GI Conditions

Colorectal Cancer

What is colorectal cancer?
Colorectal cancer is a cancer which can develop anywhere in the large intestine with the majority of colorectal cancers beginning as polyps inside the colon or rectum.

What causes colorectal cancer?
The exact cause of most colorectal cancers is unknown.  Colon cancer develops due to changes in the colon lining.  These changes may be inherited or develop as the result of mutations occurring during a person’s life, the causes of which are not fully understood. Common risk factors are family history of colorectal polyps or colorectal cancer, personal history of  ulcerative colitis or Crohn’s disease, high fat diet, obesity or smoking.   However, some patients may have none of these risk factors, thus screening all individuals over age 50 years (and African-Americans over age 45 years) is important.

What are the symptoms of colorectal cancer?
Getting screened regularly for colorectal cancer is extremely important because polyps and cancer don’t always show symptoms.  Once symptoms such as blood in the stool, change in bowel habits, abdominal pain and weight loss develop, advanced cancers may be present.

What are the tests used to diagnose colorectal cancer?
Your doctor will help determine which test is appropriate for you.  Test options include:

• Colonoscopy – The doctor uses a thin, flexible, lighted tube to check for polyps or cancer inside the rectum and the entire colon. During the test, the doctor can find and remove most polyps and some cancers.
• Flexible sigmoidoscopy – A short, thin, flexible, lighted tube is inserted the rectum to check for polyps or cancer in the bottom third of the colon and rectum.
• High-sensitivity stool test for blood – This test is performed at home by using a stick to obtain a small amount of stool.  The stool samples are returned to your doctor to be tested for occult blood.  However, stool tests may miss precancerous polyps and cancers and are therefore not a substitute for colonoscopy screening.

How do I know which screening test is right for me?
Your doctor will help determine which tests are right for you based on the benefits and potential risks associated with each screening option.

Are there limitations to colonoscopy?
Studies show that even in expert hands, under good conditions, colon polyps and even colon cancers are occasionally missed during colonoscopy.  A good clean-out of the colon and an experienced gastroenterologist endoscopist are essentials for an accurate examination. Colonoscopy is still the most accurate test and one in which pre-cancers can be removed and prevented from developing into cancers.