3D-MR Ductography and Contrast-Enhanced MR Mammography in Patients with Suspicious Nipple Discharge; a Feasibility Study

We evaluated contrast-enhanced magnetic resonance (ce-MR) imaging and an indirect MR galactogram (MRG) sequence against conventional galactography (CG) in women with suspicious nipple discharge who underwent histologic diagnosis. This study was Institutional Review Board approved and HIPAA compliant. Women with suspicious nipple discharge recommended for CG were recruited for our study. Patients underwent both a ce-MR as well as MRG (MRG-1 and MRG-2, variations in isotropic spatial resolution) followed by CG within 60days. The ce-MR and MRG studies were interpreted together by a single radiologist separately from CG. Pathology was used as our gold standard and was obtained via image-guided core needle biopsy or surgery with papilloma, atypia, and malignancy considered positive. Of the 21 patients recruited for the study, 20 patients had known histology results for 26 lesions; 18 patients (90.0%) had successful CG, 20 (100.0%) ce-MRI, 20 (100.0%) MRG-1, and 19 (95.0%) MRG-2. Histology showed 5 cancers (4 women), 15 papillomas (2 with atypia) (11 women), and 6 additional benign lesions (6 women). Five patients (25.0%) had additional lesions detected by ce-MR that influenced surgical management. Sensitivity, specificity, positive (PPV), and negative predicted values (NPV) for CG, ce-MRI, MRG-1 were 65.0, 33.3, 76.5, and 22.2; 95.0, 66.7, 90.5, and 80.8; 55.0, 66.7, 84.6, and 30.8, respectively. ce-MR had the highest sensitivity, PPV, and NPV compared with CG or MRG. Our MRG protocols show promise, but were not as sensitive as ce-MRI for women with suspicious nipple discharge.