Glossary of Medical Terms

Breast Cancer

Breast cancer is the most common cancer occurring in women (excluding cancers of the skin) and the second most common cause of death from cancer in women after lung cancer. Men can also develop breast cancer, but male breast cancer is rare, accounting for less than 1% of all breast cancer cases. If diagnosed at an early stage, breast cancer has an encouraging cure rate: up to 97% of women diagnosed with localized breast cancer will survive five years after their diagnosis. Even if the cancer is found at a more advanced stage, new therapies have enabled many people with breast cancer to experience a good quality of life.

The breast is comprised mainly of fatty tissue. Within this tissue is a network of lobes, which are made up of tiny, tube-like structures (called lobules) that contain milk glands. Tiny ducts connect the glands, lobules, and lobes and carry the milk from the lobes to the nipple, located in the middle of the areola (darker area that surrounds the nipple of the breast). Blood and lymph vessels run throughout the breast; blood nourishes the cells, and the lymph system drains bodily waste products.