PET-CT在肾上腺转移瘤诊断中的应用价值

目的 探讨18F-FDG PET-CT对肾上腺转移瘤的诊断价值.方法 对88例经病理或临床随访确诊的肾上腺转移瘤及良性病变的患者行18F-FDG PET-CT检查,分别测量肾上腺病灶（共107个）的大小（短径）、CT值及最大标准摄取值（SUVmax）,采用t检验、x 2检验及Pearson相关性检验对各组数据进行统计学分析,采用受试者工作特征曲线（ROC曲线）分析确定CT值及SUVmax区分肾上腺转移瘤与良性病变的最佳临界点.结果 107个病灶中,最终确诊73个为肾上腺转移瘤,34个为良性病变,肾上腺转移瘤与良性病变病灶的大小分别为（2.17± 1.14）cm、（1.76±1.00）cm（t=1.817,P=0.072）;CT值分别为（29.65±10.29） Hu、（14.83±14.42） Hu（t=5.389,P=0.000）;SUVmax分别为9.28±5.33、2.81±1.14（t=9.890,P=0.000）.肾上腺转移瘤的大小、CT值与SUVmax均存在正相关性（r=0.620,P=0.000;r=0.561,P=0.000）.肾上腺转移瘤左右侧分布比例为：左侧58.2％（32/55）,右侧9.1％（5/55）,差异有统计学意义（x2=29.689,P=0.000）.ROC曲线分析示,以SUVmax＞ 4.1且CT值＞20 Hu作为诊断标准,则敏感度、特异度、准确度、阳性预测值及阴性预测值分别为91.3 ％（63/69）、94.7％（36/38）、92.5％（99/107）、96.9％（63/65）和85.7％（36/42）.结论18F-FDG PET-CT对肾上腺转移瘤的诊断具有较高的敏感性、特异性及准确性;以SUVmax＞4.1且CT值＞20 HU作为诊断标准,可较好地诊断出肾上腺转移瘤和肾上腺良性病变.

Diagnostic value of PET-CT in adrenal metastasis

Objective To investigate the value of 18F-FDG PET-CT in the diagnosis of adrenal metastasis.Methods 88 patients （107 adrenal lesions） with adrenal metastasis and benign tumor underwent 18F-FDG PET-CT,all adrenal lesions＇ short diameter,CT value and 18F-FDG maximum standardized uptake values （SUVmax） were measured.The t test,chi-square test and Pearson correlation test were used for data analysis.Meanwhile,receiver operating characteristic （ROC） curve was used to determine the ability of CT value and SUV~x to differentiate the adrenal metastasis and benign tumor.Results There were 73 adrenal metastases and 34 adrenal benign tumors of 107 adrenal lesions.The short diameter of adrenal metastasis was （2.17±1.14） cm,benign tumor was （1.76±1.00） cm,there was no statistical significant difference between the two groups （t =1.817,P =0.072）.The CT value of adrenal metastasis and benign tumor were （29.65±10.29） Hu and （14.83±14.42） Hu （t =5.389,P =0.000）,respectively.The SUVmax of adrenal metastasis was 9.28±5.33,while benign tumor was 2.81±1.14,statistical significant difference was found between the two groups （t =9.890,P =0.000）.For adrenal metastasis,a significant positive correlation was found between short diameter and SUV~ （r =0.620,P =0.000）,and it was also found between CT value and SUVmax （r =0.561,P =0.000）.Among all patients with adrenal metastasis,32 （58.2 ％） patients＇ lesions were found in the left adrenal gland,and 5 （9.1％） in the right side （x2 =29.689,P =0.000）.ROC curve analysis showed that using lesion＇ s SUVmax ＞ 4.1 and CT value ＞ 20 Hu as diagnostic criteria,the sensitivity,specificity,accuracy,PPV and NPV were 91.3 ％ （63/69）,94.7 ％ （36/38）,92.5 ％ （99/107）,96.9 ％ （63/65） and 85.7 ％ （36/42）,respectively.Conclusion 18F-FDG PET-CT has high sensitivity,specificity and accuracy in diagnosis of adrenal metastasis,and the adrenal lesion＇ s SUVmax ＞ 4.1 and CT value ＞ 20 Hu is a better diagnosti