Bowel cancer--otherwise known as colorectal cancer, according to Professor Jonathan Rhodes, consultant gastroenterologist of Netdoctor--is a cancer of the colon or rectum. It's the second-most common cause of deaths related to cancer, but 40 percent to 50 percent of all cases are curable.The cause in most cases is not known, yet many risk factors are.
Personal History
Personal history pertains to those who either have a history of polyps--a group of non-cancerous cells that become cancerous over time--or a history of bowel cancer itself. The risk increases in people whose polyps are large or excessive in number.
People with a prior history of bowel cancer are more likely to develop new cancers in different areas of the colon or rectum, especially if they were younger than 50 when receiving their first diagnosis, the American Cancer Society says.
Age
Tgough bowel cancer can develop in younger adults, the risk increases in those older than 50. The Mayo Clinic says that approximately 90 percent of people who get a diagnosis of this cancer are older than 50.
Intestinal Conditions
A history of inflammatory bowel disease, which includes diseases such as ulcerative colitis and Crohn's disease, causes an inflammation of the colon for a long period. The American Cancer Society says this eventually results in a condition known as dysplasia. Dysplasia causes the cells in the lining of the colon or rectum to appear abnormal; over time, these cells become cancerous.
Family History
Although most cases of bowel cancer occur in people with no family history, approximately one in five cases develops in those whose family members also have this disease. The risk increases in people who have a personal history of polyps or bowel cancer and one or more first-line relatives--such as a parent or sibling--with this disease.
Genes
Familial adenomatous polyposis is a result of changes in the APC gene that a person inherits from her parents. The American Cancer Society says fewer than 1 percent of all bowel cancers are a result of this factor.
