Colorectal Cancer Chapter 1

Colorectal Cancer Screening (VIDEO)

Colorectal cancer is one of the few preventable forms of cancer thanks to effective screening. For many people, screening for colorectal cancer is an unpleasant thought, but knowing your options and taking a pro-active approach especially if you're over 50 can save your life. In this video, you can learn the "ins and outs" of colonoscopy, as well as learn about a new technique called virtual colonoscopy, which uses high-tech CT scans to screen the colon.

Special thanks: Washington Radiology Associates, Metro Gastroenterology

Colorectal Cancer

Colorectal cancer refers to cancer of the colon and cancer of the rectum. The colon is the longest part of the large intestine, and the rectum is the last several inches of the large intestine, closest to the anus. Read more

Colon Anatomy & Function

The Digestive System
The digestive system is like a long tube that runs from the mouth to the anus and includes organs that help the body digest and absorb food and nutrients. The organs that make up the digestive system include the mouth, esophagus, stomach, small intestine, large intestine (or colon), rectum, and anus. Inside these organs is a lining called the mucosa. The digestive tract also contains a layer of smooth muscle. The muscle moves food through the tract in a wavelike movement called peristalsis, helping to mix it and break it down. Read more

What Is Colorectal Cancer?

The process of cell growth in the body is normally an orderly one. Cells grow and divide as necessary to produce more cells as they are needed. Cells that are old or damaged die, and are replaced with new cells. Read more

Tumor Growth

Two types of growth occur in the colon:

  • Noncancerous growths, such as polyps
  • Malignant or cancerous growths, which usually begin as polyps


Colorectal cancer can occur without polyps, but this is rare and accounts for less than 1% of all colorectal cancers diagnosed in the US each year. It usually happens in individuals with long-standing inflammatory bowel diseases, such as chronic ulcerative colitis and Crohn's colitis.Read more

Cancer Staging

After colon cancer has been diagnosed, the next step is to perform tests to determine if the cancer has spread within the intestine or to distant parts of the body. This is called staging. Staging helps the doctor to decide the most appropriate treatment for the cancer at its current stage. Read more

Signs & Symptoms

Unfortunately, colorectal cancer is often asymptomatic (without symptoms) in its early stages Symptoms may appear only when the cancer has reached an advanced stage and the cancer is more difficult to treat. When symptoms do appear, they vary according to the size of the cancer and its location in the colon or rectum. Read more

Screening & Diagnosis

Screening for colorectal cancer can mean the difference between catching the disease in its early stages and catching it in its advanced stages, and this literally can be the difference between life and death. Precancerous polyps can be easily removed, and if colorectal cancer is caught early, it often is treatable and the chances of a full recovery are good. But cancerous polyps that have invaded the intestinal wall or even metastasized can prove fatal. Read more

A Less Invasive Look

Virtual colonoscopy is a new technology that uses computed tomography (CT), or, less often, magnetic resonance imaging (MRI) images to look for polyps, cancer, or other diseases of the colon when an abnormality is suspected. A computer program assembles the images to create an animated, three-dimensional view of the interior of the colon. The preparation for the procedure is similar to that for a colonoscopy, but the procedure itself takes only about 10 minutes, and no sedation is required. If abnormalities are found, a conventional colonoscopy will need to be performed for removal or biopsy of the growth. Read more

Treating Colorectal Cancer

There are three main treatment options for colorectal cancer:

  • Surgery removes cancer cells
  • Chemotherapy kills cancer cells
  • Radiation therapy destroys cancerous tissue

The choice of treatment depends in part on the stage of the cancer.

Surgery (colectomy) is the main treatment for colorectal cancer. Stage 0 colon cancer may be treated by removing the cancer cells, often during a colonoscopy. In stages I, II, and III cancer, the affected part of the colon is removed surgically. The surgeon may perform a resection, consisting of a partial colectomy (removing the cancer and a small amount of healthy tissue around it) and an anastomosis (sewing the parts of the colon back together). Nearby lymph nodes may also be removed and biopsied. Read more

Detecting Cancer Recurrence

Recurrent Cancer
Colorectal cancer that is caught in its early stages may never come back, or it may recur. If the cancer doesn't recur within 5 years, it's considered cured. Stage I, II, and III cancers are considered potentially curable. In most cases, stage IV cancer is not curable. Read more

Preventing Cancer

Risk Factors
No one knows exactly what causes colorectal cancer, but a number of risk factors have been identified. These include:

  • Age. About 90% of people diagnosed with colon cancer are over age 50.
  • Genetics. Genetic syndromes cause 5-10% of all colon cancers.
  • Family history of colorectal cancer. About 20-25% of colorectal cancers occur among people who have a family (parent, sibling, or child) history of the disease.

Read more

Related Health Centers:

Breast Cancer, Cancer Introduction, Colorectal Cancer, Prostate Cancer

The material on this site is for informational purposes only and is not intended as medical advice. It should not be used to diagnose or treat any medical condition. Consult a licensed medical professional for the diagnosis and treatment of all medical conditions and before starting a new diet or exercise program. If you have a medical emergency, call 911 immediately.