Significance of nipple enhancement of Paget's disease in contrast enhanced breast MRI

Purpose: To evaluate significance of nipple enhancement of Paget's disease in contrast enhanced (CE) breast MRI. Methods: Ten patients of biopsy proven Paget's disease were included in this study. Preoperative mammogram and ultrasonogram (US) were obtained in all 10 patients, and 8 patients underwent CE breast MRI prior to surgery. Mammographic and US findings were reviewed retrospectively. On MRI, morphology (flattening or asymmetry or thickening) and enhancement of pathologically involved nipple were analyzed comparing with the opposite side, and also reviewed the abnormal enhancing lesion in the breast parenchyma. Results: Morphologic changes of the nipple were detected in 2 out of 10 patients by mammogram and 6 out of 10 patients by US. On MRI, morphologic change was also revealed in 7 patients and abnormal enhancement of involved nipple was observed in all 8 patients. Associated parenchymal enhancing lesions were proved to be DCIS (7 out of 10) and invasive ductal carcinoma (2 out of 10). Remaining one patient had no underlying breast parenchymal malignancy. Conclusion: CE breast MRI allows for the correct detection of nipple involvement of Paget's disease even when clinical information or mammographic/US findings are not provided.