Statistics on Risk and Surviving Colorectal Cancer

Colon cancer risk factors

The exact cause of colorectal cancer is not known. However, studies show that certain factors are linked to an increased chance of developing the disease. Ongoing research will continue to give us information in the diagnosis and treatment of colorectal cancer.

Who's at risk?

There are a number of personal factors influencing who is more likely than others to develop colon or rectal cancer.
  • Age - Colorectal cancer is more likely to occur as people get older. The average age for developing colorectal cancer is around 60, but risk can begin much earlier.
  • A history of cancer - A person who has already had colorectal cancer is at an increased risk of developing it a second time. Women with a history of ovarian, breast, or uterine cancer have a somewhat increased chance of developing colorectal cancer.
  • A history of polyps - Polyps are growths that protrude from the inner wall of the colon or rectum. They are relatively common in people over age 50. Most are benign (noncancerous). However, some kinds of polyps are more likely to result in the development of cancer than others. Adenomatous polyps are considered the most likely to develop into cancer. Polyps are detected and removed during a colonoscopy.
  • A history of inflammatory bowel disease - Ulcerative colitis is a condition that causes inflammation and sores (ulcers) in the lining of the colon. Crohn's colitis (also called Crohn's disease) causes chronic inflammation of the gastrointestinal tract. People who have ulcerative colitis or Crohn's colitis may be more likely to develop colorectal cancer than people who do not have these conditions.

Risk factors linked to family
  • Family history - You are at increased risk if you have a first-degree relative (father, mother, brother, sister) with a history of either colon cancer or polyps before age 60; or two or more relatives at any age.
  • Familial adenomatous polyposis (FAP) - This is a rare, inherited condition in which hundreds of polyps develop in the colon and rectum. This condition can appear as early as the teen years and is very likely to lead to colorectal cancer.
  • Gardner's syndrome - Like FAP, this hereditary condition results in polyps and colon cancer that develops at a young age. It can also cause noncancerous tumors of the skin, soft connective tissue, and bones.
  • Hereditary nonpolyposis colorectal cancer (HNPCC) - People with this hereditary condition tend to develop cancer at a young age without first having polyps.
  • Ashkenazi Jews - These are Jews from, or whose ancestors are from, Eastern Europe. They have an inherited change in their DNA that causes a slightly increased risk of developing colon cancer.

Lifestyle risk factors
  • Smoking - Recent studies show that smokers are 30 - 40 percent more likely than nonsmokers to die of colorectal cancer.
  • Diet - Some evidence suggests that the development of colorectal cancer may be associated with certain food characteristics. Among populations that consume a diet high in fat, protein, calories, alcohol, and meat, and low in foods with fiber, calcium and folate are at higher risk for colorectal cancer.
  • Exercise - Some evidence suggests that being overweight and living an inactive lifestyle may be associated with an increased risk of colorectal cancer. In contrast, people who exercise regularly may be at lower risk.
  • Alcohol - Heavy use of alcohol has been linked to colorectal cancer. 

Stages of colorectal cancer

Colorectal cancer has five distinct stages, along with a sixth stage called recurring. In the early stages, colon cancer is one of the most curable cancers. 

Below are general descriptions of the stages.

Stage 0 - The cancer involves only the lining, or mucosa, of the colon or rectum and is confined to polyp(s). When the polyps are removed during a colonoscopy, the chance of their progressing to later stages of cancer is eliminated.

Stage I - The polyp has progressed to a tumor and extends into the wall of the colon or rectum. Treatment can include resection surgery to remove the cancerous portion of the colon.Stage II - The cancer has spread beyond the colon or rectum to surrounding tissue but has not spread to lymph nodes. A resection surgery may also be used to treat this stage of cancer.

Stage II - The cancer has spread through the wall of the colon or rectum to surrounding tissue but has not spread to lymph nodes. Surgery is typically used to treat this stage of cancer.

Stage III - Cancer has spread outside the colon or rectum and to the lymph nodes in the surrounding area. In this stage, the cancer has not spread to other organs in the body, and treatment is more aggressive. Surgical resection, chemotherapy and other medical therapies may be necessary.

Stage IV - The cancer has spread to other organs in the body, such as the lungs or liver. Besides a surgical resection and chemotherapy, radiation treatment and surgery to remove other affected parts of the body may be necessary.

Recurrent Cancer - Cancer that comes back again after treatment, either in the colon, rectum or some other body part, is called recurrent. Even after successful treatment of colon or rectal cancer, regular checkups are necessary to find any recurrent cancer early.

Survival rates for colorectal cancer

The 5-year survival rate is the percentage of patients who are alive 5 years after their cancer is found. These numbers include people diagnosed with colorectal cancer who may have later died from other causes, such as heart disease. People with colon cancer tend to be older and may have other serious health conditions. This means the percentage of people surviving the colorectal cancer itself is likely to be higher, and many of them live much longer than 5 years.

The Registry for Inherited or Hereditary Colorectal Cancer