Ductal lavage is a screening method used in at-risk women for breast cancer detection. In this method, cells are collected from milk ducts in the breast. The procedure involves inserting a catheter (tube) into the nipple, which releases a small amount of salt water into the duct. The water picks up breast cells and the entire fluid is then retrieved and sent to be examined for cells, which are checked under a microscope. Apart from clinical breast examination and mammography, ductal lavage can also be used to detect breast cancer.