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Colon Cancer Signs to Watch For Now, Say Doctors

Catch the crucial SOS signals before it's too late.
Colon, or colorectal cancer, is any cancer involving the large intestine and/or rectum, and can be as painful as that sounds. "Sometimes abnormal growths, called polyps, form in the colon or rectum. Over time, some polyps may turn into cancer," says the CDC. Here are the signs and symptoms of colon cancer you need to look out for. Read on—and to ensure your health and the health of others, don't miss these Signs Your Illness is Actually Coronavirus in Disguise.


Silent Sign: Diarrhea

woman hand flush toilet after using

"Tumors in the right-colon are likely to bleed and cause diarrhea," explains Dr. Beatriz Amendola of Innovative Cancer Institute in Miami, Fl. She points out that younger patients are more likely to be misdiagnosed for IBS irritable bowel syndrome (IBS). 


Silent Sign: Constipation

A man holding his stomach.

"As the tumor grows it can cause the diameter of the colon to become smaller and smaller making it harder to pass stool through the colon," explains Kristina Booth, MD, OU Medicine colorectal surgeon. "This can result in less frequent bowel movements and in some cases narrowing of the stool, too."


Silent Sign: Thin, Bloody Stools

upset woman in toilet by diarrhea, constipation, hemorrhoids, piles

In addition to constipation and diarrhea, any other changes in stools can be a sign of colon cancer. Steven Reisman, MD, Director of New York Cardiac Diagnostic Center, specifies that narrow or thin stools or those with blood in them (red or black) are things to look out for. "These symptoms can represent a tumor blocking the colon or bleeding into the colon," he explains. 

The Rx (Unusual BMs): If you notice any abnormality in your stool—especially blood—you should see a gastroenterologist and arrange a colonoscopy. And if you do receive an IBS diagnosis and your bowel movements don't seem to improve after treatment, go back for a second opinion.


Silent Sign: Hard Belly Button Lump

Senior man with stomach pain

If you notice any hardness around your belly button, do not ignore it. "A hard knot at the belly button could be a Sister Mary Joseph node," explains Dr. Booth. In addition to being a sign of colon cancer, it could also be a sign of another cancer in the abdomen, that has spread outside the colon.

The Rx: Since this symptom can imply a variety of cancers, call your physician as soon as you notice hardness at the belly button. 


Silent Sign: Iron Deficiency and Anemia

Laboratory assistant with a sample of blood in a test tube

Anemia, or a lack of iron, can be a symptom of colon cancer. "This is due to the gradual loss of blood in the stool," says William Tierney, MD, OU Medicine gastroenterologist. "The bleeding very slow and is not visible in the bowel movement so it is silent but occurs continuously over months to years leading to depletion of the body's iron stores." 

The Rx: Stay up to date on your blood work. "Iron deficiency in any male and any non-menstruating female warrants a search for blood loss in the gastrointestinal tract and colon cancer is a common cause," Dr. Tierney says. 


Silent Sign: Unexplained Weight Loss

woman disappointed after checking weight

If you are losing weight and have no explanation for it, it could be a sign of a variety of different cancers—including colon. If you have any other symptoms—especially a change in stools—you shouldn't ignore the numbers going down on the scale, says Dr. Reisman. 

The Rx: "Consult a physician for an evaluation for weight loss," instructs Dr. Reisman.


Silent Sign: Abdominal Cramping or Pain

Man hugging his belly and keeping eyes closed while lying on the couch at home

If you are feeling discomfort, pain, or cramping in your midsection and it won't seem to go away, you shouldn't ignore it. "If this lasts for a significant amount of time (more than a week) or gets progressively worse it may represent a tumor in the colon," explains Dr. Reisman. 

The Rx: Pain and cramping in the abdominal region can represent a variety of health issues. Dr. Reisman suggests making an appointment with your gastroenterologist to schedule a colonoscopy to rule out colon cancer.


