Breast cancer occurs when abnormal cells grow out of control
in one or both breasts. They can invade nearby tissues and
form a mass, called a malignant tumor. The cancer cells can
spread (metastasize) to the lymph nodes and other parts of
the body. Risk factors that you cannot change include getting
older and having changes to certain genes. Risk factors you can
change include using certain types of hormone therapy after
menopause, being overweight, and not getting enough physical
activity.
Breast cancer can cause:
- A change in the way the breast feels. The most common
symptom is a painless lump or thickening in the breast or
underarm.
- A change in the way the breast looks. The skin on the breast
may dimple or look like an orange peel.
- A change in the nipple. It may turn in. The skin around it may
look scaly.