Could ductoscopy alleviate the need of microdochectomy in pathological nipple discharge?

Background Microdochectomy is the gold-standard for definitive diagnosis for pathological nipple discharge (PND); however, problem of over-treating exists since majority of PND are self-limiting and due to benign causes. Ductoscopy may assist diagnosis, and triage patients for intervention or expectant management. This study aimed to evaluate if ductoscopy could reduce unnecessary microdochectomy but not compromising the diagnosis of malignancy. Method A multicenter, retrospective study was conducted in consecutive patients of PND without a suspected malignancy on routine diagnostic evaluation. Ductoscopy was performed with attempts to remove intraductal lesions if they were found. Microdochectomy was carried out if there were positive intraductal lesions, but failed endoscopic extraction, or failed ductoscopy and persistent PND. Efficacy of ductoscopy was determined by cannulation success rate, number of avoided surgery and number of missed malignancy. Results In a 3-year period between 2016 and 2018, a total of 223 ductoscopy were performed and 94.2% had successful cannulation. Within such, 59.5% ( N = 125) had intraductal mass identified, and 82 microdochectomy were carried out. The final histology showed 15 malignancy, making the overall malignancy rate 6.7%. Ductoscopy successful and negative patients ( N = 85, 37.8%) were triaged for surveillance and the malignancy rate is 0% in a median follow-up of 2 years; hence, microdochectomy was avoided. Conclusion PND with non-suspicious conventional imaging and negative ductoscopy have rare malignancy rate which makes subsequent microdochectomy unnecessary. However, intraductal mass in ductoscopy is a predictor for malignancy so definitive histology diagnosis is mandatory.