The short answer
Most lumps people find are not cancer. Common causes include cysts, swollen lymph nodes from infection, and harmless fatty lumps. A lump is more worth checking when it is hard, painless, growing, or does not go away after a few weeks.
Most lumps are not cancer — they are cysts, swollen glands, or fatty growths.
Swollen lymph nodes often appear with colds and infections and settle on their own.
A lump that is hard, painless, fixed in place, or growing is more worth checking.
Any lump that lasts more than a few weeks is worth showing a doctor.
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The full explanation.
The simple version
Finding a lump is alarming, but most lumps are harmless. Cysts (fluid-filled sacs), swollen lymph nodes from infections, and lipomas (soft fatty lumps) are all common and are not cancer.
What usually causes lumps
Swollen glands in the neck, armpit, or groin often flare up with a cold, sore throat, or other infection and shrink as you recover. Cysts and fatty lumps can appear anywhere and are usually soft, movable, and slow to change.
What makes a lump more worth checking
A lump is more worth a doctor's look when it is hard, painless, does not move easily under the skin, is steadily growing, or has been there for more than a few weeks without settling. These features can have harmless causes too, but they are worth checking.
When to see a doctor
See a doctor about any lump that lasts more than about two to three weeks, is growing, feels hard or fixed, or worries you. Showing it to a doctor early is sensible, and most of the time the explanation is reassuring.
Words to know
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Common questions
▸Are most lumps cancer?
No. Most lumps are cysts, swollen lymph nodes, or harmless fatty growths. Only a minority turn out to be cancer.
▸What kind of lump is more concerning?
A lump that is hard, painless, fixed in place, steadily growing, or lasts more than a few weeks is more worth checking.
▸My lump appeared with a cold — is that normal?
Yes. Swollen lymph nodes commonly appear with infections and usually shrink as you recover. If a node stays swollen for several weeks, get it checked.
▸Should painful lumps worry me more?
Not necessarily. Painful lumps are often from infection or inflammation. A hard, painless lump is actually more worth checking, though any lasting lump deserves a look.
Questions to ask your doctor
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