CT增强静脉期直方图分析在甲状腺癌诊断和分型中的应用价值

Application value of histogram analysis based on enhanced CT venous phase images in the diagnosis andclassification of thyroid cancer

目的:探讨基于增强CT静脉期的直方图参数在诊断甲状腺癌(TC)及预测其病理分型中的应用价值。方法:将2017年4月-2021年4月在我院经手术或穿刺活检病理证实的103例甲状腺结节患者作为研究对象,包括良性结节82个、恶性结节37个(分化型24例,非分化型13例)。所有患者术前行颈部和上胸部CT平扫和双期(动脉期和静脉期)增强扫描。在静脉期图像上选取病灶最大层面沿病灶边缘勾画ROI后,软件自动生成灰度直方图,并获得均值、标准差、偏度、峰度及第1、10、50、90和99百分位数(Pk)等参数值。比较良性TN组与恶性TN组、分化型与非分化型组之间各项直方图参数值的差异,并采用ROC曲线分析各参数的诊断效能。结果:恶性结节组的均值、P50和P90高于良性结节组,方差低于良性结节组,差异均有统计学意义(P<0.05)。分化型组的均值、方差和P50低于非分化型组,差异均有统计学意义(P<0.05)。均值、方差、P50和P90鉴别良、恶性TN的AUC分别为0.871、0.744、0.827和0.747(P均<0.05);均值、方差和P50鉴别分化型与非分化型的AUC分别为0.609、0.763和0.696(P均<0.05)。结论:基于增强CT静脉期的直方图参数对良、恶性甲状腺结节的鉴别诊断效能较高,而且可为术前评估甲状腺癌的病理分型提供参考依据,有助于甲状腺癌的早期诊断和合理治疗。

Objective:To explore the application value of histogram parameters based on contrast-enhanced CT images at venous phase in the diagnosis of thyroid cancer(TC)and prediction of its pathological types.Methods:A total of 103 patients with thyroid nodules(TN)pathologically confirmed by surgery or puncture biopsy in our hospital from April 2017 to April 2021 were recruited as the study subjects.There were 82 benign nodules and 37 malignant nodules(including 24 of differen-tiated type and 13 of non-differentiated type).All patients underwent plain and dual-phase(arterial phase and venous phase)enhanced CT scan of the neck and upper chest.ROI was delineated along the edge of each lesion on the layer with the largest diameter on the venous phase images.Then,the gray histogram was automatically generated by the software and the histogram parameters including mean,standard deviation,skewness,kurtosis and the 1st,10th,50th,90th,and 99th percentiles(Pk)were obtained.The values of histogram parameters were compared between the benign TN group and malignant TN group and between differentiated group and non-differentiated group,and the diagnostic efficiency of the parameters was analyzed using ROC curve.Results:The mean,P50 and P90 of malignant TN group were higher than those of benign TN group,while the variance was lower than that of benign TN group(all P<0.05).The mean,variance and P50 were lower in differentiated group than those in non-differentiated group(all P<0.05).The AUCs of mean,variance,P50 and P90 were 0.871,0.744,0.827 and 0.747 respectively for differentiation of benign and malignant TN(all P<0.05).The AUCs of mean value,variance and P50 for identification of differentiated type and non-differentiated type were 0.609,0.763 and 0.696,respectively(all P<0.05).Conclusion:Histogram parameters based on enhanced CT images at venous phase have high diagnostic efficiency in the differential diagnosis of benign and malignant TNs,and can also provide a reference for the pathological types of TC,so it is beneficial for the early diagnosis and reasonable treatment of TC.