Colorectal Cancer


Cancer of the colon or rectum is often called colorectal cancer. The colon and the rectum are part of the large intestine, which is part of the gastrointestinal tract. Colon and rectum cancers develop slowly over a period of several years. Most of these cancers begin as a polyp, which is a growth of tissue, in the center of the colon or rectum. Over the past several years, the number of new cases of colorectal cancer in the U.S. has been decreasing slightly and the number of deaths has decreased as well. It is important to quickly and effectively evaluate the extent of the colorectal cancer. In order to diagnose this condition, an endoscopic examination is frequently performed to visualize any abnormality in the lining of the colon. A biopsy is taken of the lining of the colon during the colonoscopy, and the tissue is sent to the pathology laboratory. The surgical pathologist at the laboratory determines whether an abnormality exists by microscopic examination of the colon tissue sample (biopsy), and whether it is benign or malignant. The treatment and the outlook for your recovery depend on the stage of the cancer. Your healthcare provider will recommend any additional testing that he/she feels are needed to evaluate the cancer prior to treatment.

Background Information

Colorectal cancer is the second leading cause of cancer deaths in the U.S. The risk of colorectal cancer tends to increase after the age of 50.

A screening test, such as a colonoscopy, can find colorectal cancers at an early stage and greatly improve the chances of successful treatment. Screening tests can also help prevent some cancers by allowing doctors to find and remove polyps that might become cancerous.

Individuals who are symptomatic may experience a change in bowel habits such as diarrhea or constipation, blood in the stool, abdominal cramping or pain and tiredness.

Risk Factors:
Although the cause of colorectal cancer is unknown, it can sometimes be associated with known risk factors. Many risk factors are able to be changed, though not all can be eliminated. Lack of exercise, diets high in fat and calories and low in fiber, smoking and alcohol abuse and obesity have all been linked to colorectal cancer. Maintaining a healthy lifestyle may help reduce your risk of developing colorectal cancer. Conditions such as ulcerative colitis, an inflammatory disease of the colon, and polyps can increase an individualís risk as well. Screening for colorectal cancer is recommended at an earlier age for these individuals and polyps which are found should be removed. Individuals who have a family history of colorectal cancer or have had colorectal cancer themselves are at a higher risk for developing it. These individuals should likely be screened earlier and more frequently.

Follow-up and Treatment Options

The treatment or therapy depends on the stage of the cancer, whether it has blocked or created a hole in the colon, the blood levels of carcinoembryonic antigen, whether the cancer has recurred and your general health. Below is a listing of potential treatment options for colorectal cancer. The main treatments for colorectal cancer are surgery, chemotherapy, and radiation therapy. Only a physician can determine the most appropriate treatment.

The surgical removal of the cancer is the most common form of treatment for all stages of colorectal cancer. The surgeon will likely remove the cancerous tissue as well as a smaller section of healthy tissue surrounding it and sew the two ends of the colon back together. Often times the lymph nodes around the cancerous area will also be removed to determine if the cancer has spread. Sometimes chemotherapy or radiation therapy are used after surgery to kill any cancer cells that are left.

Chemotherapy is the use of drugs to kill the cancer cells or stop them from dividing. Most chemotherapy is given in the form of injections, however some can be taken by mouth. These drugs enter the bloodstream and travel throughout the entire body. The use of chemotherapy after surgery can increase the survival rate for patients with some stages of colorectal cancer. Chemotherapy can also help relieve symptoms of advanced cancer.

Radiation Therapy:
Radiation therapy involves the use of high-energy rays to kill cancer cells. Radiation therapy is focused directly on the affected area and is sometimes given after surgery to kill any remaining cancer cells. If the cancer has attached to an internal organ or the lining of the abdomen, radiation therapy may be used to kill the cancer cells that are left behind after surgery. For rectal cancer, radiation is also given to prevent the cancer from coming back in the surgical site and to treat local recurrences that are causing symptoms such as pain.

Questions to Ask Your Healthcare Provider
  • Are there any other tests that we need to perform?
  • Where is my cancer located and has it spread?
  • What treatment do you suggest?
  • What are the benefits of this type of treatment?
  • What are the risks and side effects of this treatment option?
  • Is there anything I should be doing or not doing during treatment?
  • What are the steps after treatment?
  • What are the chances of recurrence after my treatment plan?
Sources for Additional Information

The content of this web page and corresponding downloadable handout is provided to you as general information and not intended as a diagnosis. Please consult with your personal physician regarding the essential details about your condition. Updated 12/2013.

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