A potentially malignant breast lump (cancer) may show a number of these symptoms:

• breast mass found during self-examination -- usually painless, firm to hard, with irregular borders
• spontaneous nipple discharge -- usually bloody or serous (straw-colored fluid)
• nipple changes -- retraction, enlargement, or itching
• breast asymmetry aside from the previous norm
• skin changes
  • dimpling, retraction, "orange peel" appearance
  • redness, accentuated veins on breast surface and eventually, with late disease, skin ulceration
• bone pain
• weight loss
• armpit lump
• swelling of the arm

Benign fibrocystic changes may range from mild to severe during the menstrual cycle. Symptoms typically peak just before each menstrual period and improve immediately after the menstrual period. The breast tissue has a dense, "cobblestone" consistency, usually more marked in the outer quadrants. An intermittent or persistent sense of breast "fullness" with dull, heavy pain and tenderness is experienced.

Benign fibrocystic changes frequently are noted in both breasts. Benign lumps are usually rounded with smooth borders, either rubbery or slightly movable, and non-anchored. Associated nipple discharge occurs only after manipulation of the nipple, is milky looking, and may be expressed from both breasts.

For a potentially malignant breast lump (cancer), the health care provider confirms the breast changes noted by the patient by performing a physical exam. There may be spontaneous nipple discharge on one side from a single duct. Armpit (axillary) node enlargement/tenderness may be noted.

A mammography may delineate the breast mass. A needle aspiration does not yield fluid consistent with a cyst and the mass persists after aspiration. An ultrasound may be performed to differentiate between a solid and cystic mass. Cancer more commonly shows a solid mass.

A biopsy can confirm or rule out suspected cancer in solid lumps:

• needle biopsy -- removal of cells for evaluation directly from the mass (can be done in conjunction with needle aspiration procedure)
• incisional biopsy -- surgical removal of a portion of the mass for evaluation
• excisional biopsy -- surgical removal of entire mass for evaluation