The short answer
Possible breast cancer signs include a new lump, changes in breast size or shape, skin dimpling, nipple changes, or discharge. Many of these have non-cancer causes, but any new or lasting change should be checked by a doctor.
A new lump in the breast or underarm is the most common sign, but not all lumps are cancer.
Other signs include changes in breast size or shape, skin dimpling, or redness.
Nipple changes, such as turning inward or new discharge, can also be signs.
Many breast changes have non-cancer causes, but new or lasting ones should be checked.
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The full explanation.
The simple version
Breast cancer can cause a lump or other changes in the breast, but many breast changes are not cancer. Knowing the possible signs helps you notice changes early and get them checked. Screening can also find breast cancer before any symptoms appear.
Common signs
Possible signs and symptoms include:
- A new lump or mass in the breast or underarm
- Swelling or a change in the size or shape of a breast
- Dimpling or puckering of the skin
- Redness, thickening, or scaling of the skin or nipple
- A nipple turning inward or new nipple discharge
Not every change is cancer
Many breast changes have non-cancer causes, such as cysts or normal hormonal changes. But because some changes are signs of cancer, it is important to have any new or lasting change evaluated by a doctor rather than waiting.
Any new or lasting breast change should be checked by a doctor.
Screening finds it early
Screening mammograms can find breast cancer before it causes symptoms, when it is often easier to treat. Talk with your doctor about when to start screening and how often, based on your age and risk.
Words to know
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Common questions
▸What is the most common sign of breast cancer?
The most common sign is a new lump or mass in the breast or underarm. A painless, hard lump with irregular edges is more likely to be cancer, but lumps can also be soft, tender, or rounded, so any new lump should be checked.
▸What other symptoms can occur?
Other possible signs include swelling or a change in breast size or shape, skin dimpling or puckering, redness or thickening of the skin, nipple pain or turning inward, and nipple discharge other than breast milk.
▸Do all breast changes mean cancer?
No. Many breast changes are caused by non-cancer conditions. But because some are signs of cancer, any new or lasting change should be evaluated by a doctor.
▸Can breast cancer be found before symptoms?
Yes. Screening mammograms can find breast cancer early, before it causes any symptoms, which is why regular screening is recommended for many people.
▸When should I see a doctor?
See a doctor if you notice a new lump, a change in the size or shape of a breast, skin or nipple changes, or nipple discharge. Getting new changes checked promptly is important.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
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