Breast Cancer

The breast is made up of different tissues, ranging from very fatty tissue to very dense tissue. Within this tissue is a network of lobes. Each lobe is made up of small, tube-like structures called lobules that contain milk glands. Small ducts connect the glands, lobules, and lobes, carrying milk from the lobes to the nipple. The nipple is located in the middle of the areola, which is the darker area that surrounds the nipple.

Blood and lymph vessels also run throughout the breast. Blood vessels nourish the cells by delivering oxygen and nutrients and also removing waste and carbon dioxide. Lymph vessels, unlike blood vessels, only carry fluid away from tissues. They connect to lymph nodes and the lymphatic system, which drains bodily waste products. Lymph nodes are the small, bean-shaped organs that are part of the body's immune system and help fight infection. Groups of lymph nodes are located in different areas throughout the body, such as in the neck, groin, and abdomen. Regional lymph nodes of the breast are those nearby the breast, such as the lymph nodes under the arm, which are called axillary lymph nodes.