摘要
目的分析常规弥散加权成像(DWI)表观弥散系数(ADC)在评价局部进展期直肠癌患者新辅助放化疗疗效中的价值。方法收集2014年1月—2015年9月复旦大学附属肿瘤医院收治的符合标准的局部进展期直肠癌患者56例(T3、T4期和/或淋巴结阳性),新辅助放化疗前后各行一次3.0T MRI检查,DWI序列分别取4个b值(0、700、1 400和2 100 s/mm2)。手工画取整个肿瘤的感兴趣区(ROI),避开直肠病灶周围伪影及肉眼可见的囊变坏死区,以T2加权图像为参照在ADC图上画ROI,从而获得治疗前ADC(ADCpre)、治疗后ADC(ADC_(post))及ADC比值(ADC_(ratio))。分别采用病理完全缓解(p CR)、肿瘤退缩分级(TRG)及肿瘤降期(T-downstaging)作为评判标准。通过比较治疗前和术后病理分期来确定是否降期,术前分期为T3~4期,术后T分期降至T2期及以下的患者为T降期组;TRG 0~1级患者为TRG缓解组,TRG 2~3级患者为TRG非缓解组;即TRG 0级且无阳性淋巴结存在患者为p CR组。结果 p CR组ADC_(post)、ADC_(ratio)均高于非p CR组(P<0.05);TRG缓解组ADC_(post)、ADC_(ratio)均高于TRG非缓解组(P<0.05);T降期组ADC_(post)、ADC_(ratio)均高于T非降期组(P<0.05)。ADCpre评价p CR最佳截断值≤0.82×10-3 mm2/s时,ROC曲线下面积为0.583[95%CI(0.44,0.71)],灵敏度为57.1%(8/14),特异度为69.0%(29/42),正确率为66.1%(37/56)。ADC_(post)评价p CR最佳截断值>1.17×10-3 mm2/s时,ROC曲线下面积为0.823[95%CI(0.70,0.91)],灵敏度为92.9%(13/14),特异度为66.7%(28/42),正确率为73.2%(41/56)。ADC_(ratio)评价p CR最佳截断值>0.43时,ROC曲线下面积为0.793[95%CI(0.66,0.89)],灵敏度为78.6%(11/14),特异度为73.8%(31/42),正确率为75.0%(42/56)。ADCpre评价TRG最佳截断值≤0.88×10^(-3) mm^2/s时,ROC曲线下面积为0.567[95%CI(0.43,0.70)],灵敏度为77.3%(17/22),特异度为50.0%(17/34),正确率为60.7%(34/56)。ADC_(post)评价TRG最佳截断值>0.20×10-3 mm2/s时,ROC曲线下面积为0.773[95%CI(0.64,0.87)],灵敏度为72.7%(16/22),特异度为79.4%(27/34),正确率为76.8%(43/56)。ADC_(ratio)评价TRG最佳截断值>0.37时,ROC曲线下面积为0.721[95%CI(0.59,0.83)],灵敏度为68.2%(15/22),特异度为70.6%(24/34),正确率为69.6%(39/56)。ADCpre评价T降期最佳截断值≤0.82×10-3 mm2/s时,ROC曲线下面积为0.545[95%CI(0.41,0.68)],灵敏度为46.2%(12/26),特异度为70.0%(21/30),正确率为58.9%(33/56)。ADC_(post)评价T降期最佳截断值>1.23×10-3 mm2/s时,ROC曲线下面积为0.747[95%CI(0.61,0.85)],灵敏度为57.7%(15/26),特异度为90.0%(27/30),正确率为75.0%(42/56)。ADC_(ratio)评价T降期最佳截断值>0.59时,ROC曲线下面积为0.682[95%CI(0.54,0.80)],灵敏度为46.2%(12/26),特异度为90.0%(27/30),正确率为69.6%(39/56)。结论 ADC_(post)及ADC_(ratio)在预测及评价局部进展期结直肠癌患者新辅助放化疗后的疗效中具有较高的诊断效能。
Objective To assess the value of apparent diffusion coefficient(ADC)calculated using conventional diffusion-weighted imaging(DWI)in evaluating the response to neoadjuvant chemoradiotherapy(CRT)in patients with locally advanced rectal cancer(LARC).Methods Between January 2014 and September 2015,56 consecutive patients diagnosed with LARC(T3,T4,and/or lymph node positive)were prospectively enrolled and underwent pre-and post-neoadjuvant CRT MRI using a 3.0 T MRI scanner in Fudan University Shanghai Cancer Center.DWI sequences were performed with b values of 0,700,1 400,and 2 100 s/mm2,respectively.Regions of interest(ROI)were manually drawn on each cross-sectional area of the primary lesions,simultaneously avoiding the encircle distortion artifacts and macroscopically visible necrotic or cystic portions in the axial ADC map deriving from T2-weighted images.Then,the value of ADCpre,ADCpost,and ADCratio were obtained.Pathological complete remission(pCR),tumor regression grade(TRG)and tumor downstaging(T-downstaging)were used as the evaluation criteria.Downstaging was determined by comparing the pretreatment and postoperative pathologic classifications.Patients with ypT0-2N0(the“yp”prefix indicates final staging