多模态MR成像在评估乳腺癌新辅助化疗疗效中的价值

The Value of Multimodal MRI in Evaluating the Efficacy of Neoadjuvant Chemotherapy for Breast Cancer

目的探讨3.0T多模态MR成像对乳腺癌新辅助化疗疗效评估的价值。方法连续性收集行全程新辅助化疗(NAC)并最终行手术治疗的51例非特殊型浸润性导管癌(NS-IDC)患者,分别于NAC前、化疗结束后1~2周内行多模态MR检查,测量并计算各参数值。根据NAC前穿刺活检结果,分为分化较好组和分化较差组。按NAC后病理评估结果,分为组织学显著反应(MHR)组和组织学非显著反应(NMHR)组。探讨NAC前后两组癌灶最大径(D)、表观扩散系数(ADC)、平均扩散系数(MD)、平均扩散峰度(MK)值及其变化率的差异,分析各参数值与NAC疗效的相关性,使用受试者工作特征(ROC)曲线确定多模态MR成像参数对化疗疗效评估的诊断效能,并获得诊断临界点。结果显著反应组19例,非显著反应组32例。NAC后,两组病灶的D、ADC、MD、MK值及其变化率均有显著差异,且诊断效能较高。MR与病理测量最大径值呈高度正相关(r=0.912,P<0.01)。△MD%、△D%、△ADC%、△MK%预测疗效的ROC下面积分别为0.90、0.89、0.87、0.67,最佳临界预测值分别为21.15%、69.19%、55.30%、30.15%,评估的敏感性分别系94.7%、73.7%、63.2%、57.9%,特异性系78.1%、96.9%、96.9%、71.9%。结论应用多模态MR成像技术可从多方位探测肿瘤组织化疗前后动态变化特征,△MD%、△D%对乳腺癌NAC疗效评价具有较高的诊断价值。

Objective To investigate the value of 3.0T multimodality magnetic resonance imaging in evaluating the efficacy of neoadjuvant chemotherapy(NAC)for breast cancer.Methods A continuous collection of 51 patients with non-specific invasive ductal carcinoma(NS-IDC)who underwent full course of neoadjuvant chemotherapy(NAC)and eventually surgery were collected.All patients underwent multimodal MR examination before NAC and within 1~2 weeks after chemotherapy,and the values of each parameter were measured and calculated.According to histologic grading before NAC,the patients were classified into well-differentiated and poor-differentiated group.The patients were classified into major histological response(MHR)and non-major histological response(NMHR)according to the results of pathological evaluation.To investigate the difference of D,ADC,MD,MK and change rate between the two groups,analyze the correlation between each parameter value and NAC efficacy.The receiver-operating characteristic curve(ROC)was used to determine the efficacy of multimodality MR imaging parameters to evaluate the efficacy of chemotherapy and to obtain the diagnostic cut-off point.Results There were 19 cases of MHR and 32 cases of NMHR.After NAC,The maximum diameter of tumors(D),ADC,MD,MK values,and their preoperative rate of change were significantly different between the two groups,and the diagnostic efficiency was higher.The maximum diameter measured with MRI measurement were positively correlated to that of pathological results(r=0.912,P<0.01).ROC analysis showed that the area under ROC curve of△MD%,△D%,△ADC%,△MK%in predicting treatment effect were 0.90,0.89,0.87 and 0.67 respectively.Using 21.15%of△MD%,69.19%of△D%,55.30%of△ADC%,30.15%of△MK%after NAC as the cut off value to predict MHR,the sensitivity were 94.7%,73.7%,63.2%,57.9%respectively and specificity were 78.1%,96.9%,96.9%,71.9%respectively.Conclusion The application of multimodality MR imaging technology can detect the dynamic changes of tumor tissues before and after chemotherapy from multiple directions,and△MD%and△D%have high diagnostic value for the evaluation of the efficacy of NAC in breast cancer.