The short answer
Cancer can cause many different signs and symptoms, but most of these symptoms are caused by something other than cancer. Knowing the common warning signs helps you notice changes early and decide when to see a doctor.
Cancer can cause many different signs and symptoms depending on where it is.
Most symptoms that could signal cancer are actually caused by something less serious.
Common warning signs include a lump, unexplained weight loss, fatigue, and unusual bleeding.
A symptom that is new, lasting, or unusual for you is the most important reason to get checked.
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The full explanation.
The simple version
Cancer can cause many different signs and symptoms, and they depend on where the cancer is and how big it is. The important thing to know is that most of these symptoms are caused by something other than cancer — but because some can be warning signs, it is worth getting new or lasting changes checked.
Common warning signs
Signs worth paying attention to include:
- A new lump or swelling anywhere on the body
- Unexplained weight loss
- Ongoing tiredness that rest does not fix
- Unusual bleeding or bruising
- A sore that does not heal
- A change in bowel or bladder habits
- A cough or hoarseness that will not go away
- A change in a mole or patch of skin
What to watch for
You do not need to memorize every symptom. The pattern that matters most is a change that is new, that lasts more than a couple of weeks, that keeps getting worse, or that is unusual for you.
A new, lasting, or unusual change is the signal to get checked — not any single symptom.
When in doubt, ask
Only a doctor can find the cause of a symptom. Getting new or lasting symptoms checked early gives you peace of mind if it is nothing, and the best chance to act early if it is something.
Words to know
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Common questions
▸What are common warning signs of cancer?
Common possible signs include a new lump, unexplained weight loss, ongoing fatigue, unusual bleeding, a sore that does not heal, a change in bowel or bladder habits, a nagging cough, or a change in a mole. Any of these can also be caused by other conditions.
▸Do these symptoms mean I have cancer?
Usually not. Most of these symptoms are caused by something other than cancer. But because they can be signs of cancer, new or lasting ones should be checked by a doctor.
▸Which symptoms matter most?
A symptom that is new, lasts more than a couple of weeks, keeps getting worse, or is unusual for you is the most important reason to see a doctor.
▸Why get symptoms checked early?
Finding cancer early, when it is small and has not spread, often makes it easier to treat. Getting new or lasting symptoms checked promptly gives you the best chance to act if something is wrong.
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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