Mammary ductoscopy for evaluation of nipple discharge

Background: Most breast cancers originate in the ductal epithelium with normal cells progressing to atypia and finally to carcinoma. Ductoscopy enables one to visualize and sample the ductal epithelium and therefore identify early changes cytologically. This report describes our experience with mammary ductoscopy as a tool for evaluation of nipple discharge at Beth Israel Medical Center. Methods: A prospective review of all patients who have undergone ductoscopy for evaluation of persistent nipple discharge was performed. The Acueity ductoscopy system with .9-mm scope and a video monitor with x60 magnification were used. Brush biopsy samples and lavage fluid were obtained from some patients and were sent for cytologic analysis. A subset of patients underwent ductoscopically guided duct excision. Results: Ninety-three patients underwent ductoscopic evaluation of 110 ducts. Of these, 67 patients had abnormal findings and therefore underwent ductoscopically guided duct excision. The remaining 26 patients (28%) had normal ductoscopic examinations. The depth at which intraductal abnormalities were visualized was from 3 to 8 cm with an average of 4.4 cm for cancer cases and from 1 to 10 cm with an average of 4.5 cm for papillomas. Forty-two patients were diagnosed with papilloma/papillomatosis, six patients were diagnosed with atypical papilloma/atypical ductal hyperplasia/atypical lobular hyperplasia, and six patients were diagnosed with cancer. Of the six patients diagnosed with cancer, 67% had normal breast imaging, and other than nipple discharge, 67% had normal breast examinations. Conclusion: Mammary ductoscopy is a useful tool in the evaluation of patients with nipple discharge. Although the most common cause of nipple discharge is an intraductal papilloma, nipple discharge can be the presenting symptom for cancer. Our experience revealed a papilloma rate of 45% (42 of 93), cancer rate of 6.5% (6 of 93), and an atypia rate of 6.5% (6 of 93) among the patients with nipple discharge. Mammary ductoscopy allows for accurate visualization, analysis, and excision of intraductal abnormalities. Many deeper intraductal abnormalities could be missed by blind surgical excision.