Colon & Rectal Cancer

Colorectal cancer is the fourth most commonly diagnosed cancer and the second leading cause of cancer death in men and women in the United States. The American Cancer Society estimates that almost 150,000 people are diagnosed with colorectal cancer a year.

Colorectal cancer is cancer that develops in the tissues of the colon or rectum. The colon and the rectum are both found in the lower part of the digestive system. They form a long, muscular tube called the large intestine (or large bowel).

If the cancer began in the colon, which is the first four to five feet of the large intestine, it may be referred to as colon cancer.

If the cancer began in the rectum, which is the last several inches of the large intestine leading to the anus, it is called rectal cancer.

If caught early, colorectal cancer is a highly treatable and often curable disease when localized to the bowel. 

Risk Factors

Family history and older age are the major risk factors for colorectal cancer.

Several other factors have been associated with increased risk, too, including excessive alcohol use, obesity, being physically inactive and cigarette smoking.

People with a history of inflammatory bowel disease, such as ulcerative colitis or Crohn's disease, also have a higher risk.

Some inherited conditions, such as Lynch syndrome and familial adenomatous polyposis, may also increase the risk of colorectal cancer.

Signs and Symptoms

Early stages of colorectal cancer often have no symptoms.

Some symptoms a person may experience, however, include blood in the stool, diarrhea, constipation or other stool issues, unexplained weight loss, regular episodes of belly pain, nausea or vomiting.

Symptoms can include:

  • A change in bowel habits that lasts for more than a few days, such as diarrhea, constipation or a feeling that your bowel is not empty after a bowel movement
  • Bright red or very dark blood in your stool
  • Constant tiredness
  • Stools that are thinner than normal
  • Ongoing gas pains, bloating, fullness or cramps
  • Unexplained weight loss
  • Vomiting


It is recommended that people at average risk of colorectal cancer get regular screenings beginning at the age of 50.

Screenings should continue to age 75. After age 75, the decision to screen is based on a person’s life expectancy, health status other health conditions and prior screening results.

Routine screening of people age 86 or older is not recommended.

It’s also recommended that people younger than age 45 with a family history of colon cancer or who have inflammatory bowel disease talk to their health care provider about when to begin screenings.

Types of Screening

There are several different kinds of screening tests available, including colonoscopies and at-home tests.

Talk to your health care provider, and together you can make the best decision on the type of screening that’s appropriate for you.

A colonoscopy is generally considered screening when:

  • There's no family history of cancer or polyps
  • You are not experiencing symptoms before the procedure
  • You don't have a personal history of cancer or polyps
  • No polyps, diverticulosis, etc., are found during the procedure

A colonoscopy is generally considered diagnostic when:

  • You have a personal history of cancer or polyps
  • You have a family history of cancer or polyps (some insurances consider this high risk)
  • You are experiencing symptoms before the procedure such as change in bowel habits, rectal bleeding, abdominal pain, etc.
  • The screening procedure finds polyps, cancer, diverticulosis, etc.

Early and regular screening for colon cancer is not just a way to detect cancer, it can be a form of cancer prevention if polyps are discovered early before they become cancerous.

Talk to your health care provider about your screening options - it may save your life.

Comprehensive Care

OSF HealthCare offers a full range of services, diagnostic tests and treatment options, including:

  • Ablation and embolization
  • Colon reconstruction
  • Colonoscopy
  • Computed tomography (CT Scan)
  • Immunotherapy

Are You at Risk for Colorectal Cancer?

Learn when you should be tested for colorectal cancer using our free colorectal cancer risk assessment tool.

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