The short answer
Most breast lumps are not cancer. Common causes include cysts, fibroadenomas, and normal hormonal changes. Still, because some lumps are breast cancer and it is very treatable when found early, any new breast lump should be checked by a doctor.
Most breast lumps are not cancer — often cysts or benign changes.
Breast tissue normally feels lumpy and changes with the menstrual cycle.
Any new, distinct, or persistent breast lump should be checked.
A hard, painless lump, skin changes, or nipple discharge is more worth checking.
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The full explanation.
The simple version
Finding a breast lump is frightening, but most breast lumps are not cancer. Cysts (fluid-filled sacs), fibroadenomas (smooth, movable lumps), and normal hormonal changes are common. Still, because some lumps are cancer, and breast cancer is very treatable when caught early, any new lump should be checked.
What usually causes breast lumps
Breast tissue is naturally lumpy and often changes with the menstrual cycle, becoming more tender or lumpy before a period. Cysts and fibroadenomas are common benign lumps. These causes are frequent and usually harmless.
What makes a lump more worth checking
A lump is more worth prompt checking when it is new and does not go away after a menstrual cycle, feels hard or fixed, or comes with skin dimpling, nipple changes or discharge, or swelling in the armpit. These can have benign causes too, but they should be evaluated.
When to see a doctor
See a doctor about any new breast lump, especially one that persists beyond a cycle or comes with skin or nipple changes. Keep up with recommended mammograms, which can find breast cancer before a lump can be felt.
Words to know
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Common questions
▸Are most breast lumps cancer?
No. Most breast lumps are cysts, fibroadenomas, or normal hormonal changes. Only a minority are cancer, but any new lump should be checked.
▸What breast lump is more worth checking?
A new lump that persists beyond a menstrual cycle, feels hard or fixed, or comes with skin dimpling or nipple changes.
▸Breast tissue feels lumpy in general — is that normal?
Yes. Breast tissue is naturally lumpy and changes with the cycle. It is a new or distinct lump that is worth checking.
▸Should men check for breast lumps too?
Yes. Breast cancer is uncommon in men but possible, so any new breast lump in a man should also be checked.
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