^(18)F-FDGPET延迟显像在肿瘤诊断中的价值

Value of Dual-Phase ^(18)F-FDG PET in Diagnosis of Tumor

目的探讨双时相^(18)F-FDG PET显像图像、标准摄取值(SUV)及储留指数(RI%)在恶性肿瘤诊断中的价值。方法对104例疑患恶性肿瘤者及59例体检者进行^(18)F-FDG PET全身扫描,有局灶性代谢增高的患者经饮水、进食后3h进行延迟显像,用勾划感兴趣区方法计算两次显像的SUV,并计算^(18)F-FDG的RI%。随访其手术病理结果、治疗转归及再次CT/MR检查结果,综合比较^(18)F-FDG及RI%对恶性肿瘤诊断的应用效果。结果56例患者40min显像有局灶性代谢增高病灶;经3h延迟显像后发现病灶形态发生较大改变或病灶消失,综合分析为生理性代谢增高。其余107例共发现128个可疑病灶,以在40min时SUV≥3为标准,判断恶性诊断的灵敏度、特异性、准确性分别为80.3%、90.7%、84.2%;以^(18)F-FDG在病灶中的RI%≥10%作为标准,灵敏度、特异性、准确性分别为72.8%、78.9%、80.3%。结合以上两项标准,恶性肿瘤诊断灵敏度、特异性、准确性分别为100%、98.4%、98.4%。结论3h延迟显像对肿瘤诊断有辅助作用,结合应用最大SUV及RI%两项指标可提高诊断准确率。

Objective To study the value of dual-phase ^18F -FDG PET imaging, standardized uptake value（SUV） and retention index（ RI% ） in the diagnosis of malignancy. Methods One hundred and sixty-three persons were enrolled, among them 104 persons were suspected with malignant tumor, 59 persons were physical examination. Forty minutes after injection of ^18F -FDG, a whole body scan was performed,while the delayed imaging was performed 3 h after injection. SUV was calculated with delineated ROI method for each image, and retention index （ RI% ） was also calculated. Operation,pathology therapeutic result and repeated CT/MR were follow up. The diagnostic value of SUV and RI% for malignancy was analyzed. Results Focal high metabolic loci was found. In 56 cases at 40 min image, the lesion morphology change greatly or disappeared at delay image and was considered as physiological high uptake. The remaining 107 cases were revealed 128 doubtful lesions. Take SUV ≥3 as stand, the sensitivity, speciality and accuracy of malignancy was 72.8% , 78.9% and 80.3% respectively. Take RI% ≥ 10% as standard, the sensitivity, speciality and accuracy of malignancy was 72.8% ,78.9% and 80.3%. When combining these two indexes as standard, the sensitivity, speciality and accuracy of malignancy was 100% ,98.4% and 98.4% respectively. Conclusion Combining SUV and RI% in dual-phase imaging, it can improve the accuracy in the diagnosis of malignancy.