摘要目的:探讨 68Ga标记成纤维细胞激活蛋白抑制剂(FAPI)PET对结直肠癌患者再分期的诊断价值及对治疗决策的影响。 方法:回顾性分析2020年6月至2021年6月在华中科技大学同济医学院附属协和医院PET中心行 68Ga-FAPI PET显像进行再分期的结直肠癌患者。PET图像由3位经验丰富的影像医师评估，以活组织检查或再次术后病理、临床及影像随访结果为金标准。比较PET和常规影像(CT/MR)的诊断价值，并评估 68Ga-FAPI PET对治疗决策的影响。采用 χ2检验、Fisher确切概率法比较组间差异。 结果:纳入33例患者，男17例，女16例，年龄(52.8±12.3)岁，其中24例患者最终诊断为复发/转移/进展。 68Ga-FAPI PET探测结直肠癌复发/转移/进展的准确性、灵敏度、特异性、阳性预测值、阴性预测值分别为93.9%(31/33)、100%(24/24)、7/9、92.3%(24/26)、7/7，其准确性、灵敏度和阴性预测值明显高于常规影像[64.5%(20/31)、56.5%(13/23)和7/17; χ2值：8.549，10.786，均 P<0.05]。与检查前临床或病理分期相比， 68Ga-FAPI PET上调了12例(50.0%，12/24)患者的分期至Ⅳ期。在 68Ga-FAPI PET诊断正确的31例患者中，22例(71.0%)的治疗方案因 68Ga-FAPI PET而改变。 结论:68Ga-FAPI PET对结直肠癌再分期具有较高的诊断效能，准确的再分期有助于进一步指导临床治疗决策。

abstractsObjective:To explore the diagnostic value of 68Ga-fibroblast activation protein inhibitor (FAPI) PET for the restaging of patients with colorectal cancer and its impact on treatment strategy. Methods:Patients with colorectal cancer who underwent 68Ga-FAPI PET imaging in the PET Center of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from June 2020 to June 2021 were retrospectively analyzed. PET images were evaluated by 3 experienced imaging physicians. Biopsy or postoperative pathology, clinical and imaging follow-up results were as the gold standard. The diagnostic value of PET was compared with conventional imaging (CT/MR), and the impact of 68Ga-FAPI PET on guiding treatment was evaluated. χ2 test and Fisher exact test were used to compare the differences between groups. Results:A total of 33 patients were included (17 males, 16 females, age (52.8±12.3) years), of which 24 were finally diagnosed as recurrence/metastases/progression. The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of 68Ga-FAPI PET in detecting recurrence/metastases/progression of colorectal cancer were 93.9%(31/33), 100%(24/24), 7/9, 92.3%(24/26) and 7/7, respectively. Its accuracy, sensitivity and negative predictive value were significantly higher than those of conventional imaging (64.5%(20/31), 56.5%(13/23) and 7/17; χ2 values: 8.549 and 10.786, all P<0.05). Compared with the clinical or pathological stage before examination, 68Ga-FAPI PET led upstaging to stage Ⅳ in 12 patients (50.0%, 12/24). Of the 31 patients who were correctly diagnosed by 68Ga-FAPI PET, the treatment regimen of 22 patients (71.0%) was changed because of 68Ga-FAPI PET imaging. Conclusion:68Ga-FAPI PET has good diagnostic performance in the restaging of colorectal cancer, which is helpful to further guide clinical treatment strategy.