Contact Us

(707) 399-9200 

Frequently Asked Questions

Digestive Disease Center

Why should I be tested for colorectal cancer? 

​​Colorectal cancer (cancer of the colon and the rectum)
is the third leading cause of cancer deaths in the United States. This disease is also one of the most  preventable cancers because of effective testing (screening) options. Colorectal cancer screening can help find early signs of cancer in the colon and rectum.

How can I be tested for colorectal cancer?
The two most widely available and effective tests for reducing colorectal cancer deaths are the fecal occult blood test (FOBT) and flexible sigmoidoscopy. A FOBT is done with a stool sample collected at home, using a kit you may receive from the lab, or by mail.
A flexible sigmoidoscopy is an exam of the rectum and lower part of the colon using a thin flexible tube about as thick as a finger. A specially trained doctor or nurse will use this tube to look for polyps (non-cancerous growths) and small cancerous tumors.

What is the FOBT test like?

The fecal occult blood test (FOBT) screens for blood in the stool by placing a small sample of stool on a chemically treated card. This test is completed at home, then either mailed or brought into the lab. If blood is detected in the sample, a total colon evaluation (colonoscopy or barium enema) will be performed as follow-up. The FOBT is a very quick test with no known side effects.

What is the flexible sigmoidoscopy like?

Flexible sigmoidoscopy is a routine procedure that can be performed in a doctor’s office. It is done while you are fully awake. In flexible sigmoidoscopy, a specially trained doctor or nurse will gently insert a thin, flexible tube into your rectum and gradually move it through the lower part of your colon, while you are resting on your side. When this occurs, many people describe having a feeling similar to needing to go to the bathroom. Most people also experience some cramping or bloating during the brief exam. After the exam is over, these sensations usually go away quickly. The actual test takes only about 5 to 10 minutes.

You will be instructed to take several enemas or an oral bowel preparation two hours before the exam. This will clear your lower colon and rectum. After the exam, you should be able to return to your regular activities. You may want to plan for time to rest after the test is finished in case you are experiencing bloating or gas.

What about colonoscopy for colorectal cancer screening?

A colonoscopy test is like a flexible sigmoidoscopy, but it looks at the entire colon. Unlike a flexible sigmoidoscopy, you are sedated for a colonoscopy. Colonoscopy has more risks than sigmoidoscopy. These include bleeding, problems from sedation, and damage to the colon wall. Because of these risks, it is only recommended for screening high-risk patients.

Who should be screened for colorectal cancer, and when? 

All healthy adults 50 years of age and older should schedule their first colorectal cancer screening test. FOBT screening should be performed every 1-2 years. Flexible sigmoidoscopy or colonoscopy should be performed once every 10 years, unless advised by your doctor. The FOBT can also be used in combination with flexible sigmoidoscopy to screen for colorectal cancer between procedures. 

If you are at high risk for colorectal cancer, you need special screening and should ask your doctor about how often you should be tested. People with a personal or a strong family history of colorectal cancer are at a higher risk for the disease than others. Men and women are at equal risk for colorectal cancer. Be sure to talk with your doctor about when and how often to get tested if: 
·       You have ever had colorectal cancer; or

·       Your sister, brother, parent, or child has had colorectal cancer before the age of 55; or 

·       Two or more of your sisters, brothers, parents, or children have ever had colorectal cancer at any age.


​​You should also talk to your doctor or advice nurse if you are having persistent rectal bleeding, diarrhea, constipation, or stomach pain.

How do I schedule an appointment for colorectal cancer screening?


​If you are not experiencing any pain or bleeding from your rectum and you do not have a personal or family history of colorectal cancer, you should schedule your first FOBT or flexible sigmoidoscopy when you are 50 years old.


Your doctor can provide you with the testing kit for FOBT either at an appointment or by mail. When you have completed the test at home, you can either bring in the specimen, or mail it back to the lab.


You will need a referral from your doctor for either a flexible sigmoidoscopy or colonoscopy. When you schedule your appointment for either of these procedures, you may find that your appointment may be scheduled further away than usual. These can be popular appointments because the flexible sigmoidoscopy is a routine screening test for all of our members 50 years old and older. But if you are experiencing pain or bleeding from your rectum, tell your doctor or nurse so that your appointment can be scheduled in accordance with your special needs.


How do I prepare for a colorectal cancer screening?


There is minimal preparation for the FOBT test. Depending on your medical history, you may need to change your diet before the exam. There are no known side effects from this procedure. You can return to work immediately.


Preparing for a flexible sigmoidoscopy requires clearing your rectum and lower colon of stool so that the test will be accurate and complete.


This involves taking enemas or an oral bowel preparation and possibly changing your diet just before the test. When you schedule your appointment, you will receive more specific instructions.


Preparing for a colonoscopy involves taking a stronger enema or bowel preparation so that the entire colon will be clear for the exam. You will be sedated so that you are more comfortable and relaxed during the procedure. You may experience some bloating and discomfort. You will need to arrange for a ride home after the procedure.


What else can I do to reduce my risk of colorectal cancer?


In addition to asking your doctor or nurse about a screening test for colorectal cancer that is right for you, try to:

·       Choose foods low in fat and high in soluble fiber. This may help to reduce your risk of colorectal cancer by regularly moving waste out of your bowels. To get lots of fiber, eat five servings of fruits and vegetables every day. You can also get fiber from bran cereals, whole grain and whole wheat breads, cooked beans, peas, and popcorn.

·       Quit smoking. If you smoke, we can help you quit. Ask your doctor for resources.

·       Get lots of physical activity (like walking or yard work). Physical activity can also help improve your overall health.  


***This information is not intended to diagnose health problems or to take the place of medical advice or care you receive from your physician or other health care professional. If you have persistent health problems, or if you have additional questions, please consult with your doctor.***