Breast cancer begins in the breast tissue. It is characterized by the uncontrolled growth and spread of abnormal cells, which usually starts in the milk sacs or ducts. The tumour may be hard or soft and may sometimes be described as a thickening of the breast. Breast cancers are almost always painless.
Breast cancer is the most common cancer among women, other than skin cancer. It rarely affects men. One woman in nine will develop breast cancer during their lifetime. It is the second leading cause of cancer deaths in women, after lung cancer. It is the leading cause of cancer death among women aged 40 to 55.
The Canadian Cancer Society estimates that in 2011, an estimated 23,400 women will be diagnosed with breast cancer and 5,100 will die of it.
What causes breast cancer? | Types of breast cancers | Benign breast tumours |
Structure of the breast | Prevention | Tests - if cancer is suspected | Diagnosis |
Treatment Options | Surgery for breast cancer | Living with breast cancer