局部进展期直肠癌纹理分析的可重复性研究

Reproducibility of texture analysis in locally advanced rectal cancer

目的:探讨局部进展期直肠癌新辅助放化疗前、疗中不同测量者之间纹理参数的一致性及可重复性。方法:回顾性分析57例局部进展期直肠癌患者新辅助放化疗疗前、疗中的MRI资料。所有的纹理参数后处理均在Omni-Kinetics软件上进行。由一位高年资医生在T2WI序列图像上选取肿瘤实性成份最大的层面用于测量,另外由两位医生分别在选取的层面手动勾画感兴趣区。软件自动生成18个二阶的灰阶共生矩阵(GLCM)纹理参数。取每次测量的平均值用于统计学分析,两位医生测量数据的一致性采用组内相关系数(ICC)表示。结果:全部18个GLCM纹理参数中,新辅助放化疗前、疗中两位医生间一致性较好的参数均为16个,ICC范围分别为0.842~0.996和0.818~0.996。SumAverage参数在新辅助放化疗前、疗中的一致性均最好,ICC值分别为0.996(95%CI:0.993~0.998)和0.996(95%CI:0.994~0.998);而Correlation参数的一致性均较差,ICC值分别为0.610(95%CI:0.338~0.770)和0.601(95%CI:0.322~0.765)。新辅助放化疗中两位医生间纹理参数测量的一致性较疗前无明显变化。结论:局部进展期直肠癌新辅助放化疗前、疗中,两位医生间二阶GLCM纹理参数测量的一致性及可重复性均较好。

Objective:To investigate the consistency and reproducibility of texture analysis between different radiologists before and during neoadjuvant chemoradiation treatment(nCRT)for locally advanced rectal cancer.Methods:The data of pre-and during early nCRT MR examinations of 57 patients with locally advanced rectal cancer were retrospectively studied.The Omni-Kinetics software was used to obtain Gray level co-occurrence matrix(GLCM)texture metrics.The section of largest tumor area depicted on the oblique axial T 2WI MR images was chosen for analysis by one senior radiologist.Regions of interest(ROIs)were drawn manually on the selected section of the largest tumor area by two radiologists,respectively.Then 18 pre-and early nCRT second-order GLCM texture metrics were obtained automatically by the software.Mean values were used for analysis.Interobserver agreement was characterized by using the intraclass correlation coefficient(ICC)for continuous variables.Results:The ICCs of 16 metrics within total 18 GLCM texture metrics were excellent both before and during nCRT,with the range of ICC of 0.842~0.996 and 0.818~0.996,respectively.The ICC of SumAverage parameter was the best,with ICC values of 0.996(95%CI 0.993~0.998)and 0.996(95%CI 0.994~0.998)pre-and during nCRT,respectively;while the Correlation parameter was relatively poor,with ICC values of 0.610(95%CI 0.338~0.770)and 0.601(95%CI 0.322~0.765)pre-and during nCRT,respectively.The variances of ICCs between the pre-and early nCRT were not significantly different.Conclusions:The consistency and reproducibility of second-order GLCM texture metrics between radiologists was good in locally advanced rectal cancer before and during nCRT.