The risk of developing colon or rectal cancer increases with age. Even though teenagers and adults may also experience colon cancer, more than 90% of colon cancer cases occur in people over the age of 50, usually at around 72 years old. Smokers are more likely to develop colon cancer than non-smokers, and men have higher cancer rates than women. In the United States, black people have higher rates of colorectal cancer.
The causes of colon cancer are diverse, but sometimes, colon cancer can be caused by adenomatous polyps. People who have adenomas are at higher risk of developing additional polyps that lead to colon and rectal cancer. Asbestos exposures generate polyp mutations that occur when asbestos fibers become lodged in the tissues of the colon. Thus, benign polyps mutate and become malignant. In time, malignant polyps turn into the colon and even rectal cancer.