纹理分析对经动脉化学栓塞治疗术后肝癌复发的评价

Value of texture analysis in evaluating liver cancer recurrence after transarterial ehemoembolization

目的探讨CT增强纹理分析预测肝癌经动脉化学栓塞治疗（TACE）术后患者早期复发的可行性。方法回顾性分析TACE术前行上腹部CT增强检查、经穿刺病理、数字减影血管造影证实的肝癌患者47例，以半年内有无局灶性复发为界，分为早期复发（ER）与非早期复发（NER）两组，应用纹理分析在肝癌术前CT轴位增强图像上逐层勾画肿瘤边界，统计得到两组患者整个瘤体异质性的相关参数：熵值、平均值、不均匀度、偏度及峰度等。采用独立样本f检验对两组间纹理分析参数进行比较，对熵值、均数及不均匀度三组参数进行受试者工作特征曲线分析，分别计算曲线下面积、最佳截断点、敏感度及特异度，评价其对TACE术后早期局灶性复发的预测效能。结果ER组20例，NER组27例。ER组肿瘤最大径线明显大于NER组，最大长径分别为（88．2±36．3）mm、（41．4±21．4）mm，短径分别为（66．9±30．2）mm、（29．3±19．8）mm，差异有统计学意义（f值分别为4．89、4．62，P〈0．001）。ER组中熵值及不均匀度明显高于NER组，均值在ER组中偏低；而两组间偏度和峰度差异无统计学意义。熵值、不均匀度及均数对TACE术后早期复发具有较高的预测效能，熵值最佳截断点为4．135。结论通过术前肝癌CT增强图像的容积纹理分析，对TACE术后早期复发具有较高的预测价值。

Objective To investigate the feasibility of contrast-enhanced computer tomography （CT） texture analysis in predicting early recurrence after transarterial chemoembolization （TACE） in patients with liver cancer. Methods A retrospective analysis was performed for 47 patients with liver cancer confirmed by liver biopsy and digital subtraction angiography who underwent upper abdominal contrast-enhanced CT scan before TACE, and according to the presence or absence of focal recurrence within half a year, these patients were divided into early recurrence （ER） group and non-early recurrence （NER） group. The texture analysis was used to delineate tumor boundary layer by layer on the axial contrast-enhanced CT image before liver cancer surgery, and related parameters of ttmaor heterogeneity, including entropy, mean, non-uniformity, skewness, and kurtosis, were obtained. The independent samples t-test was used for comparison of texture parameters between the two groups. The receiver operating characteristic （ROC） curve was used for the analysis of entropy, mean,and non-uniformity, and the area under the ROC curve （ROC）, optical cut-off value, sensitivity, and specificity were calculated to evaluate the efficiency of texture analysis in predicting early focal recurrence after TACE. Results There were 20 patients in the ER group and 27 in the NER group. The ER group had a maximum major axis length of 88.2±36.3 mm and a maximum minor axis length of 41.4±21.4 mm, and the NER group had a maximum major axis length of 66.9±30.2 mm and a maximum minor axis length of 29.3±19.8 mm; the ER group had significantly higher maximum major and minor axis lengths than the NER group （t = 4.89 and 4.62, P 〈 0.001）. The ER group had significantly higher entropy and non-uniformity values than the NER group, and there were no significant differences in skewness and kurtosis between the two groups. Entropy, non-uniformity, and mean had high efficiency in predicting early recurrence after TACE, and the optimal cut-offvalue of entropy was 4.135. Conclusion Volumetric texture analysis of contrast-enhanced CT images before liver cancer surgery has a high value in predicting early recurrence after TACE.