Feasibility of Narrow-Band Imaging, Intraductal Biopsy, and Laser Ablation During Mammary Ductoscopy: Protocol for an Interventional Study.

Introduction: Ductoscopy is a minimally invasive micro-endoscopic approach for direct visualization of intraductal lesions of the breast. Challenges of ductoscopy are low sensitivity for detecting malignancy, the lack of a proper intraductal biopsy device, and adequate treatment of intraductal lesions. This study will analyze three new approaches to enhance the effectiveness of interventional ductoscopy in patients with (premalignant) intraductal lesions: narrow-band imaging (NBI), new intraductal biopsy tools, and intraductal laser ablation. The main aims of the present study are to improve diagnostic accuracy and therapeutic efficacy of interventional ductoscopy in patients with pathological nipple discharge (PND) and to explore the feasibility of the new approaches in diagnosing and removing intraductal precursor lesions.

Methods and analysis: This prospective, single-center, diagnostic feasibility study will include two patient groups. Group A: women with PND with no radiological suspicion for malignancy. Group B: women undergoing mastectomy (preventive or therapeutic). The primary endpoints for both groups are the technical feasibility of NBI ductoscopy, intraductal biopsy, and laser ablation, and as secondary endpoint the number of diagnosed and successfully treated intraductal lesions.

Discussion: Enhanced ductoscopy with NBI, intraductal biopsy, and laser ablation could prevent unnecessary surgery in patients with PND.

Ethics and dissemination: This study was approved by the Medical Research Ethics Committee UMC Utrecht in The Netherlands (METC protocol number 21-688/H-D). The results of this study will be published in peer-reviewed journals and presented at national and international conferences.

Highlights: - Pathological nipple discharge (PND) is a common breast-related complaint in women.- Ductoscopy, a minimally invasive technique, is used in the treatment of PND.- This study will analyze three new approaches to enhance interventional ductoscopy of the breast: narrow-band imaging, new intraductal biopsy tools, and intraductal laser ablation in patients with (premalignant) intraductal lesions.