The American Cancer Society and the US Centers for Disease Control and Prevention recommend that men and women at average risk of developing colorectal cancer begin screening for colorectal cancer soon after turning 50, then continue getting screened at regular intervals.
Regular screening can find colon cancer early, when treatment is most effective and gives a chance of a longer life.
People considered to be at average risk of colorectal cancer are those with no family history and few, if any, other risk factors. (See Caymanian Compass, 22 March for risk factors.)
Tests and procedures used to screen for polyps and colorectal cancer can be divided into two broad groups: Tests that can find both colorectal polyps and cancer and tests that mainly find cancer. Some of these tests are invasive, while others are simple blood tests.
This week, we will focus on the tests that can find both cancer and polyps.
The American Cancer Society recommends choosing between the following options.
Double contrast barium enema (DCBE): This involves an X-ray examination of the large intestine (colon and rectum). To do this test the contrast material, a white liquid, is pumped into the colon through a thin tube inserted into the rectum. Air is then pumped in to cause the colon to expand, allowing good X-ray pictures to be taken. If an area does not look normal you will need to have a colonoscopy. The American Cancer Society recommends that this test be administered every five years.
Flexible sigmoidoscopy (flex-sig): A thin, flexible, lighted tube with a small camera attached (called a sigmoidoscope) is inserted in the anus and allows the doctor to examine the rectum and the part of the colon next to the rectum. Due to its size, the doctor is only able to see about half of the colon. If a small polyp is found your doctor may remove it with tools used through the scope. If a bigger polyp or colorectal cancer is found, a colonoscopy will be necessary to examine the rest of the colon. This test usually takes 10 to 20 minutes. The American Cancer Society and the Centers for Disease Control and Prevention recommend this test be administered every five years.
Colonoscopy: A colonoscope is a longer version of the flex-sig. It is used the same way but allows the doctor to see the entire colon. If a polyp is found growing, the doctor may remove it. Polyps can develop into cancer, thus, the removal of these polyps can prevent cancer altogether. If anything else looks abnormal, a biopsy might be done. To do this, a small piece of tissue is taken out through the colonoscope and sent to the lab to check for cancer cells. This test usually takes about half an hour and a sedative is given beforehand. It is recommended that this test be administered every 10 years.
Virtual colonoscopy: Virtual colonoscopy also known as CT colonography, is an exam used to detect changes or abnormalities in the large intestine and rectum. A small tube (catheter) will be inserted through the anus and into the rectum to fill your colon with air or carbon dioxide. During this exam, either an MRI or a CT scanner takes many pictures of the colon as it rotates around you while you lie on a table. Special computer programs then create both two dimensional x-ray pictures and a 3-D view of the inside of the colon and rectum, which allows the doctor to look for polyps or cancer. This test is an alternative to those where a tube or scope is put in the colon or rectum. It is strictly a diagnostic procedure, therefore, if any clinically significant polyps are found, they will have to be removed by conventional colonoscopy.
Prior to having a flex-sig, colonoscopy, virtual colonoscopy or barium enema some preparation is required. For best results, the colon must be clean and free of stool. The patient receives instructions on how to do this from their practitioner. It involves drinking a solution which flushes the colon clean or taking laxatives and enemas.
Any discomfort or embarrassment from colon cancer screening is temporary. Remember, detecting problems early could be lifesaving.
The Cayman Islands Cancer Society is dedicated to increasing the level of awareness of everyone on the various ways of preventing colorectal cancer through presentations. These are offered free of cost to companies and their employees, schools, clubs and church groups. To schedule a presentation call 949-7618.