^(18)F-FDG PET/MRI与PET/CT在肾细胞癌原发灶与转移灶诊断中的对比研究

Comparative study of^(18)F-FDG PET/MRI and^(18)F-FDG PET/CT in the diagnosis of renal cell carcinoma

目的探讨^(18)F-脱氧葡萄糖(FDG)正电子发射体层摄影(PET)/MRI在诊断肾细胞癌原发灶及转移灶中的应用价值。方法横断面研究。纳入2018年3月—2023年4月于武汉大学人民医院经组织学病理确诊的68例肾细胞癌患者临床资料。患者均于同一天先后行全身^(18)F-FDG PET/CT及MRI检查。由2名阅片者观察PET检出的肾细胞癌阳性病灶,包括原发灶及转移灶,在相应的^(18)F-FDG PET/CT和PET/MRI图像上评价清晰度并比较PET阳性病灶的清晰度评分,通过病灶诊断信心评分结果来评价^(18)F-FDG PET/CT或^(18)F-FDG PET/MRI对肾细胞癌的诊断信心评分。结果68例肾癌患者中,结合早期及延迟显像,58例患者^(18)F-FDG PET/CT和^(18)F-FDG PET/MRI检出相同数量阳性病灶150个,其中原发灶共58个、淋巴结转移灶44个、肝转移灶28个及骨转移灶20个,PET阳性病灶检出率为85.29%(58/68)。^(18)F-FDG PET/CT原发灶清晰度评分为[3.00(2.00,3.25)分],低于^(18)F-FDG PET/MRI T_(1)加权像(T_(1)WI)的[4.00(3.00,4.00)分]、T_(2)加权像(T_(2)WI)的[4.00(4.00,4.00)分]及弥散加权成像(DWI)的[4.00(4.00,4.00)分],差异均有统计学意义(Z=4.91、5.78、5.97,P值均<0.001)。^(18)F-FDG PET/MRI T_(1)WI、T_(2)WI、DWI对肝转移灶的清晰度评分为[3.00(3.00,4.00)]、[4.00(3.00,4.00)]、[4.00(4.00,4.00)],均优于^(18)F-FDG PET/CT清晰度评分[2.50(1.00,3.00)],差异均有统计学意义(Z=3.86、3.76、3.96,P值均<0.001)。^(18)F-FDG PET/MRI T_(1)WI、T_(2)WI、DWI对骨转移灶的清晰度评分分别为[3.00(3.00,4.00)]、[4.00(3.00,4.00)]、[4.00(4.00,4.00)],均优于^(18)F-FDG PET/CT[2.00(1.00,3.00)],差异均有统计学意义(Z=3.37、3.32、3.55,P值均<0.001)。对于淋巴结转移灶,^(18)F-FDG PET/MRI DWI清晰度评分[3.50(3.00,4.00)]高于^(18)F-FDG PET/CT[3.00(3.00,4.00)],差异有统计学意义(Z=2.44,P=0.014)。68例患者中阅片人对^(18)F-FDG PET/MRI的诊断信心评分[2.00(2.00,2.00)分]高于^(18)F-FDG PET/CT[1.00(1.00,1.00)分],差异有统计学意义(Z=4.47,P<0.001)。结论^(18)F-FDG PET/CT和^(18)F-FDG PET/MRI对PET阳性病灶的检出率无差异,但后者可提供更好的病灶清晰度和更高的诊断信心评分,且对淋巴结、肝脏及骨转移的显示优于^(18)F-FDG PET/CT。

Objective This study aims to investigate the diagnostic value of^(18)F-fluorodeoxyglucose(FDG)positron emission tomography(PET)and magnetic resonance imaging(MRI)in primary lesions and metastases of renal carcinoma by comparing the overall detection rate,lesion conspicuity,and reader confidence of^(18)F-FDG PET and computed tomography(CT)with hetero-computer fused^(18)F-FDG PET/MRI.Methods A cross-sectional study was conducted by retrospectively analyzing 68 patients with renal carcinoma diagnosed by histological pathology at the People's Hospital of Wuhan University from March 2018 to April 2023.All patients underwent whole-body^(18)F-FDG PET/CT and all-machine fusion^(18)F-FDG PET/MR examinations on the same day.Two readers observed PET-positive lesions,including primary and metastatic lesions,and evaluated and compared the clarity of PET-positive lesions on corresponding^(18)F-FDG PET/CT and PET/MRI images.The diagnostic confidence score was used to evaluate the diagnostic rate of^(18)F-FDG PET/CT or^(18)F-FDG PET/MRI in renal cell carcinoma.Results Sixty-eight patients with renal carcinoma,by combining early and delayed imaging,^(18)F-FDG PET/CT and^(18)F-FDG PET/MRI detected the same number of positive lesions,including 58 primary lesions,44 lymph node metastasis,28 liver metastases,and 20 bone metastases.The^(18)F-FDG PET/CT primary focal clarity score was[3.00(2.00,3.25)points],which was lower than those of^(18)F-FDG PET/MRI T_(1)weighted image(T_(1)WI)[4.00(3.00,4.00)points],T_(2)weighted image(T_(2)WI)[4.00(4.00,4.00)points]and diffusion weighted image(DWI)[4.00(4.00,4.00)points],and the differences were statistically significant(Z=4.91,5.78,5.97;all P values<0.001).The resolution scores of^(18)F-FDG PET/MRI T_(1)WI,T_(2)WI,and DWI for hepatic metastasis were[3.00(3.00,4.00)],[4.00(3.00,4.00)],and[4.00(4.00,4.00)],respectively.All of them were better than the^(18)F-FDG PET/CT resolution score of[2.50(1.00,3.00)],and the difference was statistically significant(Z=3.86,3.76,3.96;all P values<0.05).For bone metastases,the articulation scores of^(18)F-FDG PET/MRI T_(1)WI,T_(2)WI and DWI were[3.00(3.00,4.00)],[4.00(3.00,4.00)],and[4.00(4.00,4.00)],which were better than that of^(18)F-FDG PET/CT[2.00(1.00,3.00)],and the difference was statistically significant(Z=3.37,3.32,3.55;all P values<0.05).For lymph node metastasis,the resolution score of^(18)F-FDG PET/MRI DWI[3.50(3.00,4.00)]was higher than that of^(18)F-FDG PET/CT[3.00(3.00,4.00)],and the difference was statistically significant(Z=2.44,P=0.014).Among the 68 patients,the diagnostic confidence score of^(18)F-FDG PET/MRI[2.00(2.00,2.00)]was significantly higher than that of^(18)F-FDG PET/CT[1.00(1.00,1.00)],and the difference was statistically significant(Z=4.47,P<0.001).Conclusion No difference was found in the detection rate of PET-positive lesions between^(18)F-FDG PET/CT and^(18)F-FDG PET/MRI,but the latter provided better focal clarity and higher diagnostic confidence scores.^(18)F-FDG PET/MRI is better than^(18)F-FDG PET/CT in displaying lymph node,liver,and bone metastases.