Colorectal cancer

Colorectal cancer is a type of cancer that begins in the large intestine (colon) or the rectum (end of the colon). It is also known as colon cancer, rectal cancer, or bowel cancer. This type of cancer typically affects older adults, but it can happen at any age. It usually begins as small, noncancerous (benign) clumps of cells called polyps that form on the inside of the colon. Over time some of these polyps can become colorectal cancers.

Symptoms

Symptoms of colorectal cancer include changes in bowel habits, such as diarrhea or constipation or a change in the consistency of your stool, rectal bleeding or blood in your stool, persistent abdominal discomfort, such as cramps, gas or pain, a feeling that your bowel doesn't empty completely, weakness or fatigue and unexplained weight loss.

Causes

Colorectal cancer occurs when healthy cells in the colon or rectum develop errors (mutations) in their DNA. These cells continue to divide even when new cells aren't needed. As the cells accumulate, they form a tumor. With time, the cancer cells can grow to invade and destroy normal tissue nearby. And cancerous cells can travel to other parts of the body.

Risk Factors

Risk factors for colorectal cancer include older age, a personal history of colorectal polyps or colorectal cancer, inflammatory intestinal conditions, inherited syndromes that increase colon cancer risk, family history of colon cancer, low-fiber and high-fat diet, a sedentary lifestyle, diabetes, obesity, smoking, alcohol, radiation therapy for cancer.

Prevention

Prevention strategies for colorectal cancer include regular screening tests, a healthy diet, regular exercise, maintaining a healthy weight, and avoiding smoking and heavy alcohol use.

Treatment

Treatment for colorectal cancer often involves surgery to remove the cancer. Other treatments, such as radiation therapy and chemotherapy, might also be recommended.