The article Colonoscopy Still ‘Gold Standard’ For Preventing Colon Cancer, Johns Hopkins Expert Says mention that the colonoscopy is the gold standard in detecting colon cancer even though there are still other tests that help.
A colon cancer expert at Johns Hopkins says that a colonoscopy remains underused by Americans but remains the test of choice for preventing the number-two cancer killer overall. [...]
“People shouldn’t be afraid. The days of discomfort, doubt and danger often associated with a colonoscopy are long gone. And, most importantly, it saves lives,” adds Kalloo.
However, another article COLONOSCOPY: IS IT WORTH THE RISK? says otherwise.
So our desire to prevent it isn't surprising, especially when we are told that regular colonoscopies after age fifty make colorectal cancer "more than 90% curable — but only if you get tested in time." 
Actually, this is a lie! Screening colonoscopies do not prevent or materially reduce anyone's risk of colorectal cancer regardless of age. And if anything, they may actually increase your overall risk of cancer, and not just colorectal.
Also, another article Standard Colonoscopy mentions
Even though this test is highly sensitive, it still may not detect all small polyps, nonpolypoid lesions, or cancers.
So, is colonoscopy the gold standard in detecting colon cancer?