剪切波弹性成像中不同定量测量方法预测乳腺癌腋下淋巴结转移能力

Different quantitative methods for shear wave elastography in predicting axillary lymph node metastasis

目的:探讨剪切波弹性成像技术(shear wave elastography,SWE)定量测量乳腺癌的硬度参数与腋下淋巴结转移(axillary lymph node metastasis,ALNM)状态的相关性,并比较SWE不同定量测量方法预测乳腺癌ALNM的能力,以获得最佳的预测参数。方法:纳入经SWE定量测量并获得肿物及淋巴结病理证实的304例乳腺癌患者进行前瞻性研究。用超声探头分别利用Q-box及Q-box trace不规则描记方法获取肿物弹性的定量参数,将纵、横两个切面的平均硬度、最大硬度和标准差的平均值作为各自的硬度平均值(Emean)、弹性最大值(Ema x)和标准差(SD)。用单变量和多变量回归分析评估ALNM与不同定量测量方法的各个参数之间存在的关系。结果:在单变量分析中,肿物大小,肿物位置,ER,PR,HER-2和SWE不同定量测量方法的各个参数值与淋巴结转移有显著的关联。在多因素分析中,肿物大小(P<0.001),HER-2(P=0.002),Q-box trace方法的SD(P=0.001)及Q-box的Mmean(P=0.028)对预测淋巴结状态具有独立意义。结论:剪切波弹性成像定量测量乳腺癌的硬度参数可作为预测ALNM的独立因素,为术前淋巴结状态的评估、手术方式的选择以及患者预后提供重要的信息。

Objective： To discuss the correlation between quantitative shear wave elastography （SWE） and axillary lymph node metastasis and compare different quantitative methods of shear wave elastography to obtain the better quantitative parameters. Methods： Data were prospectively analyzed from 304 consecutive patients with invasive breast cancer who had undergone SWE examination and treated by primary surgery. Four elastography images—in each of two orthogonal planes—were taken of each lesion using the Aixplorer ultrasound system. Quantitative measurements were produced and analysed by Q-box trace and Q-box. Take the average number of two orthogonal planes as Emean, Emax and SD. Associations between lymph node involvement and mean lesion stiffness, invasive cancer size, tumour location, histologic grade, tumour type, ER expression, PR expression, and HER-2 status were assessed using univariate and multivariate logistic regression. Results： At univariate analysis, invasive cancer size, tumour location, ER, PR, HER-2 and stiffness value of different quantitative methods were significantly associated with nodal involvement. At multivariate analysis, invasive size （P〈0.001）, HER-2 （P=0.002）, SD （P=0.001） of Q-box trace and Mmean （P=0.028） of Q-box maintained independent significance. Conclusion： Stiffness parameters of SWE are independent predictors of lymph node metastasis and thus can confer prognostic information additional to that provided by preoperative tumour and lymph node assessment and staging.