Colorectal cancer, also known as bowel cancer, colon cancer, or rectal cancer, is any cancer that affects the colon and the rectum.

The American Cancer Society estimate that about 1 in 21 men and 1 in 23 women in the United States will develop colorectal cancer during their lifetime.

It is the second leading cause of cancer death in women, and the third for men. However, due to advances in screening techniques and improvements in treatments, the death rate from colorectal cancer has been falling.

Colorectal cancer may be benign, or non-cancerous, or malignant. A malignant cancer can spread to other parts of the body and damage them.

Symptoms

Symptoms of colorectal cancer include:

• changes in bowel habits
• diarrhea or constipation
• a feeling that the bowel does not empty properly after a bowel movement
• blood in feces that makes stools look black
• bright red blood coming from the rectum
• pain and bloating in the abdomen
• a feeling of fullness in the abdomen, even after not eating for a while.
• fatigue or tiredness
• unexplained weight loss
• a lump in the abdomen or the back passage felt by your doctor
• unexplained iron deficiency in men, or in women after menopause

Most of these symptoms may also indicate other possible conditions. It is important to see a doctor if symptoms persist for 4 weeks or more.

Prevention

A number of lifestyle measures may reduce the risk of developing colorectal cancer:

• Regular screenings: Those who have had colorectal cancer before, who are over 50 years of age, who have a family history of this type of cancer, or have Crohn's disease should have regular screenings.
• Nutrition: Follow a diet with plenty of fiber, fruit, vegetables, and good quality carbohydratesand a minimum of red and processed meats. Switch from saturated fats to good quality fats, such as avocado, olive oil, fish oils, and nuts.
• Exercise: Moderate, regular exercise has been shown to have a significant impact on lowering a person's risk of developing colorectal cancer.
• Bodyweight: Being overweight or obese raises the risk of many cancers, including colorectal cancer.

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