Close up of a Doctors chest with pens in coat pocket and stethoscope around neck.Colorectal cancer is one of the most common types of cancer.

With an estimated 135,430 new cases diagnosed in 2017. It is also the second most deadly cancer in the United States, causing 50,260 deaths last year.

The chances of colon-cancer survival is higher the sooner it can be detected. Regular testing can reduce the risk of colon cancer, while staying aware of symptoms and risk factors is also important.

Here are eight symptoms of colon cancer that you should not ignore.

1. Long-lasting changes in bowel habits

A common symptom of colon cancer is unexplained constipation, or passing stools that are much narrower than usual. A tumor in the colon may be the cause of these symptoms. While not everyone wants to look at their stools, it can become a potentially life-saving habit.

Everyone’s bowel habits and stool quality are different. If your normal habits change for unexplained reasons, ask your doctor about possible causes.

2. Rectal bleeding, blood in your stool, or dark stools

Passing blood is a key symptom of colon cancer, possibly causing dark stools, blood in the toilet, or seeing blood on your toilet tissue. The blood may appear bright red, dark maroon, or even black in the stool. Rectal bleeding may be intermittent, making it easy to ignore, but it is always something to ask your doctor about.

3. Iron-deficiency anemia

Even if you don’t notice it in your stool or toilet, the internal bleeding caused by colon cancer can lead to anemia due to the loss of iron in the blood. When you have a routine blood test, make sure you are tested for iron levels and anemia if colon cancer is a concern. Unexplained blood loss can indicate a serious problem.

4. Unexplained weakness or fatigue

Weakness and fatigue that cannot be explained by other causes, such as insomnia or a virus, can be another indication of anemia related to the rectal bleeding associated with colon cancer. If you experience persistent, unusual fatigue or muscle weakness, especially when accompanied by any of the other symptoms listed here, schedule an appointment with your doctor to determine the cause.

5. Unintentional weight loss

Losing a significant amount of weight without much effort or any deliberate lifestyle changes is usually a sign of something serious. Many varieties of cancer can cause unexplained weight loss. The National Institutes of Health note that cancer can not only affect the appetite, but also interfere with the body’s ability to absorb nutrients from food. This can lead to weight loss or malnutrition.

6. Feeling that your bowel doesn’t empty

Besides internal bleeding and constipation, a tumor in the colon and rectum can also cause a feeling like you need to have a bowel movement, but nothing comes out. This is known as tenesmus, and it may also cause a feeling of needing to strain to pass stools, as well as rectal pain.

7. Cramping or abdominal pain

Stomach pain or cramping that cannot be explained may be another sign of colon cancer. Tumors can not only cause blockages that lead to cramps and constipation, but also cause internal damage. Sharp pain can be a good indication that the internal damage may have caused a perforation.

8. Symptoms plus risk factors

The symptoms of colon cancer may be caused by other conditions, such as an infection, hemorrhoids, or irritable bowel syndrome. Because of this overlap in symptoms, it’s important to understand the common risk factors of colon cancer. When you ask your doctor about colon cancer, make sure she or he knows whether any of these other risk factors apply to you:

  • Age of 50 or older
  • African-American race
  • Personal history of colorectal polyps
  • Inflammatory intestinal conditions, such as ulcerative colitis or Crohn’s disease
  • Family history of colon cancer or genetic mutations that increase cancer risk
  • Consumption of a low-fiber, high-fat diet
  • Sedentary lifestyle
  • Diabetes
  • Obesity
  • Smoking history
  • Heavy alcohol use

Although everyone experiences digestive and bowel irregularity at one time or another, a key indication of colon cancer is the persistence of these changes. Narrow stools that last for only a day or indigestion after a single meal are probably less cause for concern than if these problems become a “new normal” for you.

When in doubt, however, you should always check with your healthcare provider.

Dr. Lynn M. O’Connor dedicates her practice to providing the foremost treatment, technology, and information related to preventive public health issues and colon and rectal health. An outstanding surgeon and health advocate, Dr. O’Connor is also the Director of the Women’s Colorectal Care Program for ProHEALTH Care Associates in the Greater New York City area. Click HERE to contact Dr. O’Connor’s office, or to schedule an appointment.

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