Breast pain

Hormonal changes related to menstrual periods, pregnancy, or use of hormonal medications

Cysts

Fibrocystic changes

Breast infections*

Large breasts that stretch supporting tissues

Very rarely, breast cancer (breast cancer does not usually cause pain)

Pain that occurs throughout both breasts is usually caused by hormonal changes related to menstrual periods.

Breast lumps

Fibrocystic changes

Cysts

Fibroadenomas

Galactocele (a clogged milk duct)

Breast infections, including abscesses*

Scar tissue that develops after an injury

Breast cancer

Lumps in the breasts are relatively common and are usually not cancerous.

Because cancerous and noncancerous lumps are hard to distinguish when a doctor does a breast examination, additional tests are usually done.

Nipple discharge

Most commonly, noncancerous milk duct tumors (intraductal papilloma)

Fibrocystic changes

Breast cancer

Breast infections, including abscesses*

Other disorders, such as pituitary, brain, or thyroid disorders)

Certain medications (see table Some Causes and Features of Nipple Discharge)

A nipple discharge occurs normally sometimes—for example, during milk production after childbirth.

Bloody discharge or discharge from only one breast are the most likely to be signs of breast cancer.

Abnormal discharges vary in appearance depending on the cause.