18F-FDG PET/CT双时相显像对胃癌术后监测的临床价值

Postoperative Monitoring of Gastric Cancer with 18F-FDG PET/CT Dual Phase Imaging

目的分析18F-脱氧葡萄糖(18F-Deoxy Glucose,18F-FDG)早期显像与延迟现象在胃癌术后的监测结果,探讨双时相造影剂充盈法在胃癌术后监测的价值。方法选取2015年4月至2018年9月在内蒙古医科大学附属医院行18F-FDG PET/CT双时相显像的胃癌术后患者194例,对其资料进行回顾性分析。所有患者行常规早期扫描后,口服复方泛影葡胺混合液(15 mL泛影葡胺/150 mL水)约200~300 mL充盈胃腔后行胃局部延迟显像,应用感兴趣区测定双时相病变的最大标准摄取值(Standard Uptake Value,SUVmax),以胃镜病理活检结果为金标准,计算PET/CT双时相显像在胃癌术后复发诊断中的灵敏度、特异度、准确度、阳性预测值及阴性预测值,判断18F-FDG PET/CT双时相显像在胃癌术后监测的价值。结果病理活检结果显示117例为良性病变,77例为恶性病变。在胃充盈前,PET、CT及PET/CT三种检查方法分别与病理结果比较,差异均有统计学意义(P<0.05),而在胃充盈后,PET、CT及PET/CT三种检查方法分别与病理结果比较,与病理检查结果相当,差异均无统计学意义(P>0.05)。另外,早期时相及延迟时相,胃癌术后恶性病灶处的SUVmax与良性病灶处的SUVmax比较,差异均具有统计学意义(t=-21.723、-24.536,P均<0.05)。结论18F-FDG PET/CT双时相显像对胃癌术后复发具有较高的监测价值。

Objective To analyze the early imaging and delayed phenomenon of 18F-FDG in postoperative monitoring of gastric cancer,and to explore the value of dual phase contrast agent filling method in postoperative monitoring of gastric cancer.Methods From April 2015 to September 2018,194 patients with gastric cancer underwent 18F-FDG PET/CT dual phase imaging in the Affiliated Hospital of Inner Mongolia Medical University were selected for retrospective analysis.After routine early scanning,all patients were given about 200-300 mL of compound meglumine diatrizoate mixture(15 mL meglumine diatrizoate/150 mL water)to fill the stomach cavity,and then the gastric local delayed imaging was performed.The maximum standardized uptake value(SUVmax)of two-phase lesions was measured by the region of interest.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of PET/CT dual phase imaging in the diagnosis of postoperative recurrence of gastric cancer were calculated based on the gold standard of endoscopic pathological biopsy results,and the value of 18F-FDG PET/CT dual phase imaging in postoperative monitoring of gastric cancer was evaluated.Results Pathological biopsy results showed that 117 cases were benign lesions,77 cases were malignant lesions.Before gastric filling,the results of PET,CT and PET/CT were significantly different from pathological results(P<0.05),while after gastric filling,PET,CT and PET/CT were similar to pathological results,and the differences were not statistically significant(P>0.05).In addition,there were significant differences in SUVmax between malignant lesions and benign lesions in early and delayed phases(t=-21.723,-24.536,P<0.05).Conclusion 18F-FDG PET/CT dual phase imaging has a high value in monitoring postoperative recurrence of gastric cancer.