Two young women sitting at a desk reviewing a book

A quick definition

Colorectal cancer is the third most common cancer diagnosis, excluding skin cancers, by the American Cancer Society (ACS). Colorectal cancer is also referred to as colon or rectal cancer, depending on where the cancer has started to grow within the large intestine. These cancers typically start as a polyp growing on the inner-most wall of the large intestine; over time a precancerous polyp can evolve into a cancerous tumor or mass, which can then spread from the colon or rectum. The level of advancement of colorectal cancer, or “stage”, is determined by how deep that cancerous mass invades within the intestinal wall and the extent of its spread through the body.

Age differences and risks

One of the keys to decreasing the severity of cancer is early identification. For colorectal cancer, removal of a precancerous polyp can prevent it from becoming a cancerous tumor. While clinical screening guidelines have been evolving over the last few decades, the ACS currently recommends that patients with “average” risk for colorectal cancer begin screenings at age 45. These screenings have been attributed to a decrease in the overall number of colorectal cancers in patients over the age of 50.

Early-onset colorectal cancer in those under the age of 50 is, however, rising rapidly according to the National Cancer Institute. ACS research supports this perspective, identifying a consistent 1-2% increase in colorectal cancer cases among young adults each year since the mid-1990s. The rapid rise in colorectal cancer in younger adults can't clearly be explained and research on unique, age specific risk factors still needs to occur.

Regardless of age, there are a number of general risk factors for colorectal cancer that lifestyle changes can impact. These risk factors include:

  • a diet high in red meats and processed meats or low in fruits and vegetables
  • excessive drinking
  • lack of exercise
  • obesity
  • tobacco use

Additional risk factors include a history of inflammatory bowel disease (such as Crohn’s or ulcerative colitis); a family history of colorectal cancer or colorectal polyps; and certain inherited genetic conditions, such as Lynch syndrome and familial adenomatous polyposis. The ACS also notes that people of Native American / Alaskan Native descent have a higher incidence of colorectal cancer rate than people of other racial groups.

Warning signs

In most cases, colorectal cancer can occur in adults without any detectable symptoms, making screening and expert diagnosis even more critical to your health and wellbeing. Nevertheless, there are some symptoms or warning signs of colorectal cancer that every adult should know:

  • Bright red, black, or tarry blood in stool
  • Consistent feeling of fatigue
  • Constipation, diarrhea, or a feeling of having an unemptied bowel
  • Discomfort in the abdominal area, including:
    • Bloating
    • Cramps
    • Frequent gas pains
  • Unexpected weight loss
  • Unusually narrow stools

If you are experiencing these symptoms, you should talk to your doctor.

Our fight against colorectal cancer starts with you.

The colorectal cancer risk assessment is a free, confidential tool that can help identify your risk for colorectal cancer. This assessment can be completed in about 10 minutes, and your results are available immediately. Your email address will not be shared with anyone, but will be used to send a copy of your results and offer next steps in your colorectal health journey.

Understanding your risk for colorectal cancer can help you talk with your primary care provider about your risk, early screening, or any necessary lifestyle changes.