Abstract:Objective: To evaluate the usefulness of MR T2 mapping in differentiating breast carcinoma from benign lesions. Materials and Methods: MR T2 mapping data was obtained from 13 lesions of breast carcinoma and 13 lesions of breast benign lesions. The mean value(μ) and standard deviation(σ) of T2 values in the lesions were measured. The coefficient of variance(CV) of the lesion was defined as CV=σ/μ. The μ values and CVs were compared in the two groups. The receiver operating characteristic(ROC) curve was used to evaluate the diagnostic value of μ values and CVs of T2 values for breast carcinoma, and then determine the cut-off point. Result: There were no obvious differences between the mean value of breast carcinoma and breast benign lesions(t=1.164, P=0.256). There were statistically difference between CVs of breast carcinoma and breast benign lesions(t=6.203, P=0.000). When ROC analysis of the CVs of T2 values of breast carcinoma as a diagnostic indicator, area under the curve(AUC) is 0.964(AUC>0.9, high diagnostic value), as the cut-off point was 0.145, the diagnosis of breast cancer with this standard, sensitivity is 92.3%(12/13), specificity is 100%(13/13), and the accuracy is 0.962(25/26). When ROC analysis of μ values of T2 of breast carcinoma as a diagnostic indicator, AUC is 0.627(AUC is between 0.5 and 0.7, low diagnostic value). Conclusion: In MR T2 mapping imaging, CV of T2 values of breast malignant lesions is higher than that of benign lesions. The CV of T2 values of breast lesions is more useful than the mean value in distinguishing breast carcinoma from breast benign lesions.