According to the CDC, of cancers affecting both men and women, colorectal cancer (cancer of the colon and rectum) is the second leading cancer killer in the United States. In the United States in 2008, 142,950 people were diagnosed with colorectal cancer, and 52,857 people died from it.
Don't keep trying to find an excuse to put it off any longer. If you're 50 years of age or older, you should be screened for colorectal cancer.
Source: CDC: Colorectal (colon) Cancer