgroup analysis to that dataset and describe the tracer-wise uptake kinetic behavior of multiple types of FAPI-positive lesions, which are encountered frequently during clinical routine.
A total of 24 cancer patients underwent whole-body FAPI-PET scans, and images were acquired at 10, 22, 34, 46 and 58 min after the administration of 150-250 MBq of Ga-FAPI tracer molecules (eight patients each regarding FAPI-02, FAPI-46 and FAPI-74). Standardized uptake values (SUVmax and SUVmean) of healthy tissues, cancer manifestations and non-malignant lesions were measured and target-to-background ratios (TBR) versus blood and fat were calculated for all acquisition timepoints.
Differential uptake behavior over time was observed in several subclasses of malignant lesions, inflammatory/reactive lesions and degenerative lesions. These differences over time were particularly manifested in the direct comparison between the uptakes associated with pancreatic carcinoma (stable or increasing over time) and inflammatory lesions of the pancreas (markedly decreasing over time). Furthermore, marked differences were found between the three tracer variants regarding their time-dependent uptake and TBRs within different subclasses of malignant, inflammatory/reactive and degenerative pathologies.
Multiple timepoint FAPI-PET/CT is a promising innovative imaging technique that provides additional imaging information compared to single timepoint imaging. Differences in the kinetic behavior of malignant and benign pathologies can facilitate the interpretation of FAPI-positive lesions.
FAPI-PET是一种对各种恶性和非恶性病变都很有前景的成像技术。在最近的一项回顾性分析中，我们评估了使用FAPI-02、FAPI-46和FAPI-74进行重复性早期FAPI-PET成像对恶性、炎症/反应性和退行性病变的诊断价值。在此，我们对该数据集进行亚组分析，并描述多种类型FAPI阳性病变的示踪剂摄取动力学行为，这些病变在临床常规检查中经常遇到。
共有24例癌症患者接受了全身FAPI-PET扫描，并在静脉注射150-250 MBq的镓-FAPI示踪剂分子后10、22、34、46和58分钟采集图像（FAPI-02、FAPI-46和FAPI-74各8例患者）。测量健康组织、癌症表现和非恶性病变的标准化摄取值（SUVmax和SUVmean），并计算所有采集时间点相对于血液和脂肪的靶本比（TBR）。
在恶性病变、炎症/反应性病变和退行性病变的几个亚类中观察到随时间变化的不同摄取行为。这些随时间的差异尤其体现在胰腺癌相关摄取（随时间稳定或增加）与胰腺炎症性病变（随时间明显减少）的直接比较中。此外，在恶性、炎症/反应性和退行性病变的不同亚类中，三种示踪剂变体在其时间依赖性摄取和TBR方面存在显著差异。
多时间点FAPI-PET/CT是一种很有前景的创新成像技术，与单时间点成像相比可提供额外的成像信息。恶性和良性病变动力学行为的差异有助于FAPI阳性病变的解读。
