Possible causes of benign breast lumps include fi. Similar to how the blood circulatory system distributes elements throughout the body, the lymph Breast tissue fat transports disease-fighting cells and fluids. The spaces around the lobes and ducts are filled with Breast tissue fat tissue and ligaments. Understanding the different parts and functions will help you better grasp the details of breast cancer. A healthy female breast is made up of 12—20 sections called lobes. Adipose tissue The female breast is mostly made up of a collection of fat cells called adipose tissue.