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Warning Signs You Have Cancer Right Now

If you experience these symptoms, see a doctor.
FACT CHECKED BY Emilia Paluszek

Cancer is a leading cause of death in the US, but with early screening many cancers can be effectively treated. "Identifying cancer in its earlier stages offers improved chances for treating it before it can grow and spread," says Dr. Brian Wolpin, director of the Gastrointestinal Cancer Center at Harvard-affiliated Dana-Farber Cancer Institute. Here are five warning signs of cancer never to ignore. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.



woman touches her bruised knee

Are you suddenly bruising a lot more easily and more often? "Bumping into the edge of the table may result in a bruise — that's normal," says Cleveland Clinic. "But if you have certain blood cancers, you may start to notice bruises in abnormal spots on your body."


Unexplained Fatigue

Woman lying at bed.

Everyone, no matter the state of their health, gets tired once in a while—but sudden fatigue is a red flag for certain types of cancer. "A sudden, lasting change in your energy level, no matter how much sleep you've been getting, can be a sign of leukemia or lymphoma," says the University of California San Francisco Health.


A Lump Or Swelling

breast cancer

Never ignore a lump or swelling on the body, doctors warn. "Most malignant breast lumps are not painful, and sometimes it's difficult for a woman to tell the difference between a cancer and a non-cancer lump, so one must get to know her breast," says Beth Overmoyer, MD. "I'm a firm advocate in self-breast exams because cysts are very prevalent, and a woman needs to know what is a cyst and what has been there for a long time. If you notice a change in the lump, that should bring you to the physician."


An Itchy Mole

Girl with birthmarks on the neck

Keep an eye on changes in skin, especially moles—if they change color and start to itch or bleed, it could be a sign of something serious. "We think that some of that irritation — the itching, the bleeding — is actually the body starting to recognize [the cancer] and starting to attack it a little, making it irritated," says Elizabeth Buchbinder, M.D., an oncologist at the Dana-Farber Cancer Institute in Boston and an assistant professor at Harvard Medical School. "And so that's why you'll see some itching and bleeding and irritation near the actual mole."


Unexplained Weight Loss

weight loss

Sudden, unexplained weight loss is a common sign of cancer, doctors say. "In studies that examined the causes of unintentional weight loss, 5 to 37 percent of patients were eventually diagnosed with cancer," says Dr. Richard Levine, medical director at Moffitt Cancer Center at International Plaza. "But it is not always indicative of cancer, and there are many other causes."

Ferozan Mast
Ferozan Mast is a science, health and wellness writer with a passion for making science and research-backed information accessible to a general audience. Read more about Ferozan
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