Warning Signs of Cancer

Reviewed/Revised Jul 2023
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Some symptoms can be warning signs of cancer. Most of the time, people who have these symptoms don’t have cancer. But because cancer is more likely to be cured if doctors find it early, it's important to tell your doctor if you have any warning signs.

What are the warning signs of cancer?

Go to a doctor if you have these warning signs of cancer—treatment works best when started early:

  • Weight loss for no known reason

  • Tiredness and fatigue

  • Night sweats

  • Not being hungry or eating as much

  • New pain that doesn't go away

  • A feeling of sickness to your stomach (or throwing up) that keeps coming back

  • Blood in your urine or stool (poop)

  • Change in your stool (too hard or too loose)

  • Fever that keeps coming back

  • Cough that doesn't go away

  • Changes in the size or color of a mole

  • Spot on your skin that doesn’t heal

  • Larger than normal lymph nodes (hard bumps under your arms or in your neck)

  • A lump in the breast

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