What is Breast Cancer?

Before we investigate breast cancer, let’s take a moment to explore the basic anatomy of the female breast. The complex structure of the breast includes:

  • Lobules – These are milk-producing glands that branch out from the nipple. Each lobule is made up of small sacs called alveoli.
  • Ducts – These tiny tubes transport milk from the lobules to the nipple.
  • Stroma – This is the space around the lobules and ducts that is composed of connective tissue and fatty tissue.
  • Arteries – These thin blood vessels carry nutrients and oxygen to the breast tissue.
  • Lymph Nodes – The lymphatic system is a collection of small nodes (bean-shaped cells) that contain tissue, fluid and waste products. Lymph nodes are located behind the breast bone, in the armpit, below the collarbone, in the groin area and in other parts of the body.

Most types of breast cancers start in the ducts of the breast; however, there are some that start in the lobules and other surrounding tissues. These malignant cells invade other cells and form tumors. If breast cancer reaches the lymphatic system, there is a greater risk that it has spread to other parts of the body through the bloodstream – a process known as metastasis.