BACKGROUND: Methylene blue identification of lesions during microdochectomy is often inaccurate, resulting in large dissection and tissue damage. A wire placed via ductoscopy preoperatively into the pathologic duct may aid identification and reduce the amount of dissection required. METHODS: A total of 53 patients being evaluated for nipple discharge were randomized to receive ductoscopy with either methylene blue or wire marking of the lesion before microdochectomy. Patient clinical characteristics and surgical outcomes were evaluated. RESULTS: There were 28 patients who received methylene blue marking and 25 who received wire marking of the lesions. There were no differences between the demographic or clinical characteristics of the groups. Wire marking was associated with less surgical time, smaller incisions, and smaller surgical specimens, but the same diagnostic accuracy. CONCLUSIONS: Wire marking of lesions for microdochectomy is associated with less dissection and tissue damage than methylene blue, yet the same diagnostic accuracy. (C) 2011 Elsevier Inc. All rights reserved.