What is Breast Cancer?

The breast is made up of millions of cells.  Breast cancer develops when one of these cells begins to muliply out of a control and forms a tumour.

Some cancer cells may break away and travel to other parts of the body forming secondary tumours.

The breast consists of fatty tissue and lobules that are connected to the nipples by ducts.  Breast cancer usually starts in a cell lining, a duct or a lobule.

Source: Breast Cancer Briefsheet: Cancer Research UK: July 2008