Colorectal Cancer Risk Factors
No one can yet pinpoint the causes of colorectal cancers. Doctors and researchers are unable to explain why one person develops the disease while another does not. However, research has shown that people with certain risk factors may increase the chance of developing some form of colorectal cancer. You may want to talk to your doctor about ways to try to reduce your risk of colorectal cancer, and understanding your family history of cancer.
Your doctor's office is one of the best places to keep a regular schedule of annual check-ups and screenings. To select an Alta Bates Summit physician, you can use our Find A Doctor search tool.
Age
Colorectal cancer is most likely to occur as people age. Over 90% of those with some form of this disease are diagnosed after the age of 50. According to the National Cancer Institute the average age at diagnosis is 72. Even though statistics show that age is a significant factor in the risk of colorectal cancer, there are those in their 20s, 30s, and 40s who do contract the disease.
Family History
Close relatives (parents, brothers, sisters, or children) of a person who had colorectal cancer or colon polyps are potentially more likely to develop this type of cancer, especially if the family member developed the cancer at an early age and may have a genetic cancer syndrome with a family history of certain types of cancer. If many family members have had colorectal cancer, the chances may increase even more.
If a family member had cancer at an early age, it is important to talk to your doctor about when to start screening with a colonoscopy.
Colorectal Polyps
Polyps are abnormal growths on the inner wall of the colon or rectum. They are relatively common in people over age 50. Most polyps are benign (noncancerous), but researchers believe the majority of colorectal cancers develop in polyps known as adenomas.
Ulcerative Colitis or Crohn’s Disease
An individual who has had or suffers from a condition causing inflammation of the colon (such as ulcerative colitis or Crohn’s disease) is at an increased risk of developing colorectal cancer.
Alcohol Use
Many studies have found there is an association between alcohol intake and colon cancer. According to the ACS, the risk increases with the amount of alcohol consumed and is highest among heavy alcohol users.
Tobacco Use
People who smoke are more likely than non-smokers to develop the following cancers: acute myeloid leukemia (cancer of the blood), bladder, breast, cervix, esophagus, kidney, larynx (voice box), lung, mouth, pancreas, stomach, and throat.
The risk of cancer for people who quit is lower than the risk for people who continue to use tobacco. (But the risk of cancer is lowest among those who've never used tobacco.)
For people who have already developed cancer, quitting may reduce the chance of getting another cancer, or the recurrence of cancer.
Diet & Exercise
Diet and exercise are important factors in the overall decrease of risk in cancers. It suggested by the American Cancer Society that high dietary fat and low fiber may be a contributing factor for colorectal cancer. The numbers show that the disease is significantly more common in countries where red meat and dairy products are dietary staples, compared to countries where the basic diet consists of rice, soybean products, and vegetables.
Lack of physical activity and being overweight are risk factors for breast, prostate, colon, esophageal, kidney, and uterine cancers.
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For more information on reducing risks for colorectal cancer, please call the Markstein Cancer Education and Prevention Services at (510) 869-8833 or visit the American Cancer Society's Learn About Colorectal Cancer website .
