The exclusion criteria were a history of colorectal cancer, adenomas, or inflammatory bowel disease; life expectancy of <5 years; flexible
sigmoidoscopy or colonoscopy procedure within the previous 3 years, or were unable to provide informed consent.
Other options now recommended include computed tomographic colonography (CTC), fecal immunochemical tests with DNA (FITDNA), guaiac-based fecal occult blood testing (gFOBT), and
sigmoidoscopy plus FIT.
KEY WORDS: Sigmoid colon, Volvulus,
Sigmoidoscopy, Diagnosis, Treatment.
Flexible
sigmoidoscopy involves inserting a small malleable scope via the anus to examine the last third of the large intestine (colon) where most cancers originate.
Endoscopic screening can be done using flexible
sigmoidoscopy or colonoscopy.
According to Imperiale, the findings suggest that for women under 70,
sigmoidoscopy - which uses a long flexible tube equipped with a tiny video camera to see the interior of the colon -could be adequate as an initial colon cancer screening.
In addition, results from the Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening Trial showed that study participants in the flexible
sigmoidoscopy group had a 26% reduction m overall colorectal cancer mortality and a 50% reduction in mortality related to distal colorectal cancer, compared with the usual-care group.
Colonoscopy use increased steadily, whereas
sigmoidoscopy use declined during 1998-2005 (Shapiro et al.
Nick Phillips of Bowel Cancer Wales, who has campaigned for flexible
sigmoidoscopy - also known as flexi-sig - said: "This can reduce both the incidence rate of bowel cancer and fatalities - we shouldn't have to chase after these developments in screening.
A 16-year clinical trial on 170,000 people aged 55 to 64 found that those who underwent a one-off
sigmoidoscopy had a third lower risk of bowel cancer and nearly half the risk of dying as those who didn't.
In their recommendations on structural screening tests, the task force concluded that colonoscopy, flexible
sigmoidoscopy (with insertion to 40 cm or to the splenic flexure), double-contrast barium enema, and computed tomographic colonography (also called virtual colonoscopy) would all be acceptable for individuals at average risk.
The American Cancer Society recommends that at age 50, men and women have a fecal occult blood test annually; a flexible
sigmoidoscopy or barium enema every five years; and a colonoscopy every 10 years.
