摘要目的 探讨胸腺瘤瘤周结节CT定量特征预测其侵袭性的价值.方法 回顾性分析2013年3月至2018年10月北京大学第三医院具有完整临床、影像及手术病理资料的110例胸腺瘤,其中男65例、女45例,中位年龄45岁.根据胸腺瘤2004年世界卫生组织标准,按侵袭性程度分为高危组(男23例、女15例,中位年龄52岁)与低危组(男42例、女30例,中位年龄42岁).分析胸腺瘤瘤周结节的长径、双期增强CT值、ΔCT值及与主瘤体距离.有预测价值的CT定量参数及阈值通过Mann-Whitney U检验和受试者特征曲线(ROC)分析和确定.结果 110例胸腺瘤中,28例增强CT表现有瘤周结节,B1型12例、B2型7例、B3型6例、C型3例,A型及AB型中未发现瘤周结节.瘤周结节出现在高危组16例、低危组12例.高危组瘤周结节长径、双期增强CT值、ΔCT值及与主瘤体距离分别为(9.8±3.7)mm,(48±27)、(51±21)、(17±10) HU及(6.3±6.5)mm;低危组瘤周结节长径、双期增强CT值、ΔCT值及与主瘤体距离分别为(5.5±1.6)mm,(55±18)、(52±19)、(14±10) HU及(3.9±2.2) mm.低危与高危组比较,瘤周结节的双期强化CT值、ΔCT值及与主瘤距离差异均无统计学意义(均P＞0.05),而高危瘤周结节的长径显著＞低危组(P＜0.05).ROC曲线分析,以瘤周结节长径为6.9 mm为阈值,预测胸腺瘤高危,相应的曲线下面积、敏感度和特异度分别为0.862、75.0％和75.0％.结论 胸腺瘤瘤周结节CT定量特征指标中,结节长径有助于预测其侵袭性.

abstractsObjective To explore the value of CT quantitative features of peritumoral nodules in predicting invasiveness of thymoma.Methods A retrospective study of 110 patients (65 males and 45 females,with a median age of 45 years) of thymoma with complete clinical,imaging and pathological data in Peking University Third Hospital from March 2013 to October 2018.Patients were divided into high risk (23 males and 15 females,with a median age of 52 years) and low risk groups (42 males and 30 females,with a median age of 42 years) according to the 2004 WHO criteria of thymoma.The major diameter,dual phase contrast CT values,ΔCT values and distance to main tumor of peritumoral nodule were analyzed.The predictive value of CT quantitative parameters were examined with Mann-Whitney U test and ROC curves.Results Among 110 cases of thymoma,28 cases had peritumoral nodules.The pathological classification of thymoma were type B1 (12 cases),type B2 (7 cases),type B3 (6 cases) and type C(3 cases).No peritumoral nodules were found in type A and AB.Sixteen patients were categorized into the high risk group whereas the other 12 patients were considered low risk.For high risk group,the major diameter,dual phase contrast CT values,ΔCT values and distance to main tumor of peritumoral nodule were (9.8±3.7) mm,(48±27)HU,(51± 21)HU,(17± 10)HU and (6.3±6.5)mm,respectively;and for low risk group,the major diameter,dual phase contrast CT values,ΔCT values and the distance to main tumor of peritumoral nodules were (5.5± 1.6)mm,(55± 18)HU,(52± 19)HU,(14± 10)HU and (3.9±2.2)mm,respectively.Compared with the low risk group,the major diameter was significantly higher in high risk group (P＜0.05).In contrast,dual phase contrast CT values,ΔCT values and the distance to main tumor only changed slightly (all P＞0.05).The ROC curve analysis indicated that,the cutoff of the major diameter of peritumoral nodule predicting tumor's high risk was 6.9 mm,and the corresponding AUC,sensitivity,and specificity was 0.862,75.0％ and 75.0％,respectively.Conclusion The major diameter of peritumoral nodule can potentially predict the invasiveness to thymoma.