Silent Sign: Unexplained Loss of Appetite

Displeased young woman doesn't want to eat her breakfast

While losing your appetite for no explainable reason could be due to so many health issues or cancer, if it is paired with other colon cancer symptoms—especially changes in bowel habits—it shouldn't be overlooked. 

The Rx: "One should see a physician to get blood tests and determine if a colonoscopy is warranted," Dr. Reisman urges. 


Silent Sign: Weakness and Fatigue

tired man

Weakness and fatigue may be a really common part of your day. However, they can be symptoms of iron deficiency anemia, a symptom of colon cancer, reminds Dr. Reisman. 

The Rx: If you are feeling tired and weak all the time, you should make an appointment with your MD to have blood work done. While anemia in and of itself isn't a huge concern, it could be a symptom of a greater health issue—such as colon cancer. 


What to Do if You Experience These Symptoms

Doctor and senior man wearing facemasks during coronavirus and flu outbreak

If any of these signs or symptoms are present, it is imperative that you discuss with your primary or seek immediate medical attention. "Your doctor will likely order testing if you have any of the aforementioned complaints but in many cases you will need to have a colonoscopy for further evaluation," explains Dr. Masoud. "This procedure is very safe and represents the mainstay of cancer detection and prevention."


What to Do: Early Detection Is Key

patient with doctor

As with most health complications and especially cancer, early detection can be the key to a favorable outcome and eventual successful therapy. "As always, the best protection against cancer is prevention," Amir Masoud, MD, a gastroenterologist, explains to Eat This, Not That! Health. "Non invasive screening tests and colonoscopy have lead to a significant reduction in cancers and related deaths. It is imperative that we follow screening recommendations and do not neglect symptoms or signs that could point to something more going on."


What to Do: A Colonoscopy Can Help

Gastrologist. Doctor's office. Doctor gastroenterologist with probe to perform gastroscopy and colonoscopy

The best way to detect colon cancer early is colonoscopy. "Colonoscopy has been routinely recommended to be done every 10 years starting at age 50," explains Matthew Mintz, MD, FACP. People with other risk factors, such as a first degree relative who had colon cancer, can be screened even earlier. "Colonoscopy is excellent for identifying pre-cancerous polyps, which are small, early growth that haven't become cancer just yet," he says.

The gastroenterologist who performs the colonoscopy sees these pre-cancerous polyps and removes them-cancer averted, life-saved. "The problem is that most people decide not to do the colonoscopy because they are afraid of the procedure or they find it inconvenient," he points out.


What to Do: Try Cologuard

Cologuard box
Courtesy of Cologuard

Cologuard is a new test which looks for cancer DNA in your stool, Dr. Mintz points out. "It is easy and convenient, and it is almost (about 90%) as good as colonoscopy," he says. While he doesn't endorse it as the preferred screening method for patients, "it is certainly much better than not doing anything, and thus a reasonable alternative for patients who want to avoid a colonoscopy."


What Are the Chances You Will Get Colon Cancer?

Woman holding model of human intestines in front of body.

Unfortunately, it is very common, with almost 150,000 new cases diagnosed each year. "In the United States, it remains the second most lethal cancer in men and third most in women," explains Dr. Masoud. "While the incidence of colorectal cancer has declined in people over the age of 50—thanks to effective screening programs—we are seeing an uptick in new cases involving younger patients."


Can You Spot Colon Cancer Symptoms in the Early Stages?

Health visitor and a senior man during home visit

Usually symptoms do not present themselves until colon cancer is in more advanced stages, although a colonoscopy before it starts to cause symptoms can help. "It is therefore imperative that we are aware of the possible warning signs and seek immediate medical attention if any of these are present," explains Dr. Masoud. And to get through this pandemic without catching coronavirus, don't miss this essential list: Things You Should Never Do Before Your Vaccine.

Leah Groth
Leah Groth has decades of experience covering all things health, wellness and fitness related. Read more about Leah
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