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Colorectal cancer

Colorectal cancer (cancers of the colon and rectum combined) is the second leading cause of cancer death in the United States, according to the American Cancer Society (ACS).

But researchers suggest that 90 percent of all colorectal cancer cases and deaths can be avoided. That’s because with regular screening, most cases can be treated before they become cancerous.

Colorectal cancer usually begins forming as polyps, or tissue growths, in the colon or rectum (both part of the large intestine). If your doctor finds polyps during a screening, he or she will most likely remove them immediately. If the polyp is large, your doctor may perform a biopsy.

Exam time

Getting regular checkups may be the best way to prevent colorectal cancer. Early detection of any abnormal cells allows for prompt treatment and makes curing colorectal cancer more likely.

If you are in good health and have no known risk factors, the ACS recommends that you be screened for colorectal cancer beginning at age 50. (Those with risk factors for developing colorectal cancer should be screened earlier and more often.) Your doctor will help you decide which of the following screening guidelines based on ACS recommendations is best for you:

  • A fecal occult blood test or fecal immunochemical test once a year. These are simple at-home tests that check for blood in the stool. Special cards are coated with a stool sample and returned to the physician or lab.
  • A stool DNA test as recommended by your doctor. This test looks for evidence of cancer cells shed from the colon into the stool.
  • A flexible sigmoidoscopy once every five years. This is an outpatient procedure for examining the lower part of the large intestine. A doctor uses a thin, flexible tube with a light and a tiny camera attached to look for polyps, tumors or abnormal areas.
  • A barium enema once every five years. During this procedure a liquid containing barium is inserted into the rectum and colon. Barium, a silver-white metallic compound, helps to show the image of the lower gastrointestinal tract on an X-ray.
  • A colonoscopy once every 10 years. This examination involves viewing the inside of the colon and rectum using a thin, lighted tube. If your doctor sees polyps or other abnormal tissue during the procedure, he or she can remove the growth for examination under a microscope.
  • A CT colonography (virtual colonoscopy) once every five years. This test uses advanced computed tomography (CT) imaging to create a three-dimensional view of the colon and rectum.

Treatment choices

If you are diagnosed with colorectal cancer, your treatment will depend mainly on the size, location and extent of the tumor and your general health. Several different types of treatment are used, and sometimes different methods are combined.

  • Surgery to remove the tumor is the most common treatment. Generally, the surgeon removes the tumor along with part of the healthy colon or rectum and nearby lymph nodes. In most cases, the doctor can reconnect the healthy parts of the colon or rectum.
  • A colostomy may be needed if the surgeon can’t reconnect the healthy portions of the colon. A colostomy is a surgical opening that provides a new path for waste to leave the body. After the procedure, the patient wears a special bag to collect body waste. Most patients need a temporary colostomy to let the lower colon or rectum heal after surgery; however, some patients will need the colostomy for the rest of their lives.
  • Chemotherapy, the use of anticancer drugs to kill cancer cells, is another standard treatment. Chemotherapy may be given to destroy any cancerous cells that remain in the body after surgery, to control tumor growth or to relieve symptoms of the disease. Most anticancer drugs are given intravenously; some are given in pill form.
  • Radiation therapy, also called radiotherapy, uses X-rays to kill cancer cells. Radiation therapy is most often used for patients whose cancer is in the rectum. Doctors may use radiation therapy before surgery to shrink a tumor so it’s easier to remove or after surgery to destroy any remaining cancer cells.
  • Biological therapies, also called immunotherapies, are used to repair, stimulate or enhance the immune system’s natural cancer-fighting abilities. The therapies, usually administered by injection, may be given after surgery either alone or combined with chemotherapy or radiation treatment.

Colorectal cancer risk factors

You may have an increased chance of developing colorectal cancer if you:

  • are over age 50
  • have had certain types of polyps
  • have a close family member who had colon cancer diagnosed before age 60
  • have had colorectal cancer that was completely removed
  • have long-standing chronic ulcerative colitis or Crohn’s colitis
  • are physically inactive
  • eat a high-fat, high-calorie diet
  • are overweight
  • smoke or drink alcohol heavily
  • are Jewish and of Eastern European descent (Ashkenazi Jewish)