Intraductal Neoplasias of the Breast (IDNB), as the main cause of pathological nipple discharge (PND), is characterized by histopathological heterogeneity, high risk of malignancy and the need for morphological verification. Cytological analysis is ineffective and should be coordinated with histopathology. Targeted biopsies are impossible for X-ray- and echo-negative IDNB, which occur with a frequency of up to 85 and 71%, respectively. Open biopsy in the form of ductectomy with localization of the secretory duct is not cost-effective, requires hospitalization, is traumatic and often leaves IDNB, especially peripherally located, outside the resection. For the diagnosis and treatment of PND, we use traditional and patented⁕ techniques in accordance with the following algorithm (figure). In our opinion, the advantages of this algorithm are primarily in the use of endoscopic ductoscopy, which provides a direct visual assessment of the IDNB and in many cases allows to avoid such expensive technologies as mammographic 3D tomosynthesis or MRI. The proposed algorithm ensures an optimal sequence of diagnostic and therapeutic manipulations, eliminates unnecessary duplicative approaches, justifies the need for surgery, and objectifies the choice of the surgical method. At the same time, less traumatic selective ductectomy is performed more often (91.0%), the volume of excised tissue decreases by an average of 21.6 cm3, and there is a guarantee of adequate resection of all IDNB diagnosed by ductography and/or endoscopy before surgery. In addition, the frequency of postoperative complications decreases by 7.2%, and the duration of hospitalization is reduced by 3-4 days.

Further accumulation of experience is necessary to confirm the feasibility and effectiveness of this algorithm.