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Colorectal Cancer Awareness

Benign tumors are not cancer. They do not grow into nearby tissue or spread to other parts of the body. Benign tumors can be removed and usually are not life threatening. In some instances, benign tumors can turn into cancer.

Malignant tumors are cancer. These cells can creep into nearby tissue and damage other organs. Sometimes cells from the tumor may break off and travel through the bloodstream or the lymph system and start tumors in other parts of the body.

What is Colorectal Cancer?
The colon and rectum form a long, muscular tube called the large intestine or large bowel. The colon is the upper 5 to 6 feet of the large bowel and the rectum is the last 6 to 8 inches. The large bowel, along with the esophagus, stomach, and the small bowel, is part of the body's digestive system. The digestive system absorbs minerals, proteins, and vitamins from the food you eat and stores the waste until it passes out of the body.

Tumors can begin anywhere in the colon or rectum. Sometimes a benign growth, called a polyp, may start to grow on the wall of the colon or rectum. Polyps in the colon or rectum should be removed because they can become cancerous. These can be easily removed in a doctor's office during an examination using a lighted flexible tube. If not removed, these cancer cells can spread outside of the colon or rectum to the nearby lymph nodes or blood stream. These cells can also spread to other parts of the body such as the liver and lungs. People who have had one polyp are more likely to develop others, so it is very important they have regular check-ups to prevent the start of cancer.

Colorectal cancer is the third most common cancer in both men and women. In 2006, there will be an estimated 148,610 new cases of colorectal cancer and about 55,170 people will die from the disease. Like most health problems, colorectal cancer responds best to treatment when it is diagnosed and treated as early as possible, especially before it has a chance to spread outside of the colon.

Risk Factors
Studies have found that certain things may increase a person's risk of getting colorectal cancer. These include being over 50 years of age; having a history of polyps in the colon, ulcerative colitis, or Crohn's disease, and having a family history of colon cancer or familial polyposis syndrome. Studies have shown diet, especially a diet high in fat and low in fiber, may also contribute to the development of colon cancer. Other risk factors include daily drinking of alcoholic beverages, obesity, smoking, and an inactive way of life.

Prevention Tips
There are steps you can take to help prevent colorectal cancer.

• Eat a diet high in fiber and/or fruits and vegetables, calcium, FDA approved quantities of vitamins D and E.
• Increase your activity level. Research has linked an inactive lifestyle with an increased risk of colon and rectal cancer. A person is considered physically active if they exercise for at least 30 minutes a day.
• Limit your alcohol intake. People who drink more than one alcoholic beverage a day tend to develop colorectal cancer more often than those who do not drink alcohol.
• Have regular screening examinations. Screening exams can find and remove precancerous polyps before they turn into cancer. Follow your doctor's advice about having tests for colon cancer.
• Nonsteroidal Anti-Inflammatory Drugs. Some studies have shown that using nonsteroidal anti-inflammatory drugs (NSAIDS) may decrease the risk of colon and rectal cancer. Any drug may have side effects. Talk with your doctor about the pros and cons of these drugs.
• Statin Use. There is no evidence that statin use affects the risk of colorectal cancer.

Screening Tests
You can take an active role in the prevention and early detection of colon and rectal cancer by getting tested regularly after the age of 50. Talk to your doctor about which test you should have.

There are five tests commonly used to screen for colorectal cancer:

Digital Rectal Exam— A doctor inserts a gloved and lubricated finger into the rectum. It is used as the first method of detection for rectal cancer.

Guiac Test/Hemoccult— A test to see if there is hidden blood in the stool. A positive result may be a sign of cancer.

Sigmoidoscopy— An examination of the rectum and lower colon with a hollow lighted tube. It is used to find polyps and cancer, to find the cause of bleeding. Tissue can be removed for a doctor to look at under a microscope to make a diagnosis. Requires laxatives to clean the bowel.

Colonoscopy— A tube that looks in the rectum and entire colon by using a long fiber optic telescope that is lighted and flexible. It may reveal polyps, cancer, colitis, and diverticulosis. Tissue can be removed for a doctor to look at under a microscope to make a diagnosis. May require sedation. Requires laxatives to clean the bowel.

Barium enema— X-ray of the entire lower bowel using barium solution that is given through the rectum. This test can find polyps, cancer, colitis, and diverticulosis. Laxative and regular enemas are used to clean the bowel.

There are two new screening tests being studied in clinical trials. Virtual colonoscopy is a procedure that uses x-rays called computed tomography or CT. Clinical trials are comparing virtual colonoscopy with the commonly used colorectal cancer screening tests.

DNA stool test is the other test being studied. This test checks DNA in stool cells for genetic changes that may be a sign of colorectal cancer.

Symptoms to Watch For
Colorectal cancer can cause a wide range of symptoms. Warning signs to watch for include:

• A change in usual bowel habits, (constipation, diarrhea or both)
• Stools that are more narrow than usual
• Blood in or on the bowel movement (stool), or in the toilet after having a bowel movement
• Lower abdominal discomfort, such as bloating, fullness and/or cramps
• Frequent painful or cramping gas pains
• A feeling that the bowel does not empty completely
• Weight loss with no known reason
• Unusual tiredness

These same symptoms may be caused by problems other than cancer. Only your doctor can determine the cause. If you have any of these symptoms you should see your doctor.