Breast Anatomy and Nipple Aspirate Fluid (NAF) Collection

The female breast has two main components; glandular tissue (lobes and ducts) and connective tissue. The breast is divided into 5 to 7 lobes that radiate outwards from the nipple and contain clusters of milk-producing glands. The lobes are further divided into smaller compartments called lobules. Each cluster drains into a duct, which connects the lobules and the nipple. The breast is held together by fatty connective tissue, which provides support and contains nerves as well as blood and lymphatic vessels.

Cancer is the term for an uncontrolled growth of glandular tissue. Over 85% of breast cancers start in the lobules or the ducts. Those that originate in lobules are known as lobular carcinoma while those that begin in ducts are called ductal carcinomas. The term “noninvasive breast cancer” refers to cancers that are early and confined to lobules or ducts. Another term used to describe these cancers is in situ. Invasive breast cancer refers to a carcinoma that has spread from lobules or ducts to fatty connective tissue or beyond.

It has been known since early studies in the 1950s by Dr. George Papanicolaou, the inventor of the “Pap smear” for cervical cancer, that adult non-pregnant, non-lactating women secrete fluid into the milk ducts of the breast. The MASCT System device (shown below) is approved by the FDA as a method to collect this fluid.