Research shows that the risk of cancer is low for 10 years if a high-quality colonoscopy does not detect cancer, so tests for this purpose are indicated every ten years.Colonoscopy screening prevents approximately two-thirds of deaths due to colorectal cancers on the left side of the colon, and is not associated with a significant reduction in deaths from right-sided disease.Colonoscopy reduces cancer rates by detecting some colon polyps and cancers on the left side of the colon early enough that they may be treated, and a smaller number on the right side; many of these left-sided growths would have been detected by a sigmoidoscopy procedure.Since polyps often take 10 to 15 years to transform into cancer in someone at average risk of colorectal cancer, guidelines recommend 10 years after a normal screening colonoscopy before the next colonoscopy. (This interval does not apply to people at high risk of colorectal cancer, or to those who experience symptoms of colorectal cancer. )Although widely touted in the US as the "gold standard" of colon cancer screening, colonoscopy has never been studied as a screening tool. Most of the potential benefits of colonoscopy have been extrapolated from randomized trials of the sigmoidoscopy. The CONFIRM trial, a randomized trial on colonoscopy vs. FIT is currently ongoing.
Gordon states, "At about $1,000 per procedure, theres clearly an economic incentive".The Hemoccult II FOBT (combined with follow-up colonoscopy if indicated by the test) is over 5 times as cost effective as other screening strategies, but is only about 85% as sensitive. Because of this relatively low sensitivity, US guidelines advocate the over 5 times more expensive procedures instead, because even the relatively small increase in lives saved and 5-fold cost increase is seen as worth choosing, given US living standards. History
In the 1960s, Dr. Niwa and Dr. Yamagata at Tokyo University developed the device. After 1968, Dr. William Wolff and Dr. Hiromi Shinya pioneered the development of the colonoscope. Their invention, in 1969 in Japan, was an advance over the barium enema and the flexible sigmoidoscope because it allowed for the visualization and removal of polyps from the entire large intestine. Wolff and Shinya advocated for their invention and published much of the early evidence needed to overcome skepticism about the devices safety and efficacy. Colonoscopy with CCD invention and market is led by Fuji film, Olympus and Hoya in Japan. In 1982, Dr. Lawrence Kaplan of Aspen Medical Group in St. Paul, MN reported a series of 100 consecutive colonoscopies and upper endoscopies performed in a free-standing clinic miles from the nearest hospital, demonstrating the safety and cost effectiveness of these outpatient procedures.