after CRT[y]and postoperative pathologic examination[p])were defined as T-downstaging,those with TRG 0 or TRG 1 were classified as good responders,whereas the remaining patients with TRG 2-3 were classified as poor responders,and if no tumor cells were identified in the resected specimen and only fibrotic mass or acellular mucin pools were present,the type of response was considered as complete response(ypT0N0)and the patient was labeled as pCR.Results The ADCpost and ADCratio values in pCR patients were much higher than those in non-pCR patients(P<0.05),as well as in the evaluation criteria of TRG and T-downstaging(P<0.05).The optimal cutoff value for the identification of patients with pCR was≤0.82×10-3 mm2/s for ADCpre{during which its AUC was 0.583〔95%CI(0.44,0.71)〕,with 57.1%(8/14)sensitivity,69.0%(29/42)specificity,and 66.1%(37/56)accuracy,respectively},>1.17×10-3 mm2/s for ADCpost{during which its AUC was 0.823〔95%CI(0.70,0.91)〕with 92.9%(13/14)sensitivity,66.7%(28/42)specificity,and 73.2%(41/56)accuracy,respectively}and>0.43 for ADCratio{during which its AUC was 0.793〔95%CI(0.66,0.89)〕with 78.6%(11/14)sensitivity,73.8%(31/42)specificity,and 75.0%(42/56)accuracy,respectively}.In addition,the optimal cutoff value for the identification of patients with TRG0-1 was≤0.88×10-3 mm2/s for ADCpre{during which its AUC was 0.567〔95%CI(0.43,0.70)〕,with 77.3%(17/22)sensitivity,50.0%(17/34)specificity,and 60.7%(34/56)accuracy,respectively},>0.20×10-3 mm2/s for ADCpost{during which its AUC was 0.773〔95%CI(0.64,0.87)〕,with 72.7%(16/22)sensitivity,79.4%(27/34)specificity,and 76.8%(43/56)accuracy,respectively}and>0.37 for ADCratio{during which its AUC was 0.721〔95%CI(0.59,0.83)〕,with 68.2%(15/22)sensitivity,70.6%(24/34)specificity,and 69.6%(39/56)accuracy,respectively}.Finally,the optimal cutoff value for the identification of patients with T-downstaging was≤0.82×10-3 mm2/s for ADCpre{during which its AUC was 0.545〔95%CI(0.41,0.68)〕,with 46.2%(12/26)sensitivity,70.0%(21/30)specificity,and 58.9%(33/56)accuracy,respectively},>1.23×10-3 mm2/s for ADCpost{during which its AUC was 0.747〔95%CI(0.61,0.85)〕,with 57.7%(15/26)sensitivity,90.0%(27/30)specificity,and 75.0%(42/56)accuracy,respectively}and>0.59 for ADCratio{during which its AUC was 0.682〔95%CI(0.54,0.80)〕,with 46.2%(12/26)sensitivity,90.0%(27/30)specificity,and 69.6%(39/56)accuracy,respectively}.Conclusion The ADCpost and ADCratio have high-level capabilities for identifying the response to neoadjuvant CRT in LARC patients.
作者
胡飞翔
张换
汤伟
彭卫军
童彤
HU Fei-xiang;ZHANG Huan;TANG Wei;PENG Wei-jun;TONG Tong(Department of Radiology,Fudan University Shanghai Cancer Center,Shanghai 200032,China;Department of Oncology,Shanghai Medical College,Fudan University,Shanghai 200032,China)
出处
《中国全科医学》
CAS
北大核心
2018年第6期658-664,共7页
Chinese General Practice
基金
国家自然科学基金资助项目(81501437)
关键词
直肠肿瘤
弥散磁共振成像
病理完全缓解
Rectal neoplasms
Diffusion magnetic resonance imaging
Pathological complete response
