There are no specific known cause of most of the colorectal cancers. There are certain factors that may be considered as risk factors. Risk factors increase susceptibility of a person to a specific type of cancer. Bowel cancer risk factors can be studied as modifiable and those that cannot be changed.

Some of the factors that cannot be changed are:

• Age: The risk of colorectal cancer increases with age. People above the age of 50 are considered more susceptible to bowel cancer. It cannot be said that younger people cannot be diagnosed with this type of cancer.
• Personal History: History of polyps may increase the risk of

  

  colorectal cancer. Polyps are growths of non-cancerous nature that may be found in the colon or the rectum. These are common in people who are over the age of 50. Adenoma, a type of polyp are known to increase the risk of colorectal cancer. Women who have dealt with breast, ovarian or uterine cancer can have a higher risk of this type of cancer. People who have been treated for colorectal cancer earlier before the age of 60 may have a recurrent medical condition.

• Family History: People whose siblings, parents and children who have been diagnosed with colorectal cancer should be well aware of their high chances and should opt for regular screening.
• Race: People of African-American descent are known to have a higher incidence of colorectal cancer. It is lowest in case of people of Asian-American descent, Hispanics and American Indians.
• Diabetes: People with type 2 diabetes are at 30-40% increased risk for this type of cancer.