RESUMO
To explore the values of minimal apparent diffusion coefficient(ADC),difference between ratios of apparent diffusion coefficients(ADC),and dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)in the treatment of breast ductal carcinoma in situ with microinvasion(DCIS-Mi). Totally 27 patients with DCIS-Mi and 31 patients with breast ductal carcinoma in situ(DCIS)were collected in our hospital from October,2016 to June,2018.Philips Ingenia 3.0T superconducting magnetic resonance scanner and dedicated phase-controlled array surface coil were used for breast examinations.ADC and maximum apparent diffusion coefficient(ADC)were selected from multiple regions of interest(ROI)in the apparent diffusion coefficients(ADC)figure,and ADC was calculated.In addition,DCE-MRI characteristics were analyzed. The ADC of DCIS-Mi was significantly lower than that of DCIS[(1.15±0.03)×10 mm /s .(1.34±0.04)×10 mm /s,=-7.192,=0.002],the ADC was significantly higher than that of DCIS[(0.32±0.03)×10 mm /s .(0.18±0.08)×10 mm /s,=-10.228,<0.001],and the early enhancement rate of DCIS-Mi was higher than that of DCIS[159.71(157.82,162.49)% .147.29(143.59,160.22)%,=-3.578,=0.007].The background parenchymal enhancement of DCIS-Mi was moderate,severe,and non-lump-like,mainly segmental,and the internal enhancement was heterogeneous or clustered circular.Multivariate Logistic regression analysis showed that non-internal characteristics of the mass,the edge of the mass,internal enhancement characteristics of the mass,time-intensity curve,early enhancement rate,ADC and ADC were the optimal variables for the diagnosis of DCIS-Mi,and the optimal variables were shown by receiver operating characteristic(ROC)curve analysis:the area under curve,sensitivity and specificity of ADC,ADC,non-tumor internal enhancement,and tumor internal enhancement were higher,with the critical values being 1.12×10 mm /s,0.31×10 mm /s,1.50,and 1.50,respectively. DCE-MRI combined with ADC value(especially ADC,ADC,non-mass internal enhancement,and mass internal enhancement)is helpful in differentiating breast DCIS-Mi and DCIS.