Colon cancer forms in the tissues of the colon (the longest part of the large intestine). Most colon cancers are adenocarcinomas (cancers that begin in cells that make and release mucus and other fluids).

Rectal cancer forms in the tissues of the rectum (the last several inches of the large intestine closest to the anus).

Estimated new cases and deaths from colon and rectal cancer in the United States in 2009:

New cases:  106,100 (colon); 40,870 (rectal)
Deaths:  49,920 (colon and rectal combined)
 
To learn more about colon and rectal cancer, visit the National Cancer Institute web site at: http://www.cancer.gov/cancertopics/types/colon-and-rectal