Can all types of colon cancer be detected by ct scan or colonoscopy is necessary for detection?

Colon screening : To see inside the colon well , it needs to be cleaned very well So a colonoscopy or a CT scan can be limited in its ability to detect cancer. A recent study, this month, found that special CT scans, designed to screen for colon cancer, were found to be as good (actually 1% better) as a colonoscopy to detect cancer. Regular CT scans can find colon cancer but not as good as a colonoscopy.