§ Ductal lavage. In this procedure, your doctor inserts a tiny, flexible tube (catheter) into the lining of a duct in your breast — the site where most cancers originate — and withdraws a sample of cells. The cells are then examined for precancerous changes that might eventually lead to disease. These changes may show up long before tumors can be detected on a mammogram. But because ductal lavage is a new and invasive procedure, many unknowns remain, including the rate of false-negative results, the exact location in the breast of abnormal cells and whether those cells will necessarily lead to cancer. Clinical trials are being conducted to help find the answers to these questions. In the meantime, ductal lavage isn't recommended as a screening tool.
§ Molecular breast imaging (MBI). This experimental technique tracks the movement of a radioactive isotope injected into the bloodstream and taken up by breast tissue, particularly tumors. In preliminary studies, MBI found small tumors that both mammography and ultrasound missed. It's not yet clear how any abnormal findings from MBI could be biopsied, but this is an area of study. Besides requiring some radiation, this imaging method also involves slight compression of the breast. This imaging technique is being studied in women with dense breast tissue and women at high risk of breast cancer. Depending on study results, MBI would most likely become an adjunct to — but not a replacement for — mammography.