Colon cancer is among the most common cancers in America, with approximately 106,000 new cases reported in the United States each year, according to American Cancer Society. The good news: it’s often easy to treat when caught in the early stages – which is why it’s so important to be aware of any potential symptoms of colon cancer. And what signs do people often miss?
But what are these symptoms?
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The Top Colon Cancer Sign People Often Reject
Rectal bleeding is among the most common early signs of colon cancer. “Bleeding is the main symptom,” says Dr. Robert E. Schoen, MDgastroenterologist at UPMC.
While rectal bleeding can be hard to miss, people often assume it’s caused by something less serious. “People have some rectal bleeding and they think, ‘Oh, it’s hemorrhoids.’ There is nothing to worry about.’ And that can be a fatal mistake,” says Dr. Shoe. “Because it’s not always hemorrhoids. It could be something bad, like cancer, and it needs to be treated and evaluated.”
Dr. Arielle Kanters, MD, a colorectal surgeon at the Cleveland Clinic, agrees that this is not something people should just brush off without consulting a doctor. “Rectal bleeding without a clear source and without a recent colonoscopy — at least in my mind as a colorectal surgeon — is (possible) cancer until proven otherwise,” says Dr. Edges.
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Other commonly overlooked signs of early colon cancer
The other common early colon cancer symptom that many people overlook – or ignore – is a change in bowel habits. “It can either be going from where you were regular and now you’ve got increasing constipation, or the flip side, a change to diarrhea symptoms,” says Dr. Shoe.
Since bowel patterns can fluctuate for a wide variety of reasons, says Dr. Schoen that the key is to keep an eye out for ongoing problems with no obvious cause. “If you go on vacation and you get constipated, that doesn’t mean you need to rush to your doctor. You want to see some persistence of the symptoms.”
Dr. Kanters says there are other symptoms that could be a potential sign of early colon cancer. “Other common symptoms would be unexplained weight loss and unexplained anemia – so low blood counts, really tired and losing energy. And changes in the color of your stool. Not just turning bright red, but turning dark black can also be a sign of blood loss, though it’s not the normal color we think of.”
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Why routine screenings are so important
Doctors emphasize that ideally, you want to catch colon-related problems before they even cause noticeable symptoms, and well before they ever reach the point where they become cancerous. That American Cancer Society report that colon cancer diagnosis rates have been declining over the past few decades, in part due to the increase in screenings.
“You need to go get yourself screened,” says Dr. Shoe. “It’s the best way to protect yourself from getting and, God forbid, dying from colon cancer.”
He notes that colon cancer screenings can not only detect and diagnose cancer, but can often prevent cancer from developing in the first place. Growths called polyps, some of which may be pre-cancerous, can often be removed during a colonoscopy. This preventive approach is the best possible outcome, doctors say. “We always say the best cancer is a cancer you don’t get,” says Dr. Shoe.