Colorectal cancer, also known as colon cancer, is cancer that occurs in either the large intestine or rectum. The colon is also known as the large intestine or bowel. The rectum is several inches long and is located between the sigmoid colon, the last part of the colon, and the anus. Most cases of colorectal cancer begin as small, benign clusters of cells known as polyps. Over time some of these polyps may become cancerous.
According to the Centers for Disease Control and Prevention, or CDC, colorectal cancer is the second-leading cause of death in the United States. Colorectal cancer is also the third most-common cancer for men and women combined.
Causes of Colorectal Cancer
Cancer occurs when healthy cells become altered. They grow and divide in a way that keeps the body from functioning normally. In the colon and rectum, precancerous cells may form in the lining of the intestine, which may become cancerous over a period of time. Precancerous growths usually occur as adenomatous polyps - clusters of abnormal cells in the glands covering the inner wall of the colon.
Risk Factors for Colorectal Cancer
The exact cause of colorectal cancer is unknown, but there are several risk factors for the disease, including:
- Inflammatory bowel disease
- A family history of colorectal cancer or polyps
- Genetic predisposition
- History of cancer
- A lack of exercise
- Diet and lifestyle choices
- Alcohol use
- A diet lacking in fruit and vegetables
Symptoms of Colorectal Cancer
Many people with colorectal cancer experience no symptoms in the early stages. Common warning signs may include the following:
- Changes in bowel movements, including constipation or diarrhea
- Rectal bleeding or blood in the stool
- Abdominal discomfort or bloating
- Weakness or fatigue
- Unexplained weight loss
- Stools that are narrower than usual
- Nausea or vomiting
Treatment of Colorectal Cancer
The type of treatment recommended will depend on the staging of the cancer and the location of the tumor. The main treatment options for colorectal cancer are surgery, chemotherapy, biological therapy and radiation therapy. These treatments may be used alone or in combination with each other.
In colorectal cancer surgery, the cancerous part of the colon or rectum is removed, along with some normal tissue on each side to ensure no cancer is left behind. Surgery may be performed either laparoscopically, as open surgery or as a colonoscopy. The surgeon will usually be able to reconnect the healthy portions of the colon or rectum. When a reconnection is not possible, a permanent or temporary colostomy will be performed. This involves creating an opening in the wall of the abdomen for the elimination of body waste.
Chemotherapy uses drugs to destroy cancer cells. It can be used to destroy cancer cells after surgery, to control tumor growth, or to relieve the symptoms of colorectal cancer. Chemotherapy may be recommended if the cancer has spread beyond the wall of the colon or rectum. Chemotherapy drugs may be administered orally or through a vein.
Biological therapy uses monocional antibodies to bind to cancer cells. They control the growth of cancer cells and the spread of the cancer. Biological therapy may be combined with chemotherapy and administered at the same time.
Radiation therapy uses high-energy X-rays to kill cancer cells that might remain after surgery, to shrink large tumors before an operation so they can be removed more easily, or to relieve symptoms of colorectal cancer. Radiation damages the genetic material of cells in the area being treated, preventing them from growing. Although radiation may damage normal cells as well, the normal cells can usually repair themselves while the cancer cells cannot.
Prevention of Colorectal Cancer
Diet and Exercise
An initial step toward the prevention of colorectal cancer includes combining a daily exercise program with a healthy lifestyle that includes weight control. Eating a diet rich in fruits, vegetables, and whole grains containing vitamins, minerals, fiber, and antioxidants may play a role in prevention of cancer. Reducing or eliminating alcohol consumption and smoking may also help in colorectal cancer prevention.
Some medications have been found to reduce the risk of precancerous polyps or colorectal cancer. It has been proposed that a daily dose of aspirin, with the physician's approval, may prevent cancer cells from multiplying.
Most health problems respond best to treatment when they are detected and treated as soon as possible. Regular checkups can catch abnormalities or problems early. Screening for colorectal cancer may include a rectal exam, fecal occult blood test, a sigmoidoscopy, barium enema, and a colonoscopy. A screening may find precancerous polyps before they become cancerous. An initial screening colonoscopy is recommended for everyone at age 50. For African-Americans, an initial screening colonoscopy is recommended at age 45. If there is a family history of colorectal cancer or polyps, colorectal screening may need to begin at an earlier age.
To learn more about our Colon/Rectum Cancer Services, please contact us at (516) 627-5262 today to schedule an appointment.