Le cancer du colon (cancer colorectal)
As the name suggests, the colorectal cancer is formed in the colon or in the rectum, the last part of the large intestine.
Le colorectal cancer arrives at 3e rank of the most common cancers in Canada, in both men and women. One in 14 men and 1 in 15 women are at risk of developing colorectal cancer in their lifetime1.
Colorectal cancer is much more common in industrialized countries. Lifestyle habits, mainlyfood, moreover play a primordial role in its appearance. This explains, for example, that the Japanese, little affected by colorectal cancer in Japan, become so just as much as their fellow Americans a few years after having emigrated to the United States and adopted their diet.
Some people can get it because of hereditary predisposition. But in 75% of cases, heredity is not involved.
Evolution
Le colorectal cancer takes several years to form, like most cancers. It usually does this from polyps in the wall lining the inside of the colon. Polyps are small, fleshy growths. There are several kinds. Most often, they are benign. However, it is known that some of them can become cancerous. It takes an average of 10 years for a polyp to form a cancerous tumor. Polyps (cancerous or not) sometimes cause digestive discomfort. For more information, see our Intestinal Polyps fact sheet.
As soon as the doctor detects polyps in a patient, he performs tests to see if they pose a risk to his health.
At an advanced stage, colorectal cancer can spread to ganglia lymphatics, then to the liver and then to other parts of the body forming metastases.
In Canada, colorectal cancer is the 2e cause of death by cancer. The death rate 5 years after diagnosis is about 40%, in both sexes.
Currently, more than half of cases are diagnosed in people aged 70 and over1. Healthcare professionals would like more people to get tested for screening regularly, from the age of 50, and earlier in people at risk. The earlier cancer is detected, and it is possible to do so before symptoms arrive, the better the chances of healing.
When to consult
If you have a blood in the stool or diarrhea or Constipation that persists, it is important to see a doctor. For those at risk, it is advisable to undergo a screening test. Discuss this with your doctor.