Objective To investigate the value of multimodality MRI in diagnosis of breast lesions with ring enhancement (internal enhancement pattern) on dynamic contrast enhanced (DCE) MRI.Methods Data of 67 patients with breast lesions confirmed by surgical pathology who underwent DCE MRI and DWI examinations were analyzed retrospectively.Finally,67 patients with breast lesions manifested as ring enhancement on DCE MRI were included in the study.According to the pathological findings,all patients were divided into benign group and malignant group.The overall morphology,morphology of "enhanced ring",time-signal intensity curve (TIC) types on DCE MRI,the distribution location of limited diffusion on DWI between the two groups were compared.Also the differences in semi-quantitative parameters on DCE-MRI and multi-point ADC values of the "enhanced ring" between the two groups were compared.Using pathological results as the dependent variables,indexes with statistical differences as the independent variables,the Logistic regression model was established to construct the newly combined parameters and to evaluate the diagnostic efficacy of the stepwise combined parameter.Results There were significant differences of different wall shapes concerning "enhanced ring" (x2 =14.19,P=0.001),wall nodules (x2 =12.48,P=0.001) and distribution locations of limited diffusion on DWI (x2 =19.60,P=0.003) between the two groups.There were also significant differences of the semi-quantitative parameters including early enhancement ratio (EER;t=2.35,P=0.02),maximum enhancement time (Tmax;t=-4.66,P=0.007),ADC ringi (t=1.35,P=0.001) and ADC ring wall(t=-2.88,P=0.005)between the two groups.The maximum Youden index of a newly-constructed parameter combination(morphological indexes of "enhanced ring"+distribution locations of limited diffusion on DWI+Tmax+ADCring inner) was 0.83 for combined diagnosis.The area under ROC curve was 0.87 (95％CI [0.82,0.91]),and the diagnostic sensitivity and specificity was 91.96％ and 91.31％,respectively.Conclusion Multimo dality MR can provide high diagnostic efficacy for breast lesions with ring enhancement