Breast ductal lavage (DL) and fiberoptic ductoscopy (FDS) are used to evaluate patients at risk for breast cancer. DL involves collection of breast ductal epithelial cells for cytological analysis, and FDS involves direct visualization of the breast duct lining with cytology or biopsy of abnormalities. These procedures are intended to be used in conjunction with clinical breast examination and mammography for the early detection and pathological diagnosis of nonpalpable breast cancers and precancerous lesions in high-risk women with normal or indeterminate findings by radiological and physical examination. The early detection of breast cancers and precancerous lesions has the potential to allow for timelier decision-making regarding further diagnostic testing, monitoring, prevention, and treatment.