Alan Selçuk Nalan, Beydağı Gamze, Akçay Kaan, Demirci Emre, Görmez Ayşegül, Öven Bala Başak, Çelik Serkan, Şen Fatma, Kapar Özge, Kabasakal Levent
Yeditepe University Faculty of Medicine, Department of Nuclear Medicine, İstanbul, Türkiye.
University of Missouri Faculty of Medicine, Department of Radiology, Missouri, USA.
Mol Imaging Radionucl Ther. 2025 Feb 7;34(1):31-37. doi: 10.4274/mirt.galenos.2024.50470.
This study aimed to evaluate the potential efficacy of Ga-fibroblast activation protein inhibitor (FAPi) positron emission tomography/computed tomography (PET/CT) for detecting, staging, and restaging digestive system malignancies that are F-fluorodeoxyglucose (F-FDG) negative or show equivocal F-FDG uptake.
We conducted a prospective analysis of 30 patients with pathologically confirmed primary tumors or metastases of the digestive system. Participants underwent Ga-FAPi PET/CT and F-FDG PET/CT imaging for staging or restaging purposes within the same week. The efficacy of Ga-FAPi PET/CT was assessed by comparing its ability to detect lesions and influence disease staging with that of F-FDG PET/CT.
Ga-FAPi PET/CT imaging was performed in 30 patients with F-FDG-negative or indeterminate lesions. Of the 30 patients, 23 had gastric cancer and 7 had colorectal cancer. Among all patients, histopathological diagnosis of signet ring cell carcinoma was present in 15 (50%) patients. Primary tumor or local recurrence was detected in 19 (63%) patients, lymph node metastasis in 8 (27%) patients, visceral metastasis in 4 (13%) patients, peritoneal metastasis in 14 (47%) patients, and bone metastasis in 3 (10%) patients on Ga-FAPi PET/CT images. All patients underwent histopathological confirmation on Ga-FAPi PET/CT images. The disease stage was upgraded in 20 patients (67%) after Ga-FAPi PET/CT imaging. Of the 20 patients, 12 had no evidence of recurrence or metastasis on F-FDG PET/CT.
Based on our study, Ga-FAPi PET/CT alters the disease stage in the majority of gastrointestinal malignancies with negative or equivocal F-FDG PET/CT findings. Ga-FAPi PET/CT appears to be effective in both staging and restaging of gastrointestinal malignancies, such as signet-ring cell carcinomas of the stomach that frequently show low F-FDG -avidity.
本研究旨在评估镓-成纤维细胞活化蛋白抑制剂（FAPi）正电子发射断层扫描/计算机断层扫描（PET/CT）对检测、分期及重新分期氟代脱氧葡萄糖（F-FDG）阴性或F-FDG摄取情况不明确的消化系统恶性肿瘤的潜在疗效。
我们对30例经病理证实为消化系统原发性肿瘤或转移瘤的患者进行了前瞻性分析。参与者在同一周内接受镓-FAPi PET/CT和F-FDG PET/CT成像以进行分期或重新分期。通过比较镓-FAPi PET/CT与F-FDG PET/CT检测病变及影响疾病分期的能力来评估镓-FAPi PET/CT的疗效。
对30例F-FDG阴性或不明确病变的患者进行了镓-FAPi PET/CT成像。30例患者中，23例患有胃癌，7例患有结直肠癌。所有患者中，15例（50%）为印戒细胞癌组织病理学诊断。镓-FAPi PET/CT图像上，19例（63%）患者检测到原发性肿瘤或局部复发，8例（27%）患者有淋巴结转移，4例（13%）患者有内脏转移，14例（47%）患者有腹膜转移，3例（10%）患者有骨转移。所有患者的镓-FAPi PET/CT图像均经组织病理学证实。镓-FAPi PET/CT成像后，20例患者（67%）疾病分期上调。在这20例患者中，12例在F-FDG PET/CT上无复发或转移证据。
基于我们的研究，镓-FAPi PET/CT改变了大多数F-FDG PET/CT结果为阴性或不明确的胃肠道恶性肿瘤的疾病分期。镓-FAPi PET/CT在胃肠道恶性肿瘤（如经常表现为低F-FDG摄取的胃印戒细胞癌）的分期和重新分期中似乎都是有效的。
