Colon Cancer Risk Factors

No one knows the exact causes of colon cancer. Doctors often cannot explain why one person develops this disease and another does not. However, it is clear that colon cancer is not contagious. No one can catch this disease from another person.

Research has shown that people with certain risk factors are more likely than others to develop colon cancer. A risk factor is something that may increase the chance of developing a disease.

Studies have found the following risk factors for colon cancer:

Age over 50: colon cancer is more likely to occur as people get older. More than 90 percent of people with this disease are diagnosed after age 50. The average age at diagnosis is 72.

Colorectal Cancer Overview

Colorectal cancer, or colon cancer, occurs in the colon or rectum. As the graphic below shows, the colon is the large intestine or large bowel. The rectum is the passageway that connects the colon to the anus.

Colon cancer, when discovered early, is highly treatable. Even if it spreads into nearby lymph nodes, surgical treatment followed by chemotherapy is highly successful. In the most difficult cases — when the cancer has metastasized to the liver, lungs or other sites — treatment can prolong and add to one’s quality of life.

Most colon cancers develop first as colorectal polyps, which are abnormal growths inside the colon or rectum that may later become cancerous.

Colon Cancer Statistics 2013

Colon cancer is the third most commonly diagnosed cancer and the second leading cause of cancer deat

h in men and women combined in the US. The American Cancer Society estimates that 142,820 people will be diagnosed in 2013 and that 50,830 will die from colon cancer in the United States.

On average, the lifetime risk of developing colon cancer is about one in 20 (5%), however, this varies widely according to individual risk factors.

About 72% of cases arise in the colon and about 28% in the rectum.

Early Detection

With regular screening, colon cancer can be found early, when treatment is most effective. In many cases, screening can prevent colon cancer by finding and removing polyps before they become cancer. And if cancer is present, earlier detection means a chance at a longer life -- generally, five-year survival rates for colon cancer are lower the further advanced the disease is at detection:

Colonoscopy (“The Gold Standard”)

TESTS THAT DETECT CANCER & POLYS

Colonoscopy (“The Gold Standard”)

What happens: The inside of the rectum and entire colon are examined using a long, lighted tube called a colonoscope. 

Flexible Sigmoidoscopy

What happens: Examines your rectum and lower part of the colon with a lighted tube called a sigmoidoscope.

When to get screened (if not high risk): Every five years starting at age 50.

Virtual Colonoscopy

What happens: Uses x-rays and computers to take 2- or 3-dimensional images of your colon and rectum.

When to get screened (if not high risk): Every five years starting at age 50 (though timing has not been closely studied).

Double-Contrast Barium Enema (DCBE)

What happens: Air and barium are pumped into your rectum. The solution will show polyps or tumors on x-rays.

When to get screened (if not high risk): Every five to ten years starting at age 50.

TESTS THAT INDICATE CANCER