DWI及DCE-MRI对乳腺纯导管原位癌、导管原位癌伴微浸润及浸润导管癌的鉴别诊断价值

The differential value of DWI and DCE-MRI in the diagnosis of pure ductal carcinoma in situ,micro-invasive ductal carcinoma in situ and invasive ductal carcinoma of breast

目的:探讨扩散加权成像(DWI)及动态增强磁共振成像(DCE-MRI)特征对乳腺导管原位癌(DCIS)、导管原位癌伴微浸润(DCIS-Mi)和浸润性导管癌(IDC)的鉴别诊断价值。方法:39例DCIS、43例DCIS-Mi和42例IDC患者,术前均行乳腺DCE-MRI和DWI检查。比较3组DWI和MRI-DCE特点。结果:纯DCIS、DCIS-Mi及IDC的最小ADC值(ADCMin)的中位数分别为1.35(1.33,1.36)、1.25(1.23,1.26)和1.08(1.06,1.12)×10-3mm^2/s,呈降低趋势且组间差异有统计学意义(P<0.05);最大与最小ADC值的差值(ADCDR)的中位数分别为0.13(0.11,0.14)、0.21(0.19,0.24)和0.34(0.31,0.37)×10-3mm^2/s,呈增高趋势且组间差异有统计学意义(P<0.05)。ADCMin值取1.285×10-3mm^2/s是鉴别纯DCIS和DCIS-Mi最佳阈值,取1.175×10-3mm^2/s是鉴别DCIS-Mi和IDC最佳阈值;ADCDR值取0.165×10-3mm^2/s鉴别纯DCIS和DCIS-Mi最佳阈值,取值0.265×10-3mm^2/s是鉴别纯DCIS-Mi和IDC最佳阈值。DCIS-Mi主要表现为非肿块强化,倾向于节段分布,内部强化特点为不均匀或簇环状强化,少数肿块样DCIS-Mi常边缘呈毛刺状或不规则,内部强化特点为不均匀或边缘强化;非肿块样纯DCIS趋向于线样分布,内部强化特点一般较均匀,肿块样DCIS往往边缘清晰,内部强化特点均匀或不均匀;IDC多表现为肿块样强化,其边缘和内部强化特点常表现多种形成。结论:DCE-MRI联合DWI有助于鉴别乳腺纯DCIS、DCIS-Mi和IDC,尤其ADCMin、ADCDR、簇环状强化和边缘强化强化对诊断DCIS-Mi有一定帮助。

Objective:To evaluate the value of diffusion-weighted imaging(DWI)and dynamic enhanced magnetic resonance imaging(DCE-MRI)in the differential diagnosis of ductal carcinoma in situ(DCIS),ductal carcinoma in situ with microinvasion(DCIS-Mi)and invasive ductal carcinoma(IDC)of breast.Methods:39 cases of DCIS,43 cases of DCIS-Mi,and 42 cases of IDC were collected.Breast DCE-MRI and diffusion weighted imaging(DWI)were performed preoperatively.The characteristics of ADCmin,ADCDR and DCE-MRI in the three groups were compared,and the diagnostic thresholds of ADCmin and ADCDR in the three groups were determined.Results:The quartiles of ADCmin of DCISs,DCISs-Mis and IDCs were 1.35(1.33,1.36),1.25(1.23,1.26)and 1.08(1.06,1.12)×10-3mm^2/s,showing a decreasing trend with statistical difference(P<0.05);the quartiles of ADCDR were 0.13(0.11,0.14),0.21(0.19,0.24),and 0.34(0.31,0.37)×10-3mm^2/s,showing an increasing trend with statistical difference(P<0.05).The ADCmin value of 1.285×10-3mm^2/s was taken as the best threshold to identify DCIS and DCIS-Mi,and 1.175×10-3mm^2/s as the best threshold to identify DCIS-Mi and IDC.The ADCDR value of 0.165×10-3mm^2/s was taken as the best threshold to identify DCIS and DCIS-Mi,and 0.265×10-3mm^2/s as the best threshold to identify DCIS-Mi and IDC.The DCIS-Mis were mainly manifested as non-mass enhancement,which tended to be segmental distribution,theirs internal enhancement was characterized by heterogeneous or clustered ring-like enhancement.A few mass-like DCIS-Mis usually showed spiculated or irregular margins,and their internal enhancement was characterized by heterogeneous or marginal enhancement.Non-mass-like DCISs tended to be linear distribution with a characteristic of internal homogeneous enhancement.Mass-like DCISs tended to have smooth margin,and their internal enhancement was characterized as homogeneous or heterogeneous enhancement.IDCs mostly presented as a mass-like enhanced lesion,their margin and internal enhancement characteristics varied.Conclusion:DCE-MRI combined with ADC value can help to distinguish breast DCIS,DCIS-Mi and IDC.Especially the parameters,such as ADCmin and ADCDR,and enhancement features,such as clustered ring-like and marginal are of more value for a diagnosis of DCIS-Mi.