3.0T多模态MRI评估直肠癌T分期及新辅助治疗效果

3.0T multimodal MRI for evaluating T stage and therapeutic efficacy of neoadjuvant for rectal cancer

目的观察3.0T多模态MRI用于术前评估直肠癌T分期及新辅助治疗效果的价值。方法回顾性分析150例直肠癌患者多模态MRI资料,包括T1WI、T2WI/弥散加权成像(DWI)、动态对比增强MRI(DCE-MRI)、体素内不相干运动DWI(IVIM-DWI),观察各序列评估直肠癌T分期及新辅助治疗效果的价值。结果T1WI、T2WI/DWI、DCE-MRI、IVIM-DWI判断T1~T2期和T3~T4期直肠癌的敏感度、特异度及准确率差异均有统计学意义(P均<0.05);DCE-MRI和IVIM-DWI的诊断效能高于T1WI及T2WI/DWI(P均<0.05)。DCE-MRI与IVIM-DWI联合判断直肠癌T分期与病理学结果的一致性好(Kappa=0.943,P<0.05)。不同T分期直肠癌之间,容积转运常数(K^(trans))、真弥散系数(D)及表观弥散系数(ADC)差异均有统计学意义(P均<0.05)。80例接受新辅助治疗,疗效良好(n=32)与不良(n=48)患者K^(trans)、D及ADC差异均有统计学意义(P均<0.05)。K^(trans)、D及ADC评估直肠癌新辅助治疗效果的曲线下面积(AUC)分别为0.774、0.837及0.758,联合评估的AUC为0.929,高于各单一参数(P均<0.05)。结论3.0T DCE-MRI联合IVIM-DWI有助于术前评估直肠癌T分期及新辅助治疗效果。

Objective To observe the value of 3.0T multimodal MRI for preoperative evaluation of T stage and therapeutic efficacy of neoadjuvant for rectal cancer.Methods 3.0T multimodal MRI data,including T1WI,T2WI/diffusion weighted imaging(DWI),dynamic contrast enhanced MRI(DCE-MRI)and intravoxel incoherent motion DWI(IVIM-DWI)of 150 patients with rectal cancer were retrospectively analyzed,and the value of different sequences for evaluating T stage and therapeutic efficacy of neoadjuvant for rectal cancer were assessed.Results The sensitivity,specificity and accuracy of T1WI,T2WI/DWI,DCE-MRI and IVIM-DWI for evaluating T1—T2 and T3—T4 stage rectal cancer were all significantly different(all P<0.05).The diagnostic efficacy of DCE-MRI and IVIM-DWI were all higher than that of T1WI and T2WI/DWI(all P<0.05).Combination evaluation of DCE-MRI and IVIM-DWI for T stage of rectal cancer had good consistency with pathological results(Kappa=0.943,P<0.05).Significant differences of volume transfer constant(K^(trans)),true diffusion coefficient(D)and apparent diffusion coefficient(ADC)were found among different T stage rectal cancers(all P<0.05).Totally 80 patients received neoadjuvant therapy,and significant differences of K^(trans),D and ADC were noticed between patients with good(n=32)or poor efficacy(n=48)(all P<0.05).The area under the curve(AUC)of K^(trans),D and ADC for evaluating therapeutic efficacy of neoadjuvant for rectal cancer was 0.774,0.837 and 0.758,respectively,of the combination of above three was 0.929,higher than that of single indexes(all P<0.05).Conclusion Combination of 3.0T DCE-MRI and IVIM-DWI was helpful for preoperative evaluating T stage and therapeutic efficacy of neoadjuvant for rectal cancer.