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Excluding skin cancers, colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that about 106,370 new cases of colon cancer (50,400 men and 55,970 women) and 40,570 new cases of rectal cancer (23,220 men and 17,350 women) will be diagnosed in 2004.
Colorectal cancer is expected to cause about 56,730 deaths (28,320 men and 28,410 women) during 2004, accounting for about 10% of cancer deaths.
The death rate from colorectal cancer has been dropping for the past 15 years. There are probably a number of reasons for this. One reason is probably because polyps are found by screening before they can develop into cancers.. Also, colorectal cancers are being found earlier when they are easier to cure, and treatments have improved.
The 5-year relative survival rate is 90% for people whose colorectal cancer is treated in an early stage, before it has spread. But, only 38% of colorectal cancers are found at that early stage. Once the cancer has spread to nearby organs or lymph nodes, the 5-year relative survival rate goes down to 66%. For people whose colorectal cancer has spread to distant parts of the body such as the liver or lungs, the 5-year relative survival rate is 9%.
The 5-year survival rate refers to the percentage of patients who live at least 5 years after their cancer is diagnosed. Many of these patients live much longer than 5 years after diagnosis. The 5-year rate is used to produce a standard way of discussing prognosis. Five-year relative survival rates don't include patients dying of other diseases. Five-year relative survival rates are considered to be a more accurate way to describe the prognosis for patients with a particular type and stage of cancer. Of course, 5-year rates are based on patients diagnosed and initially treated more than 5 years ago. They may no longer be accurate. Improvements in treatment may result in a better outlook for recently diagnosed patients. | 
