Study Of MR Imaging In Dignosing Breast Cancer

Part I The diagnosis of breast cancer in the three-dimentional dynamic contrast anddigital subtraction MR imagingObjective To analysis the morphologic features and enhancement kinetics of breast lesion with three-dimentional dynamic contrast and digital subtraction MRI and to evaluate the application of MRI in diagnosing breast cancer.Methods 51 patients were enrolled in this study,including 27 malignant lesions and 36 benign lesions verified by histopathology. the morphologic features and enhancement kinetics of breast lesion in MRI were observed and compared. the morphologic manifestation,early-phase enhanement rates ,peak enhanement rates, peak time and time-signal intensity curve were evaluation in diagnosing breast diseases.Results The benign lesions are mainly characterized by regular mass,clear boundary,internal septation,homogeneous enhancement, early-phase enhanement rates less 90%,peak time less 3 minutes,type I time-signal intensity curve,the malignant lesions by irregular shape,speculated margin,rim enhancement,imhomogeneous enhancement, early-phase enhanement rates more than 90%, peak time beyond 3 minutes and type II,III time-signal intensity curve. The early-phase enhanement rates ,peak time and distribution of time-signal intensity curve proved significantly diffrernt (p<0.05). With the morphologic feature of malignant lesions,the following diagnostic indices emerge:sensitivity81.5%,specificity88.9 % and diagnostic accuracy 85.7%.With early-phase enhanement rates more than 90% , peak time beyond 3 minutes and type II,III time-signal intensity curve for malignant lesions, the following diagnostic indices emerge:sensitivity 88%,77.8%,88.9%,specificity62%,87.9%,72.4% and diagnostic accuracy 68%,83.3%,80%,respectively.Conclusion The benign lesions are characterized by regular mass,clear boundary,internal septation,homogeneous enhancement, early-phase enhanement rates less90%, peak time less 3 minutes ,type I curve,the malignant lesions by irregular shape,speculated margin,rim enhancement,imhomogeneous enhancement, early-phase enhanement rates more than 90% , peak time beyond 3 minutes and type II,III curve. The early-phase enhanement rates ,peak time and distribution of time-signal intensity curve are very usefull for in diagnosing breast cancer.But there is an overlap in some patients.