Colon Cancer

The American Cancer Society estimates that over 95,000 cases of colon cancer and 39,000 cases of rectal cancer will be diagnosed in the United States in 2016. Excluding skin cancers, colorectal cancer is the third most common cancer diagnosed in men and women and is the second leading cause of cancer-related deaths in the United States. In recent years, however, death rates have declined. This is likely do to the increased colonoscopy and polyp removal and as well as improved treatment methods.

What is colon cancer?

Colon cancer is cancer of the large intestine, the lower part of your digestive system. Most cases of colon cancer begin as small, noncancerous (benign) clumps of cells called adenomatous polyps. Overtime some of these polyps become cancerous.

Who is at risk for getting colon cancer?

Colon cancer can occur at any age, and no one is too young to develop colon cancer. However, about 90 percent of people with the disease are older than 50. Factors other than age that place you at a higher risk include:

  • Inflammatory intestinal conditions: Long-standing inflammatory diseases of the colon, such as ulcerative colitis and Crohn’s disease can increase your risk.
  • Family history: If there is a family history of colon cancer your risk is greater.
    Familial adenomatous polyposis is a rare hereditary disorder that causes you to develop hundreds of polyps in the lining of your colon and rectum. If these go untreated, you are likely to get colon cancer by age 40.
  • Diet: Colon cancer may be associated with a diet low in fiber and high in fat. Research is still occurring in this area.
  • A sedentary lifestyle: If you are inactive, you are more likely to develop colorectal cancer. This may be because when you’re inactive, waste stays in your colon longer.
  • Diabetes: People with diabetes have up to a 40 percent increased risk of developing colon cancer.
  • Smoking: More than one in 10 fatal colon cancers may be caused by smoking. Once diagnosed with colon cancer, smokers face a 30-40% increased risk of dying of the disease.
  • Alcohol: Heavy use of alcohol may increase your odds of colon cancer.
  • A personal history of colon cancer or polyps: If you’ve already had colon cancer or adenomatous polyps, you have a greater risk of colon cancer in the future.

What are the symptoms for colon cancer?

Common symptoms of colon cancer include:

  • Diarrhea or constipation
  • Rectal bleeding or blood in your stool
  • Narrow stools
  • Persistent abdominal discomfort, such as cramps, gas or pain
  • Abdominal pain with bowel movement
  • Change in bowl habits
  • Feeling that the bowel does not empty completely
  • Unexplained weight loss

These symptoms may be caused by many other problems, such as ulcers, an inflamed colon or hemorrhoids, it is important to consult your physician or a gastroenterologist.

What is the cause of colon cancer?

In the colon exaggerated growth of cells may cause precancerous polyps to form in the lining of the intestine. Over a long period of time some of these polyps may become cancerous. In later stages the cancerous polyps may penetrate the colon walls and spread to nearby lymph nodes and other organs. There are different types of colon polyps. Among the most common are:

  • Adenomas: These have the highest potential to become cancerous. These are commonly removed during screening tests such as flexible sigmoidoscopy or colonoscopy.
  • Hyperplastic polyps: These polyps are rarely a risk factor for colorectal cancer.
  • Inflammatory polyps: These polyps may follow after a bout of ulcerative colitis. Some inflammatory polyps may become cancerous.

How is colon cancer detected and diagnosed?

Most colon cancers develop from adenomatous polyps. Screening is very important for detecting polyps before they become cancerous. If colon cancer is found in its early stage there is a good chance for recover. Common screening and diagnostic procedure include the following:

  • Fecal occult blood test: This test checks a sample of stool for blood. Blood in the feces can be a result of other conditions. For this reason, many physicians prefer other screening methods in addition to fecal occult blood tests.
  • Flexible sigmoidoscopy: In this test the physician examines the rectum and sigmoid using flexible, slender and lighted tube.
  • Barium enema: The physician uses this test to evaluate the entire large intestine with the use of an x-ray and barium (a contrast dye).
  • Colonoscopy: This procedure is the most sensitive test for colon cancer, rectal cancer and polyps. This procedure is similar to sigmoidoscopy but the tube allows your physician to see your entire colon.
  • Biopsy: This procedure is the removal of tissue to check for the existence of cancer. The colon biopsy is the only method available to definitively diagnose colon cancer.
  • Genetic testing: If your family has a history of colon cancer, you may qualify for genetic testing.

After the cancer has been diagnosed your physician will stage your cancer. Staging will help determine what kind of treatment that you will need. The stages are:

  • Stage 0: This is the earliest stage. The cancer has not grown beyond the mucosa of the colon or rectum.
  • Stage I: The cancer has grown through the mucosa but not spread beyond the colon or rectum wall.
  • Stage II: The cancer has grown through the wall of the colon or rectum but has not spread to the nearby lymph nodes.
  • Stage III: The cancer has invaded nearby lymph nodes but isn’t affecting other parts of the body yet.
  • Stage IV: The cancer has spread to other organs.
  • Recurrent: The cancer has come back after treatment. It could recur in other parts of the body.

What are treatment options:

The type of treatment that your physician recommends is dependent largely on the stage of your cancer. Some of the treatment options that are available are:

  • Surgical Procedures: This procedure is where your surgeon removes the involved portion of the colon along with some of the normal tissue on either side to insure that none of the cancer is left behind. In some cases you may need total removal of the colon and rectum.
  • Chemotherapy: This procedure uses drugs to destroy cancer cells.
  • Radiation Therapy: This procedure uses x-rays to kill cancer cells. The goal of this therapy is to kill the cancer without harming the surrounding tissue.
  • Monoclonal Antibody Therapy: The FDA approved two drugs that treat colon cancer and rectal cancer by inhibiting the action of the cancer cell growth factor. The two drugs are bevacizumab (Avastin) and cetuximab (Erbitux)
  • Care Following Treatment: The follow up care after treatment is very important for colon cancer patients. During regular checkups you may have a physical exam to see if the cancer has spread to other locations.

Additional Resources

This report is intended for patient education and information only. It does not constitute advice, nor should it be taken to suggest or replace professional medical care from your physician. Your treatment options may vary, depending upon medical history and current condition. Only your physician and you can determine your best option.