Sigmoidoscopy Effective for Colon Cancer Screening

Studies have indicated that sigmoidoscopy, which is less invasive and better tolerated than other methods of colon cancer screening, may be just as effective at preventing colon cancer deaths as traditional colonoscopy.

Approximately15,000 American men and women were randomly picked to receive a flexible sigmoidoscopy screening on 2 separate occasions. Of those chosen, 21% were less likely to develop colon cancer than those who were not screened. Of this group, 26% were also not as likely to die from colon cancer because of early detection of pre-cancerous polyps. The study was reported in the New England Journal of Medicine.

Dr. Alfred Neugut, an oncologist and epidemiologist from New York, who wasn't part of the study team, explained that colonoscopy is a very uncomfortable procedure. He said the flexible sigmoidoscopy is a simpler one and is less invasive.  The procedure does not require anaesthesia and is known not to cause any pain. With colonoscopy, a thin flexible tube is inserted through the anus and guided to the intestines. With a small camera, it can see if there are tumors or growths which can then be taken out since a small cutting instrument is also attached to the apparatus. With sigmoidoscopy, the instrument is inserted up to the 1/3 of the colon where the polyps and tumors are most likely found. Sigmoidoscopy also does not need the rigorous preparation that a colonoscopy requires.

Another study headed by Dr. Robert Schoen of the University of Pittsburgh Medical Center showed how well sigmoidoscopy would work as a screening for colon cancer. Between the years 1993 and 2001, people between the ages of 55 to 75, were subjected to the test. The subjects were also examined 3 to 5 years after. Only those with doubtful results were sent for colonoscopy. After 12 years of follow up tests, 21% had fewer incidence of colon cancer and 26% had chances to die of the said disease. 243 people cases were diagnosed through sigmoidoscopy.

Co-leader Dr. Christine Berg, chief of early detection research at the National Cancer Institute, which sponsored the research, said that a larger number would have been detected had colonoscopy been used. He said the simpler screening test can be an option for those who do not want the unpleasant experience of colonoscopy preparation or if having anaesthesia will be a risk to the patient.

The US Preventive Services Task Force which is a government funded group has recommended three colon cancer screening tests and one of them is flexible sigmoidoscopy. The other two would be fecal occult blood test and colonoscopy. However, many Americans still do not get the screening even if they are of the age to have one. Many would say that they do not want the discomfort of colonoscopy preparation especially the taking of laxatives and the invasiveness of the method. The studies just made would certify that flexible sigmoidoscopy is good for initial testing and is a valid and sound alternative.